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Gun Glossary - Letter T
Index of Firearm & Gun Terminology

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Letter - T Page Updated: 06 March 2003

T-65: Original designation for the U.S. Army's 7.62 x 51mm NATO cartridge.  The T-65 was developed by Winchester in the early 1950's and was introduced commercially as the venerable caliber .308 Winchester rifle cartridge.  Also know as .308 Win.

TACTICAL: Relating to or using tactics, which could include established principles and procedures for combat effective fire and maneuver. Of, relating to, used in, or involving military or naval operations that are smaller, closer to base, and of less long-term significance than strategic operations. Carried out in support of military or naval operations: tactical bombing. Characterized by adroitness, ingenuity, or skill.

TAKE DOWN: A gun which can be easily taken apart into sections for carrying or shipping.

TAKE DOWN PINS: Removable or sliding pins that are slide or removed from a gun so it can be taken apart.  The most common "take down pin" gun is America's rifle the AR-15 and the American military version the M16.

TANG: An extension of the receiver into the stock.

TANK: Military Armored vehicle that has caterpillar traction and is armed with machine guns, cannon, rockets, or flamethrowers.  It was developed by the British and first used (Sept. 1916) in World War I.  In World War II tanks and tank tactics were greatly improved. The German army, using large numbers of tanks, overran Poland in less than a month.  In mass tank battles on the plains of Europe and North Africa the tide often swung toward the side with the best tanks. Since World War II the basic features of tanks and tank tactics have remained unchanged, although there have been numerous technological refinements. Tanks are vulnerable to recoilless weapons and various antitank missiles, but they remain indispensable, because of their mobility and versatile weaponry, wherever the terrain is suitable to their operation.

TARGET: A mark or object to shoot at.  Something fired at with a gun.  Many types of targets exist for shooting competition and recreation.  Target types include Paper with a traditional "bulls eye" or concentric rings and circles, human torso type silhouette targets are typically used by law enforcement, metal plates of varying sizes and shapes to include game animal forms and clay or frangible items used for skeet or trap shooting. Targets can be made of just about anything, the most common being paper and cardboard.  


Caution needs to be taken when emplacing and positioning targets.  Target must be positioned to ensure a safe field of fire and to prevent injury or damage to property. Most modern and some classic ammunition can propel bullets and projectiles fired from firearms great distances. The area behind the firing line needs to examined and evaluated. 

Additional precautions need to be taken when shooting hard, metallic or steel targets to avoid injury of the shooter or by standers.  The standard for safe distance depends on the material and construction of the target. 7 to 10 meters is standard in many form of competition where hard targets are engaged. 

Ammunition which is designed to be used for shooting (paper or steel) targets.  Since the design priority is accuracy rather than terminal effect in soft tissue or stopping power, target ammunition is not loaded "hot".  Target ammo does not include "defensive features" such frangibility or a hollow point.  It is usually inexpensive.

TARGET, CLAY:  A circular, domed frangible disc used as an aerial target for shotgun shooting games. Originally formed out of clay, modern targets are a combination of pitch and limestone. Dimensions and weights are regulated by trap and skeet shooting associations. They are often called "clay pigeons."

TARGET RIFLE: Rifle used for specified types of target shooting. Target rifles fall into three general groups: offhand or Schuetzen; Creedmoor or long range; and bench rest.  These three group classifications originated in the last century but are still descriptive today, the principle being that the offhand rifle is today called the Free or International Rifle.  We generally call the Long Range Rifle, long range rifle.  Since several years ago, the latter type was also referred to as the Wimbledon rifle.  Bench rest target rifles are still called by that name.

TEFLON: Trade name for a synthetic sometimes used to coat hard bullets to protect the rifling. Other synthetics, nylon for instance, have also been used as bullet coatings.  None of these soft coatings has any effect on lethality.

TELESCOPIC SIGHT:  A small arms sight that employs optics to provide a magnified view of the target. A telescopic sight does not make a small arm more accurate, but rather helps the shooter to distinguish a distant target from its background. Also refereed to as a Scope.

TERMINAL BALLISTICS:  The branch of ballistic science which deals with the effects of projectiles at or on the  target.  Terminal ballistic measurements include impact energy, penetration depth, weight retention, wound channel and bullet expansion.  Terminal Ballistics is concerned with the phenomena occurring at the termination of the projectile's flight; such termination may result from impact on a solid target or the explosion of the projectile.

For additional information on Ballistics go to: Gun Glossary Letter B - Click Here.

For detailed information on Terminal Ballistics see the article below.

Terminal Ballistics Primer
Written by John Schaefer - a.k.a. Father Frog
Copyright © 1998-2003
- Father Frog's Home Page & John Schaefer - All Rights Reserved.

"This article was originally published on Fr. Frog's Home Page & is used here with his express 
written permission."   Fr. Frogs Home Page is at Web URL:

Terminal Ballistics

Terminal ballistics is the science of what happens when the bullet strikes the target (and thus the mechanism of incapacitation). For a very long time this field was based on myths, misunderstandings, and in many cases outright misstatements. It wasn't until accurate tissue simulates and modern high speed x-ray photography started to be utilized that much of what happens began to be understood more fully. 

Even today there is still a lot of terminal "bull-istics" being put forth by self-styled experts based on so-called "street data," pet theories of the proponent, and some cases even manufacturer's incentives. However, those who have taken the time to research the subject and who understand the medical principles involved have learned to separate the bull from the bullets.

Definition of Terms

Armor Piercing - A bullet constructed of hardened material or carrying a hardened core specifically designed to penetrate bullet resistant, or armor-plated targets such as tanks, trucks, and other vehicles. Depending on the definition used for "armored" any small arms ammunition could be considered armor piercing. As an example, a target designed to resist pistol ammunition can be penetrated by rifle ammunition, or a target designed to resist rifle fire ammunition can be penetrated by a light cannon.

Fragmentation - The disruption of the bullet into many pieces caused by the forces of impact on the bullet.

Full Jacketed - A bullet designed with the soft core of the bullet completely encased in a metal jacket to prevent expansion of the bullet upon impact. Fully jacketed bullets generally give the deepest penetration of any bullet design, all else being equal.

