Shotgun barrel length 21 vs 28

steve45

I recently read that when shooting standard velocity target loaded 22 ammo that the bullet was at its fastest at 16 inches of barrel length and that it slowed down due to friction in longer barrels. Has anyone seen any info like this for shotguns? Might the standard upland game load, 1 1/8 oz at 1200 fps be faster in a 21 inch barrel than in a 28 inch barrel? Thanks, Steve.

beantownshootah

In fact, shotgun shells typically use fast-burning powders exactly like handgun ammo, and indeed pellet velocity tops off pretty quickly with conventional loads.

Its going to depend a little bit on load, backbore, and such, but max pellet velocity is typically achieved with 18 inch shotgun barrels, give or take a little bit.

The main point of longer barrels is to alter the guns balance and regulate the swing speed of the shotgun when pointing at moving targets. To a lesser extent longer barrels also provide a longer sight radius (or 'bead radius').

Yes, once you hit maximum velocity, longer barrels actually will decrease pellet velocity, but in practice the amount of decrease is negligible. Relatively heavy shotgun pellet payloads fired in plastic cups through wide smooth bores just don't encounter much resistance.

charliemeyer007

Shotgun powder burns fast. By about 16 inches it's burnt, small % velocity gains continue for a while as bbl length increases. My carry shotguns are 20 inch.

Riomouse911

BTS has it down, the extra barrel length is for balance and swing speed/follow through on moving targets like quail, ducks and clays.

Hawk Carse

Churchill (the British gunmaker, not the prime minister) did a lot of test firing and concluded that 25 inches was the optimum barrel length for a 12 gauge game gun. Long enough for the powder to burn and pressure to decay so as to not blow the pattern at the muzzle, short enough to be handier than the traditional 28-30 inch.

steve45

Thanks for the answers everyone. I'll be shooting a 21" barrel this year quail hunting and test this first hand.

beantownshootah

I'd say simply that the "best" barrel length is whatever works best FOR YOU in your given application. Ultimately it comes down to what you're trying to hit, what gun(s) you've got available, and what you're comfortable shooting. If you're consistently hitting with it, the gun is good.

Since the FUNCTIONAL difference in muzzle velocity between a shotgun with am 18" bbl and a 32" bbl is negligible, I'd say pellet velocity is really one of the LEAST important things to consider when choosing a barrel length.

The MOST important things in hitting aerial targets are stock fit (which is probably more important than EVERYTHING else), choke, weight and balance, and these last two are really where barrel length comes into play.

In practice, most people hit aerial targets better with longer barrels. That's why most people do their wingshooting guns with guns of 26" or more.

Consider that even though there is zero velocity or pattern advantage to having a long barrel, the top level skeet guys still like 30" or even 32" bbls, because they slow down the swing and make the gun point better.

Can you shoot birds with a 21" bbl gun? Of course. Some people like these because they're easier to carry and faster to get on target. Some people like 24-25" guns for upland game. Others find anything less than 26" to be too "fast" or "whippy".

This is really a matter of personal preference, and some of it may come down to simple anatomy (bigger shooters may like bigger guns, and vice versa).