[Bainx]

What happens if you don't crimp a bullet? Loss of accuracy or what?

[KP95DAO]

First off, you don't crimp bullets. You crimp cartridge cases into bullets.
You do this for several reasons, some which are dual purpose.
(1) To help feeding. (2) To prevent the bullet from coming out of the case under recoil. (3) To prevent the bullet from being driven into the case under recoil or feeding. (4) To help facilitate the proper burning of the powder charge. (5) To prevent bullet movement during rough handling prior to being fired.

Any more out there?

[hardcorehunter5]

Also you can only crimp with bullets that have cannellure; otherwise you will damagethe jacket on the bullet. The only thing I would add to kp95dao is with proper burn, it also helps obtaining proper pressure, which in turn gives you the desired fps. I would not recommend not crimping bullets that are meant to be. It is possible that the case pressure may escape past the cannellure area during ignition. The result would be loss of accuracy and consistancy, because like kp95dao stated the burn needs to be burn as complete as possible.

[WESHOOT2]

I crimp uncannelured bullets in 357 Magnum (158g), 44 Magnum (240g), 45 Colt (230g), and all the 'auto' calibers.

I occassionally DON'T crimp both jacketed and lead bullets in all the 'auto' calibers.

Understanding begets silence...............

WHAT HAPPENS IF I DON'T CRIMP:

maybe I go Bullseye shooting; maybe I get stringing; maybe I get large deviations; maybe I find more accuracy; maybe I get unreliable feed; maybe some other stuff, like that posted

Conventional wisdom is not right just because it gets repeated.

:banghead:

[mete]

I,ve always used a taper crimp for autos. No cannelur is needed and you won't have problems headspacing.

[HSMITH]

The only way you are going to know is to try it. Be careful and watch for bullets being seated too deep and things like that.

[Nero Steptoe]

Neck-sized rifle cases don't need to be crimped; taper crimps don't require a cannelure; roll-crimping should be done into a cannelure; for rifle cases, the Lee FCD crimps fine without a cannelure.