Geneva Convention) - A set of international agreements to provide for "civilized" behavior between nations at war. It is most frequent referenced for it's banning of the use of expanding bullets in small arms ammunition by warring parties--although the ban actually came about from the Hague accords. (The hoplophobic press also latches on to it whenever those "evil" dum-dum, cop-killer, flesh shredding, crime causing bullets are mentioned by the gun grabbing liberals.) In actuality this "ban" is very misleading for while expanding projectiles are proscribed, the use of mines, explosives devices, and flame weapons which indiscriminately shred, maim, and disfigure their victims are not. In fact, an expanding bullet is simply an attempt to make a small diameter projectile as effective as a large diameter non-expanding one. A wound made by a large non-expanding bullet is virtually indistinguishable from that made by a small bullet which expanded to the same size.

Hollow Point - A bullet (usually of jacketed construction) designed with the soft core of the bullet exposed by means of a cavity in its nose to facilitate expansion upon impact. Actual expansion can be altered by intervening material or by the bullet's construction.

Permanent Cavity - The permanent "hole" left in the target by the bullet's passage. It is caused by the crushing and cutting effect of the bullet. Depending on the bullet's design it can be quite large in diameter or hardly noticeable. Pointed or round nose non-expanding, non-tumbling bullets make the smallest holes.

Penetration Depth - The final depth of the projectile's penetration at the end of the permanent cavity

Semi-wadcutter - A bullet designed with a sharp bore diameter shoulder the enhances its cutting action without requiring expansion.

Soft Point - A jacketed bullet designed with the soft core of the bullet exposed at its nose to facilitate expansion upon impact. Softpoint bullets tend to give slower expansion and deeper penetration than hollow points all else being equal. Actual expansion can be altered by intervening material or by the bullet's construction.

Temporary Cavity - The boundary of the temporary displacement of tissue by the hydrostatic effect (fluid pressure) of the bullets passage.

Incapacitation - (Hey! STOP that, right now!)

The subject of incapacitation is one of vital interest to anyone who depends upon a firearm to either protect their life from an assailant or who needs to stop a dangerous animal. What is needed in both cases (and even in the case of a non-dangerous game animal) is to turn off--S T O P--whatever the target is attempting to do, whether it is trying to kill you, someone else, or simply trying to run away. Whether or not the target eventually dies of the wound(s) is of only academic interest at the moment of the shot is fired. You want (need) instant (or as near to instant as you can get) results!

For a long time many individuals believed that the mechanism of incapacitation was either energy transfer (how many foot-pounds of bullet energy was dumped into the target) or the size of the temporary cavity caused by the "shockwave" of the bullet's passage, or as some writers would have you to believe, the brand of ammo (usually the brand that they were getting free).

However, modern medical science has shown us that the mechanism of incapacitation, while still not completely understood is based on two components. First is the permanent tissue and nerve destruction caused by the cutting and crushing action of the bullet's passage. In other words, making the biggest diameter and deepest hole that you can. The other component is not as easily as quantifiable and is the physical and emotional state of the target. A target pumped up on adrenaline or affected by narcotic or psychotic drugs can be extremely resistant to bullet caused trauma while a target full of fear and self doubt may "cease and desist" from a very minor wound. Since we cannot control the target's physical or mental state we have to just worry about doing all damage that we can TO the target.

Some will state that bullet placement is also a component. While in actuality it does play a part in the final results it is not a component of bullet performance. A well placed hit that causes inadequate damage may be of infinitely less use than one that causes massive and deep damage in a less well placed hit. (Although, ideally what you want is a well placed hit that cause massive damage.)

Let's look at some of the theories, past and present.

Energy Transfer School - In this school of thought the more foot pounds of kinetic energy a bullet "dumps" (looses) in its journey through the target the more effective it should be in incapacitating the target. The measurements were derived by measuring the bullet's velocity at impact and also its exit velocity (if any) and then comparing the kinetic energy of the projectile at those two velocities. The difference was considered the energy transferred to the target. Under this theory a .22 Long Rifle bullet which did not exit the target could be more "effective" than let's say a .357 that blew right through the target. (While this is an extreme example you get the point.) What the bullet did TO the target while traversing it was not examined. This school of thought favored light-weight high-velocity bullets which possessed high kinetic energy and which usually did not exit their target.

Temporary Cavity School - In this school of thought the larger the temporary cavity made by the bullets passage the more effective it should be. The measurement of the temporary cavity was derived by measuring high speed x-ray photographs of the temporary cavity displaced by the bullet on the theory that the farther tissue was displaced the greater the nerve trauma. In general the faster the bullet is traveling the greater the temporary cavity, all else being equal.

Several thing have proved wrong with this theory. First of all, as any surgeon knows, muscle and bowel tissue is very elastic. During surgery such tissue can be moved substantial distances without any harm to the person. Second, most temporary cavities are quite shallow (although bullet design plays a role here) and thus do not effect much in the way of vital organs. Third, the temporary cavity is of very short duration and unless the limits of elasticity are reached (which take velocities in the 2700 f/s and higher range) no permanent damage or injury results. The exception to this is inelastic tissue such as organs like the liver, kidneys, and spleen--but counting on hitting one of those organs is a risky business.

There is, however, an instance where temporary cavity size may aid in the actual wounding and incapacitating process. That instance is when the bullet fragments during the creation of the temporary cavity. This can sometimes cause the tissue to suffer somewhat more damage than by just the bullets passage alone as the tissue can be cut or damaged during its stretched or stressed state by the bullet fragments and thus create a somewhat larger permanent cavity. If the wound is deep enough this can increase the incapacitation effect.

The school also tends to favor high velocity although bullet construction/performance is also considered.

Big Hole School - In this school of thought, and the medically correct one according to recent research, the more permanent damage that is done to the target (and incidentally the more rapidly the target bleeds out) the more effective the bullet and more likely incapacitation. The more tissue cut, crushed, and/or destroyed by the bullet's passage the better, as more real system trauma results. In addition, in order to be effective at all target angles the bullet must penetrate sufficiently to reach vital organs in the target no matter from what direction the bullet impacts. Most authorities agree that for anti-personnel use a minimum penetration in calibrated ballistic gelatin of about 11-12" (with 15" being considered ideal) is needed. This is necessary to achieve reliable performance under all conditions against a human target. It should be noted that minimum depth for major blood vessels in a human is about 15cm ( 6"). With bullets used for hunting the general consensus is the deeper the better. In both cases this has to be coupled with the ability to create the largest diameter permanent hole possible. Most authority seem to agree that the hole needs to be at least .5" or greater in diameter and as deep as possible. A problem arises here in that as a bullet expands it tends to penetrate less, so expansion and penetration have to be carefully balanced by bullet weight and bullet construction. This bullet design problem is exacerbated by the fact that if a target is covered by some material such as cloth, glass, metal, etc. the expansion--and hence the penetration of the bullet--can alter dramatically.

