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 More recoil, short barrels or long barrels?
chwi548  [Member]
8/7/2008 7:50:04 PM EDT
On another thread on here, a poster is saying that Short barreled guns have less recoil than Long barreled guns because of the less velocity. I know that there is more muzzle blast, and when I've shot shorter barreled guns there is always more recoil.

I suck at math, so I don't have the formulas and physics to demonstrate it. Can anybody help? If I'm wrong or right, I want to show it either way.
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StealthyBlagga  [Member]
8/7/2008 9:00:39 PM EDT
Not enough info - it depends on the relative weight of the long and short guns, the barrel lengths, the type of ammo (fast buring vs slow burning), shooter perception etc. etc. etc. My 7.5" AR15 SBR in 5.56 kicks a lot less than my 16" AR15 with the same ammo, if this is helpful.
AngeredKabar  [Team Member]
8/7/2008 9:19:04 PM EDT
I've shot a 20 inch AR, 16 inch AR, and a 7.5 inch AR pistol.

Don't really have a good way to gauge recoil between the pistol and the rifles, but I'd say the 20 inch had less recoil. Then again, this is entirely dependent on the AR platform. YMMV.
chwi548  [Member]
8/7/2008 9:26:41 PM EDT
The thread in question he says that a AR SBR should have less recoil than a 16 inch barrel.

I brought up examples of 2in-snubby vs 8 in barreled revolvers. He said weight negated the differences.

I brought up the differences of shooting slugs with a 14 vs 20 inch 12 gauge, or a 20 inch vs 28 inch to eliminate the weight issue. He said shotguns don't count.

Basic info should be basically a Commando SBR vs an M4 or M16. Pick a standard ammo, like 55 FMJ. What other variables do you need?

rxdawg  [Team Member]
8/8/2008 5:48:09 AM EDT
In a AR, my SBR has a little (very little) more felt recoil than my 20". I think its mostly a weight issue.
SpacemanSpiff  [Member]
8/8/2008 6:38:51 AM EDT

the longer barrel will accelerate the projectile to a higher velocity, producing higher momentum, hence higher felt recoil, but longer guns are usually heavier so still feel like they recoil less.

Also, in autoloaders, the velocity of the bolt group during the firing cycle varies from gun to gun depending on how the gas system is set up, and that effects felt recoil as well.

If you had two bolt guns, one with a 10 inch barrel and one with a 20 inch barrel, and they were the exact same mass and fired the exact same load, the short barrel gun would have slightly less recoil due to the lower projectile exit velocity.

Chris_1522  [Team Member]
8/8/2008 6:44:32 AM EDT
I know my M44 Mosin Nagant has more recoil than my M91/30, and with its side-folding bayonet, it weighs about the same as its longer cousin.

I guess that shorter barrels are louder and have more recoil because the muzzle blast is higher pressure than with a longer barrel, despite the lower velocity of the projectile.

ETA: It appears the M44 weighs .2 pounds MORE than the longer-barreled M91/30.
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