Cutting down shotgun. 12" or 14" ??

[kengps]

I'm making a short-barreled shotgun on a BATF Form 1. The factory Benelli "Entry" guns are 14". But I would like to remove the mag extension and have a 12" 4+1. Anybody have ballistic data for any short shotties? I have read that Remington says it takes 10-12 inches for modern shotshells to burn completely. Any advice appreciated.

[CAcop]

If you are really worried about getting max burn from your shotshells call up the ammo companies. I think the question is too technical for anyone outside the factory to know. If you think about it they are the only ones who know exactly what they are putting in their ammo.

The flip side is to not worry about it and make it as short as you want it. If you think about it you are only taking off 2" extra. That cannot take much off the projectile(s). Reduced recoil/tactical rounds are 1100 to 1300 FPS and standard is 1400 to 1600. The velocity changes but the effects downrange are about the same.

[kengps]

Well....I found some useful data. A guy has a 10.75" barrel and says you need 3" magnums for it to cycle reliably. I guess I should just do what the factory did. 14". I want to shoot reduced recoil rounds with it. Might just have to install a wolf 25% less power recoil spring. I did find some ballistics data comparing a 14" barrel and an 18" barrel while shooting 1 ounce reduced recoil slugs. 18" was 30" penetration, and 14" was 27.5" penetration. Not a big difference. Also talked to a guy who owns a class III gun store. He has 3 or 4 he rents out to customers with 14 inch barrels. Says he has no flash problems at night from the shorter barrel.

[josp]

I use a Serbu SuperShorty for a breaching tool at work, and home defense. It has a 6.5 inch barrrel, but it is also a pump so I don't have the feeding problem you may encounter. Yes, at night there is a large flash, more with Remington than Federal Tactical buck. Pattern wise, it's better than the standard 20" Rem 870 issued, but I'm sure the penetration is reduced. In any case, it penetrates far enough in my non scientific tests (putting down injured deer) that it will do the job if needed.