This school tends to favor medium to heavy weight bullets at moderate velocity, with a general preference to bullets of .40 caliber and greater.

One word about depth of penetration. Some people in law enforcement hold that too much penetration with ammunition used for self defense is a bad thing. They warn that a bullet that passes through a target may hit someone else resulting in all kinds of law suits. However, considering that it is estimated that 80 percent of the shots fired in law enforcement situations fail to even hit the target. (Gunsite grads excepted!) I wouldn't worry too much if your ammo is penetrative. Better too much than not enough when the chips are down.

Anatomy of a Bullet Wound

One of the tools used to compare the effects of ammunition is the "wound profile." Wound profiles are simply dimensioned photographs or carefully prepared scale drawings of test firings in calibrated ballistic gelatin. The wound profiles below are some typical examples of what a bullet does on impact.

Properly prepared and calibrated ballistic gelatin gives performance and penetration results within about 2 percent of results obtained in actual tissue. "Properly prepared" means that the gelatin is a 10 percent mixture of ballistic gelatin (Kind and Knox Type 250) prepared water heated to no more than104° F (40° C) and then stored and shot at a stabilized 39° F (4° C).

This particular profile is that of an early .45ACP 185gr. Silvertip Winchester @ 940 f/s. This is a classic non-fragmenting expanding bullet wound profile. The narrow portion at the start of the permanent cavity is called the "neck" and its length is a function of the bullet's design. This particular load is a little short on penetration at 25cm (9.8") with an expansion of .85". As a comparison the Hornady +P 230gr XTP at 880 f/s gave 15.6" penetration and .72" expansion, the Hornady 200gr XTP at 850 f/s gave 18.5" and .54", the Winchester 230gr Black Talon at 858 f/s gave 13.5" and .73", and the Remington 185gr at 1020 f/s gave 10.5" and .83". Interestingly, Winchester must have got the word because a later lot of this ammunition gave 882 f/s and 11" of penetration and .74" expansion. For comparison the GI M1911 Ball ammo (230gr at 869 f/s) produced a penetration of 26".
This is the wound profile of the 7.62x39 PS Steel Core AK-47 round at 2340 f/s. Great penetration but otherwise not very impressive, eh? The permanent cavity is flat in cross-section. I removed two sections so the image would fit on the page better. At around 60cm the bullet yawed downward and wound up base first as shown.


This profile is of the Winchester .30-30 170gr Silvertip at 2020 f/s. This is typical of medium velocity, expanding rifle bullets.

This profile is of the Winchester .30-06 150gr Softpoint at 2923 f/s. Note the larger permanent cavity than the .30-30 but almost identical penetration. Not something you want to get shot with.

What to do, what to do...

While the energy dump school has been disproved there is still a minor battle going on between the temporary cavity and big hole schools, and perhaps the real answer lie somewhere between the two. There are many failures of both the high performance/high velocity temporary cavity loads (especially the lighter bullet weight loadings) and also the big bore/big hole loads. While general experience seems to favor the big hole loads, nothing is certain. A lot still depends on the condition of the target.

One famous case of small and fast failure (temporary cavity loads) was widely distributed in law enforcement training circles. A perp (Oops, excuse me--alleged perp.) received an incredible number of 9mm expanding bullets (somewhere around 36--all over his body including the chest and face) yet was not seriously inconvenienced for several minutes. Another similar case was the infamous FBI Dade County shoot out wherein one of the aggressively behaving antisocial misfits was hit solidly with a "high performance" 9mm 115gr JHP. Though the wound would have eventually proved fatal, it failed to penetrate deep enough. He was able to continue fighting and killed several agents with a rifle before being taken out of the fight with a more powerful and destructive load.

As to "big hole" failures, here in the People's Republic of NJ there was an incident awhile back that shook a lot of folks. A drugged up goblin was shot through the back door and seat of a van he was driving with a 12ga slug. He exited the van with an inch-and-a half hole blown clear through his chest. (Yes, Virginia, daylight was visible!) He ran about 25 yards firing his pistol at his pursuers until he collapsed. (And you thought you were well armed with your 9mm / .357 / 10mm / .45, eh?) Check the wound profiles above for the 12ga slug and compare it with a pistol bullet profile. Then ask yourself if you will ever feel well armed ever again. Under those circumstances a tactical nuke might have been needed to provide the needed incapacitation.

In the hunting area I'm sure that you have heard of accounts of Cape Buffalo receiving well placed hits of tremendous size and power (500 grains at 2000-2400 f/s) and who yet turned on their antagonist with malice afore thought and lethal intent even though the should have, by all rights, been dead on the spot.

Always, keep this medical fact in mind:

Bullet hits to the torso cannot be counted upon to cause a person (or for that matter a game animal) to immediately cease his actions. Even a total loss of blood flow to the brain can still allow 10 seconds of purposeful action --more than enough time to empty a magazine into you or to stomp you to death.

As for me, even though there are no guarantees, I want to stack the deck in my favor as much as possible. I want to reliably cause the most damage possible with every shot. Since bullet expansion can't always be counted on due to intervening material and Hornady or Winchester don't offer tactical nuclear bullets, I don't like to count on a small bullet hopefully expanding to a bigger diameter. I like to stay with big at the start. Should I ever be lucky to go after dangerous big game I'll use all the gun I can handle. For personal defense I carry a .45 with 200-230 grain expanding bullets of proven design and penetration, but wouldn't feel too under gunned with a stout .40/10mm.

...and then there is always the Mozambique drill. But that's another topic

I hope that the forgoing has provided some food for thought and I'm sure that I will be hearing from some of you. You can email your comments and ideas to me at [email protected].

