experiments comparing barrel length to velocity. Handguns, shotguns, and rifles have all been subjected to the hacksaw as inches were removed and the gun test fired. Then another inch or two is removed, the muzzle is properly deburred and crowned, and another series of test shots and chronograph readings are taken. For the most part, the testing confirms what the industry
has known for years. The shorter barrels produce less veloc- ity. Interestingly, in most calibers the drop in velocity and accuracy is small enough to be of little concern for hunting at normal ranges. Hunters who seldom shoot more than 100 or 150 yards will be about as well off with a 20- or 22-inch barrel as a 24- or 26-inch barrel. The loss in velocity will, in most cases, be small. There will be an increase in muzzle blast because the muzzle is closer to the shooter’s face, but, as with the velocity loss, it will be small. For example, testing by Springfield Armory with the
.30-06 cartridge produced 2,710 fps with a 24" barrel; 2,775 fps with a 28" barrel; 2,830 fps with a 30" barrel; and 2,848 fps with a 32" barrel. If rifle barrels in calibers of .30-06 and larger are shorter
than 22" to 24", the muzzle blast can be disturbing. From a ballistic point of velocity and energy, the shorter barrel may be satisfactory. It will be fast handling and light to carry. From a practical point of view, a rifle that has to be carried over any distance may as well have a short barrel. The shorter barrel probably will have only about a 25 fps drop in muzzle velocity for each inch less barrel. Of course, as with all gen- eral rules, it will be just an estimate or approximation. As always, a compromise is required for the performance area the shooter believes is most important. Note: A 2" difference in barrel length may have little
effect with a rifle or a shotgun, but with a handgun the dif- ference between a 2" and a 4" barrel can be dramatic. Originally, in black powder days, long barrels were
Sierra BlitzKing and Varminter bullets are the most effective bullets for varmint and small game hunting. BlitzKing bullets have a MatchKing jacket for optimum accuracy and an acetyl resin tip for explosive expansion. Varminter bullets are designed with a thin jacket to enhance expansions over a wide range of velocities. Now available in .20 caliber to .30 caliber. When you get ready for your next hunt, go-pher accuracy.
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078.27306 Gopher_Varmint
Hunter_3.625x10.125.indd 1
used for three reasons. (1) They were helpful in burning the powder. (2) The long distance between open sights was helpful in aiming. (3) It was safer for using bayonets because it kept the opponent farther away. (If the soldier was both good and lucky.) There is barrel whip, flex, warp, and the movement
and stress created by the hot expanding gas and projectile movement to consider. Technically, this physical motion will be less in a shorter barrel than a longer barrel, all other things being equal. Once again, the amount of reduction will be small. The maximum velocity for any given barrel length will
vary with the powder, bullet, cartridge type, manufacturer, and other details. As long as the barrel length does not exceed the opti-
mum length, (which it seldom will in any cartridge except a .22 RF) the bullet will continue to accelerate as long as it is in the barrel. After exiting the muzzle, the deceleration begins and the velocity starts to drop. The highest speed is at the muzzle, with the noted exception of an excessively long barrel. While testing typically gives answers in velocity read-
ings, the velocity directly influences energy (or power, if you prefer that word). Question: I recently met someone who asked how far
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