Special Thanks to Mr. John Schaefer - a.k.a Father Frog

"This article was originally published on Fr. Frog's Home Page & is used here with his express 
written permission."   Fr. Frogs Home Page is at Web URL:

Terminal Ballistics - Copyright © 2002 - John Schaefer - All Rights Reserved.

advanced terminal ballistics
Advanced Terminal Ballistics
Written by John Schaefer - a.k.a. Father Frog
Copyright © 2002 - Father Frog's Home Page & John Schaefer - All Rights Reserved.

"This article was originally published on Fr. Frog's Home Page & is used here with his express 
written permission."   Fr. Frogs Home Page is at Web URL:

The Power of the Rifle - Some thoughts on what makes one cartridge "better" than another.

Ah ha! Now we come to a controversial topic. It probably should really be under the heading of "Terminal Ballistics," but for now we'll discuss it separately. The topic is "power" and just what "power" increments are meaningful. As with the pistol, the way that a rifle bullet works is by creating as much permanent damage as is possible and what does this is the destruction of tissue by the bullet's passage.

The trick is to determine the damage level you need for your intended target and to then choose your weapon. It stands to reason the bigger and/or more dangerous your target the more damage you need/want to do. As a bonus, with rifles we don't have to worry much about a "power ceiling" as we do with pistols because controllability is not a real issue here.

Unfortunately, there has never been the level of study put into the effectiveness of rifle ammunition that has gone into pistol ammunition so a lot of myths still exist for the rifle shooter. Let's see what we can discover together.


If one is to believe the ammunition manufacturers and the so-called gun rag "experts" all one needs to do is to drive a given bullet faster and faster to get more "power." If one looks at the kinetic energy figures one simply needs to drive one's bullet to the next increment up in KE and you are ready for bigger/more dangerous game. According to them, "out there where the game is big, instead of your puny little .308 what YOU need is the new.300 Remingchester Soooper Magnum" and you are all set. To paraphrase the ancient masters, "Hog wash!" It is true that at the higher impact velocities of rifle ammunition (2300-2700+ fps), that the vaunted hydrostatic effect comes into play, but not at the level one would expect from reading the magazine hype.

One big disadvantage in increasing bullet velocity is that bullets are designed to expand properly over a fairly narrow range of velocities. If driven too fast they "explode" on impact giving a shallow wound channel or if not fast enough they fail to expand and just punch a small hole. A superficial wound will most likely, as it will with a human antagonist hit with a weak pistol shot, simply make what you shot more aggressive or allow it to escape.

Even the ammunition manufacturers admit under close questioning and a couple of sips of their favorite spirits that the KE figures in their ballistics tables are there to impress the uninitiated and sell ammo (just like the pistol data.) . And impress them it can because KE is a factor of the square of the velocity, and as we all know, velocity sells now days--in spite of what we presented on the external ballistics link. Look at the table below. If we are to believe it, all we have to do is buy the latest big powder bottle and we are in business

Velocity with
150 Grain Bullet
Kinetic Energy
Measured in FPE
2700 2430
2900 2800
3100 3200
3300 3630
3500 4080

Let's see now. A 150gr .30 caliber bullet at 2700 ± is generally considered suitable for game up to about 800 pounds by most authorities. The same bullet at 3500 out of the 300 Weatherby develops over 4000 ft lbs (which is fairly close to that of the .458 Winchester with a 500gr bullet which at 2000 fps which produces about 4440 ft lbs.) Which do you want to have in your hands when that Cape Buffalo gets an attitude? To get even more absurd, theoretically one could drive a 55gr .22 caliber bullet to slightly over 5100 fps and develop 3200 ft lbs of energy which some would have you believe makes it the equivalent of the .35 Wheelan with a 250gr bullet at 2400. Assuming you were sober which one would you want to use against an irate lion at 25 yards? Obviously kinetic energy isn't what we are looking for to quantify "more powerful."

It must be noted that kinetic energy does come into play with high velocity hard "penetrator" projectiles such as the "dart" rounds used in tank canon. There, the kinetic energy is used to literally burn through the target. I'll leave it to you to work out the KE of the M829 APFSDS-T (Armor Piercing Fin Stabilized Discarding Sabot-Tracer) 120mm round. It throws a 9.41 pound (that's 65,870 grains), 1.06" diameter, 31" long, depleted uranium dart at 5480 fps from the 120mm M256 smooth-bore tank canon on the M1A1 and M1A2 tanks. You can think of it as a really big bore Remington "Accelerator" round. For those of you who left your calculators back at the office, see the foot note at the very bottom of this page for the answer, along with a picture of a "dart."

However, KE might, however, be able to serve as an index of effectiveness at different ranges when comparing the same bullet weight and diameter at different velocities.

We have seen on the external ballistics page that velocity doesn't have a tremendous effect on trajectory until the DV exceeds 200 fps and even then the effect is really only noticeable at extreme range. It appears that the main effect of a velocity increase is to lengthen the range at which a given level of performance occurs. Just for grins lets assume that the given level of performance is the delivery of 1300 ft lbs of energy. (Yes, yes, I know... let's just assume and we'll also assume that we have a magic bullet that performs properly over a wide velocity range.)

I case you are wondering, I came up with this figure from Jeff Cooper's description of what the .308 Scout rifle was supposed to do--the taking of a target of up to 400kg (880 pounds), and his belief that 300 yards is the maximum range that one should attempt shots at game animals. (I have to agree with him because the average shooter can barely identify a target at 300 yards let alone hit it from field positions and in my experience an awful lot of folks can't consistently hit targets at 100.)

If we take 300 yards as the maximum "reasonable" range and assume the 150gr bullet as "standard" we come up with about 1300 ft lbs at 300 yards out of a 19" Scout so we'll use that as a standard of comparison. We'll launch a 150gr Hornady flat base from a.308 Scout, a .30-06, and a .300 Win Mag and look at the energy figures.

in Yards
Remaining Kinetic Energy -
Also expressed as Remaining Energy
MV 2700 3000 3300
0 2430 3000 3630
100 2000 2480 3030
200 1630 2040 2510
300 1330 1660 2060
400 1060 1350 1680
500 850 1087 1360
600 680 870 1100

MV = Muzzle Velocity in FPS - Feet Per Second

It would appear, if our assumption is correct, that all increasing MV by 300 fps does is to extend the "equivalent effective range" by about 100 yards. Since 300 yards is about the most anyone should attempt a shot at the whole thing kind of pales into insignificance. So the 300 Win Mag will do the same thing at 500 yards that the .308 will do at 300--Big deal! The target has to be hit first and I can count on the fingers of one hand the folks I know who can consistently hit with their first shot at 500 yards let alone those who know where their rifle shoots at that range. Besides you are burning 20-30 grains more powder just to get some meaningless increase.

Too many duffers believe the hype about the "magnums" and think that "more cartridge" will compensate for lack of marksmanship. In addition, all that powder going off causes faster erosion of the barrel's throat--not that many armchair hunters practice a lot with their rifles--and the increase in muzzle blast causes their already poor marksmanship to grow even worse. For the rare hunter or long range specialist who can make use of the slightly improved long range trajectory and power available from the big powder bottle rounds they may be of use. But for the "masses" I don't think so.

Ok, so we now know that upping velocity basically just extends the range at which a given level of performance occurs. The rest of the world needs something else to get more power.

Bullet Weight?

If caliber remains the same, an increase in bullet weight increases what is know as sectional density which is basically the ratio of weight to impact area. (It also produces lower velocities in the same cartridge.) The main effect of bullet weight is to increase penetration (all else being equal) although there can be a slight increase in the expanded bullet's diameter (assuming it expands) since there is more material to work with. This can make it a more effective bullet assuming bullet construction is up to the task. 

While penetration is to be greatly desired it is not the only thing we want. If all we want is deep penetration we can just use fully jacketed or bullets with a hardened steel penetrator core and we'll be able to punch clear through most things. However, once again I don't think you would be too happy about facing an irate moose or a cape buffalo with an attitude, up close and personal with a .308 loaded with M62 AP ammo. However on larger thin skinned game (within reason) going to a heavier bullet in a given cartridge will give you some more penetration.

Below is a table of the sectional density for some common bullets weights and calibers. Note that as the caliber is increased the "standard" bullets become proportionally heavier.


Bullet Weight
in Grains


.264 140 Grains .286 SD
.264 160 Grains .327 SD
.30 150 Grains .226 SD
.30 165 Grains .253 SD
.30 180 Grains .271 SD
.30 200 Grains .301 SD
.30 220 Grains .343 SD
.338 225 Grains .281 SD
.338 250 Grains .313 SD
.35 200 Grains .223 SD
.35 250 Grains .279 SD
.375 270 Grains .274 SD
.375 300 Grains .305 SD
.45 400 Grains .272 SD
.45 500 Grains .341 SD

Note the high sectional density for the 160 grain caliber .264 bullet. This is one reason why the 6.5 x 54 mm Mannlicher and the 6.5 x 55 Swedish cartridge was so effective on big game. It drove deep and expanded well. The other effect of increasing bullet weight is to help increase the ballistic coefficient of the bullet. It the bullet shape stays constant increasing the weight can yield a slight trajectory effect at long ranges. We'll use the Hornady .30 caliber flat base bullets bullets as an example. (Data from Hornady.)

Bullet Weight Ballistic Coefficient (C1)
130 Grains .299  BC
150 Grains .358  BC
168 Grains .400  BC
180 Grains .431  BC

However, remember that we have shown on the external ballistics page that a 15% change in BC at the same velocity has a negligible effect at reasonable ranges. We also saw on the external ballistics page a negligible change in useable trajectory with different bullet weights in the same cartridge if zeroed at the same range. It therefore appears that going to a heavier bullet in a given cartridge merely gives you some extra penetration (assuming proper and consistent bullet expansion).

More Bullet Weight and More Powder

Lets look at what we could do by using a bigger cartridge case with the same bullet diameter and burn more powder to launch a heavier bullet. All data based upon a 225 yd zero range with a 1.5" LOS. C1 ballistic coefficients are respectively .358, .431, and .485.


.308 Scout / 150 Grain

.30-06 / 180 Grain

.300 Win Mag / 200 Grain


Velocity KE Trajectory Velocity KE Trajectory Velocity KE Trajectory
0 2700 2430 -1.5 2750 3020 -1.5 2800 3481 -1.5
100 2540 2000 2.9 2540 2580 2.6 2610 3030 2.4
200 2220 1640 1.4 2340 2190 1.3 2430 2630 1.2
300 2000 1330 -7.2 2150 1850 -6.4 2260 2270 -5.9
400 1790 1070 -24 1970 1560 -21 2090 1950 -20
500 1600 855 -53 1800 1300 -46 1935 1660 -42
600 1430 680 -94 1640 1077 -80 1784 1414 -73

Caliber & Bullet Weight Table Key

Range = Distance in Yards
Velocity = Speed in Feet Per Second (fps)
KE = Kinetic Energy
Measured in Foot Pounds of Energy (FPE)
Also expressed as Remaining Energy in (FPE)
Trajectory = Distance above or below the Zero or Line of sight
FPE = Foot Pounds of Energy - The force exerted on the target 
Grain = Weight of the Bullet or Projectile

Here we might be able to make an excuse for a bigger case in the same caliber. Raising the bullet weight and keeping velocity about the same or greater allows us to drive more mass deeper and in those cases of large thin-skinned game may give us the additional penetration and "umpf!" we are looking for when going after BIG thin skinned game. In addition, note that with the same zero range the trajectories are all very close until one gets out past 300 yards. Unfortunately, you will still generate a small wound channel and while it might suffice for docile targets we need to be able to cause a more certain reaction on targets that might decide to cop an attitude and attempt to ruin our big day in the field.

Bullet Caliber

If you want a bigger hole, start with a bigger hole maker. As with the pistol, increasing the bullet diameter serves to increase the diameter of the permanent wound channel, which in and of itself is a "good thing," and it also, as a matter of course, increases bullet weight which helps to insure penetration.

Since it is apparent from previous investigations that for the most part simply jacking up the velocity does not make a particular cartridge more suitable for larger or more dangerous game, we may want to keep in mind that if we really need more power we really need to increase the bullet weight and also the bullet's diameter. This gives us more mass which is constant and a bigger permanent hole rather than velocity which is not constant. If you noticed in the sectional density table the "standard" bullets get proportionally heavier and heavier and for the most part have greater sectional density as caliber increases.

Notes from the field indicate that just as with the pistol, a bigger bullet has a greater effect on its target in the vast majority of cases. Deer usually fall faster when hit with a .35 than a .30, etc. given the same hit.

At this point I am sure that someone is asking, "How great an increase in caliber is needed to make a statistical difference?" That's a good question and as of yet I have not discovered an authoritative answer. I tend to think that a 25% to 50% increase in impact area is needed to be noticeably more effective but that theory is open for rebuttal. However, if one accepts that that .40 pistols are supposed to be noticeably more effective than the 9mms, one can look at the table below and see that a .40 cal has about 25% more area than a 9mm (.358). Same thing with the .30 caliber rifles and the .35 caliber rifles so perhaps there is something to this idea. One African hunter stated, when asked why he used a .600 Nitro double rifle, "Because they don't make a 700!" Nothing like a bigger hole!


 Impact Area (inČ)  

.224 .039
.243 .046
.257 .052
.270 .057
.284 .063
.308 .075
.338 .090
.358 .100
.375 .110
.400 .126
.458 .165
.500 .196

An interesting inference can be drawn from the hunting regulations in African countries visited by hunters. They base their regulations not just on KE but also on bullet diameter. The following are taken from the regulations in place in Rhodesia. (Oops! I mean The People's Democratic Republic of Zimbabwe.)

Part A - Thick skinned, dangerous game [Buff, elephant, hippo] requires a 9.3mm bullet (.362") or greater diameter bullet with not less than 5.3 kilojoules (3,909 ft-lbs) muzzle energy; [Yes, I've noticed. Only a fool hunts buff with a ".375." Maybe they are trying to kill off the Yankee tourists but at least they realize you need some kind of a "real" gun for the bad boys!]

Part B - Thin skinned, dangerous and heavy game [eland, giraffe, lion] requires not less than 7mm (.275") diameter bullet with not less than 4.3 KJ (3,172 ft-lbs) muzzle energy;

Part C - General big game [up to wildebeest and zebra, say 600-800 lbs] requires not less than 7mm (.275") bullet diameter with not less than 3.0 KJ (2,213 ft-lbs) muzzle energy;

Part D - Light big game requires a bullet at least 5.6 mm (.220") and 850 Joules (627 ft-lbs) muzzle energy.

The inch/metric equivalents are theirs, using the English System of measuring bores.

Closing Thoughts

One thing not touched upon in this discussion has been the effect of bullet construction. While this topic could take up several pages for discussion I think that it is safe to simply keep in mind that more weight or greater diameter will be useless if the bullet is not up to the intended task. A bullet that is too soft will open up too quickly and have reduced penetration or simply disintegrate on the target leaving you to face whatever it was you just shot with a serious reason to cause you harm. A bullet that it to strongly constructed my fail to expand at all. If it was originally of sufficient diameter this might not be too bad but if of a small initial diameter you may find yourself explaining your misdeeds to your target. Choose your bullets carefully.

My personal belief is if you have a rifle of a given caliber (say a .308 or .30-06), and you want (or need) something more powerful, what you need to do is to go up on either bullet diameter alone or bullet diameter and powder capacity and go to a .35 or so caliber. Don't waste your time burning more powder on a big bottle with the same bullet.

Of course, if you have lots of spare money and just have the need to have a whole bunch of different rifles to play with, be my guest. (...and you can send a couple to me so I can play too.)

I hope that the forgoing has provided some food for thought and I'm sure that I will be hearing from some of you. You can email your comments and ideas to me at [email protected].

Special Thanks to Mr. John Schaefer - a.k.a Father Frog

"This article was originally published on Fr. Frog's Home Page & is used here with his express 
written permission."   Fr. Frogs Home Page is at Web URL:

Article Copyright © 2002 - John Schaefer - All Rights Reserved.

THE 4 RULES: The 4 Basic Rules of Firearms Safety - If these four basic safety rules are established and followed, safe firearms handling will be assured and negligent discharges will be avoided.

1. Treat All Firearms as if they are loaded. 

2.  Never point a firearm at anything you are not willing to destroy.

3.  Keep your finger off the trigger until your sights are on the target and you are ready to shoot.

4.  Be sure of your target and what is behind it.

There is also an unwritten but implied fifth rule which applies not only to firearms safety, but also to tactics: Take nothing for granted. Check everything by sight and touch.  

For more information on Firearms Safety Click Here MORE




John Taliaferro Thompson

Brigadier General John T. Thompson
An Outstanding Military Career

By Tracie L. Hill

John Taliaferro (pronounced "Tolliver") Thompson was born in Newport, Kentucky on December 31, 1860.

He graduated from West Point in 1883, and became the youngest Colonel in the U.S. Army. He was Chief Ordnance Officer for General Shafter's Expeditionary Forces in the Spanish American War. It was there that he realized the necessity for increasing the firepower of the soldier, and began his quest for a more efficient small arms weapon.

Appointed Chief of the Small Arms Division of the Army Ordnance Department, he supervised the development of the M1903 Springfield Rifle, considered for many years to be the perfect rifle for military use.

Early in his new capacity, General Thompson believed that the only available means of equipping the greatly expanding armies of the United States with small arms was to adapt the caliber .303 Enfield to the caliber .30 cartridge manufactured in the United States. This would utilize existing manufacturing facilities for the continued production of both Springfield and Enfield rifles.

When World War I broke out in Europe in 1914, it became obvious that the production of military small arms on a large scale in the U.S. would become necessary. Col. Thompson resigned from the Army to enter this field, and was appointed Chief Engineer of the Remington Arms Co. While serving in this capacity he designed and build the Eddystone Plant at Chester, Pennsylvania, which at the time was the largest small arms plant in the world. Under his supervision, this plant manufactured great numbers of Enfield rifles for the British, and "Three-Line" (7.62x54R caliber) Moisin-Nagant rifles for Russia.

Upon the entry of the United States into the war in 1917, he re-entered the Service, reaching the rank of Brigadier General and as Director of Arsenals was placed in charge of all small arms production.
For his achievements he was awarded the Distinguished Service Medal by Congress.

By Tracie L. Hill
Thompson: the American Legend THE FIRST SUBMACHINE GUN

That area of the bore immediately ahead of the chamber. Lead or freebore; the unrifled portion of the bore immediately in front of the chamber. Generally very short.

TIMED FIRE: is a type of pistol match or a stage of the national match course of fire where a string of five shots are fired consecutively during a period of 20 seconds. A timed fire match is a series of four such strings and the National Match Course includes two strings.

TIMING:  The alignment of the chambers in a revolver with the bore.  In a revolver which has seen a lot of use, the timing can be "off," so that the chambers do not perfectly align with the bore, causing the gun to spit lead from the barrel-cylinder gap.  Timing is also important on many heavy and crew served machine guns like the Browning M2 .50 Caliber where the "Headspace and Timing" must be adjusted periodically to ensure proper ammunition feeding and function.

TOP STRAP: The upper part of a revolver frame, which often is either slightly grooved, the groove serving as the rear sight or which carries at its rearward end a sight that may be adjustable.

TOUCH HOLE: Small hole in a gun or cannon for igniting the charge.

TRACER: Slang for Tracer Ammunition.

TRACER AMMUNITION: A type of ammunition that utilizes a projectile or projectiles that contain a compound in its base that burns during its flight to provide a visual reference of the projectile's trajectory.  While it may produce an incendiary effect on a target it is not expressly designed to do so.  Caution must be taken when using Tracer Ammunition as range fires or brush fires can be easily started by the burning compound.

TRAJECTORY: The flight path of a projectile.  The vertically curved path taken by a bullet after it leaves the barrel of a gun.  Contrary to popular misconception it is not a straight line but rather a somewhat flattened curve that crosses the line of the sight twice.

TRAP: A shotgun shooting sport in which the competitors attempt to break frangible aerial targets going away from them at different angles and elevations.  It is an Olympic shooting sport. The term can also refer to the device used to throw the frangible targets also know as Clay Targets, Clay Pidgins and Skeet.

TRAPDOOR RIFLE:  Early American breech loading rifle where the breech block hinged forward to open like a trap door. Specifically the term refers to: U.S. SPRINGFIELD RIFLES & CARBINES PRODUCED BETWEEN 1865 & 1893. These single shot, black powder "breech loading" rifles were initially manufactured by converting American Civil War vintage muzzle loading rifles.  "Trapdoor" rifles were carried by many of the United States troops in the Spanish American War.

Model 1865 "Trapdoor" Rifle


The Civil War was drawing to a close, but far from over, when the War Department requested that the Ordnance Department develop a breech loading rifle for the military. To fulfill this request, the Ordnance Department sent requests for prototype arms to all the major arms manufacturers in the world and to anyone who would like to submit a test gun for trial. A number of private and commercial arms were received along with several submitted by Springfield armorers.

After a considerable amount of prototype testing, the breechloader submitted by Erskine S. Allin, Master Armorer at Springfield, was selected for its simplicity. Also, it could be inexpensively assembled using many parts from CW muskets. At this time, and for many years after the War, getting funds for new ordnance projects was a major problem.

5,000 of Mr.Allin's rifles were made and given the nickname "First Allin." The gun design was based on using Model 1861 muskets for its construction. Only the stocks and barrels had to be modified. The breech of the barrel was opened and fitted with a breech block which hinged forward, thus the name "trapdoor." The stock had to be cut to accept the ejector and extractor mechanisms. This process left only a very thin portion of wood covering the mechanism on the lockplate side of the stock. If a rifle had been used in service, this piece of wood is usually missing. The rifle was chambered for .58-60-500 rimfire cartridges. CW locks, stocks, barrels, trigger assemblies and bands were used in their production. This made the actual production cost ($5.00) far less than the cost of a new rifle.

It soon became apparent that many of the small working parts in the breech system were not going to have a long service life, and the action was too complicated for normal service use. Therefore, before the M65 production order was completed, the less complex M66 rifle,"Second Allin," was already being tested.

The Model 1865 rifle quickly became obsolete and most of them were sold in the 1870s to several American arms dealers. At the time, there was a large demand in the US, for shorter cadet style rifles. To satisfy this need, these dealers cut the barrels and stocks to make short rifles with 33" and 36" barrel lengths. Likewise, the stock wrists were often thinned for cadet use. These altered guns have marginal value and have caused the remaining few unaltered rifles to rapidly climb in value.

Information Courtesy Of:




By Patrick McSherry

This single shot, black powder weapon was carried by many of the United States troops in the Spanish American War. The weapon was outdated and put the troops using it at a disadvantage.


By the end of the American Civil War, the United States Army recognized the need to obtain a breech-loading rifle for its use. However, with the end of the war, funds were curtailed, and the army had an overabundance of muzzle-loading weapons left from the war. The "trapdoor" rifle denoting the method of opening the rifle at the top of the breech to load a cartridge, was developed and about 30,000 rifles were converted to "trapdoor" models, more properly called "Allin Conversions". By 1868, instead of converting old weapons into "trapdoor" models, a new rifle was developed using the Allin "trapdoor" mechanism. This weapon was the U.S. Rifle, Model 1868. This weapon went through a series of minor modifications (1870, 1873, 1879,1880, 1884 and 1889, as well as a few more specialized cadet and officer varieties), and was used for thirty years.

At the outbreak of the Spanish American War, the current model was the Model 1889. This weapon was the main shoulder arm used by the volunteer troops at the outbreak of the war, in spite of its being outdated in comparison with the smokeless powder weapons that were becoming available.

The modification that was the major difference between the Model 1873 and the Model 1889 was the replacement of the triangular bayonet with a rod bayonet, and a few other very minor modifications.


From the United States government's standpoint, one major advantage of the Model 1889 was that it had many of these weapons in storage, and they could be readily supplied to the sudden influx of troops. Many of the existing National Guard regiments already carried this weapon, so it made sense to continue arming their enlarged regiments with the same weapon.

The overwhelmingly major objection to this rifle was that it used black powder instead of the more modern smokeless powder. The black powder cartridge left a tell-tale cloud of smoke by which the shooter could be spotted and fired upon. Also, the smoke cloud required the shooter to wait until the smoke cleared before he could aim and fire again.

The weapon was a single shot whereas the newer Krag-Jorgensen and the Spanish Mauser rifles were magazine weapons. The United States, however, insisted that its magazine-equipped Krag-Jorgensen rifles be used as single shot weapons with the rounds in the magazine reserved only for emergencies. Still, in actual combat, the rate of fire of the single-shot Model 1889 "trapdoor" rifles was much slower.

The Model 1889 "trapdoor" rifle had an advantage in "take-down" power over the newer smokeless powder rifles such as the Krag-Jorgensen Rifle, used by some United States forces, and the Spanish Mauser because these weapons fired a smaller projectile. This difference in size and weight also meant that the average soldier could carry fewer rounds with him fo rthe Model 1889 than he could carry for newer Krag-Jorgensen Rifle (one hundred .30 cal. cartridges weighed the same as sixty .45 cal "trapdoor" rifle cartridges).

Lastly, the "trapdoor" rifles fired at a higher trajectory than did the more modern weapons, resulting in more difficulties in aiming.

Information Courtesy Of: The Spanish American War Centennial Website

Web URL:

A clay target shooting sport with a shotgun. Shooters fire at clay targets flying away from them. Shooters stand behind the trap at a distance from 16 to 27 yards.

TRAP STOCK: A style of shotgun stock with greater length and less drop designed for trap shooting.

TRIGGER: A small lever protruding from the action. Pressing the trigger causes the cartridge to be fired.

TRIGGER CONTROL: is the ability of the pistol shooter to apply pressure on the trigger to fire the weapon without disturbing sight alignment.

TRIGGER GUARD: This is a loop of metal which extends down from the frame and encircles the trigger. It is designed to prevent the trigger from snagging as the firearm is handled or as handgun is removed from or placed into a holster.  Some vintage handguns do not have trigger guards.

TRIGGER, HAIR:  A slang term for a trigger requiring very low force to actuate. Note: Hair triggers are frequently used on competitive target rifles and pistols for increased accuracy. The reduced force needed to pull the trigger allows the shooter. s firearm to remain steady.

TRIGGER JOB: Polishing or machining work done to lighten the trigger pull.

TRIGGER LOCK: Trigger locks can be purchased in a variety of styles, all of which secure the handgun by  immobilizing the trigger. The most common trigger lock design covers the trigger mechanism on either side with two steel or plastic blocks which lock together.  Most major manufacturers have been giving away trigger locks with new handguns for the last few years.  The locks can be purchased with either keyed or combination locks, and are designed to allow the handgun to be transported while locked.  Most trigger lock designs are easy to use, however, the owner of the handgun must actively install a trigger lock.  Trigger locks should never be placed on a loaded gun. For additional information see safety note below.


SIG Trigger Lock
Typical Trigger Lock on SIG-Sauer P239
Free from most manufacturers with new handguns

Some handgun owners may wish to use a trigger lock to secure a loaded gun.  In such cases, the risk of unintentional [read negligent] discharge is significant when installing or removing a trigger guard from a loaded handgun.  Reports of idiots negligently making there guns go bang while trying to put a lock on them come in often.  NEVER put a trigger lock on a loaded firearm!

Most Firearms Manufacturers include a free trigger lock with the purchase of a firearm.

When properly installed on unloaded handguns, trigger locks can reduce the risk of unintended discharge. Trigger locks prevent children of any age from using the gun, as long as the child does not have access to the key or combination.   Note: If the trigger lock does not fit the gun properly or is improperly installed, the trigger may still be operated. 

Never put a trigger lock on a loaded firearm.

TRIGGER PULL: Length of the travel of the trigger.   Force or weight in pounds needed to engage the trigger.  The average force which must be applied to the trigger to cause the firearm to fire. Note: Typically, non-target mode-firearms have a minimum trigger pull of 3 pounds. Double action revolvers often have a long, heavy trigger pull of around 10 pounds.

TRIM TO LENGTH: The length a cartridge case should be trimmed to after it has stretched past its' "maximum case length".

TRITIUM:  A radioactive isotope of hydrogen with atoms of three times the mass of ordinary light hydrogen atoms.  Tritium, due to its radioactive properties, glows in the dark and is the most common element used in "night sights".  Night sights are probably the most useful accessory on a combat handgun, as statistics show that 85% of gun fights occur in low light conditions or at night. 

TURRET PRESS: A reloading press with a rotating multi-station turret top for positioning dies and powder measure in their appropriate sequence.

TWIST: The rate of spiral of the grooves of a rifle barrel expressed in length of barrel per revolution. 2. The pitch of a firearm's rifling expressed in a ratio of turns per distance.   A 1:7 (1 turn in 7 inches) twist means that the rifling makes 1 complete turn in 7 inches. The optimum twist rate is determined by the projectile's length and diameter.

TWIST BARRELS:  A process in which a steel rod (called a mandrel) was wrapped with "skelps" - ribbons of iron.  The skelps were then welded in a charcoal fire to form one piece of metal, after which the rod was driven out to be used again.  The interior of the resulting tube then had to be laboriously bored out by hand to remove the roughness.  Once polished, the outside was smoothed on big grinding wheels, usually turned by water power.

TWIST RATES: The following is an explanation of the many twist rates found in AR-15 rifles barrels.


m4carbine.gif (14770 bytes)


1x7 - Technically too tight of a twist for any .224 bullet widely available, including the 80 grain.  Manufactured originally to stabilize the military SS109 and / or tracer ammo, but further military testing has shown other twists to be superior.

1x8 - Great twist for 69-80 grain bullets.

1x9 - Good all around twist ratio. Best suited for 52-69 grain, but either end of the envelope will be questionable.

1x10 - Practically the same as 1x9, but favors the lighter side a little more.  This is the twist rate of the vaunted Olympic SUM (Stainless Ultra Match) barrel.  

1x12 - Great for the 40-52 grain bullets. Most often found on bolt action rifles as their primary use is varminting.  All right for the 55 gr, but not the best.

1x14 - If you want to under stabilize the .224 bullet, use this twist.
Useless except for tumbling effect it causes upon bullet impact.

Barrel Twist Information By Corey Sattler - [email protected]

About the author: Mr. Sattler is the Law Enforcement Sales Manager and Archival Records Manager at Olympic Arms, Inc. in Olympia, WA and has been with the company since 1993.  He is also a Reserve Deputy in a small Southwest Washington county Sheriff's Office.

TMTW - 2MTW: Acronym for Two (2) Major Theater War.  Current U.S. Military strategy that mandates and plans for the ability to deploy to, fight and win a major war in two (2) separate theaters or geographic locations simultaneously. The TMTW strategy and many other defense plans and procedures are under review.

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