Rifles, to crimp or not

[wistlepig1]

On a bolt action rifle is there any need to crimp a cast bullit? If yes, How much of a crimp, almost none, light crimp, or heavy crimp? And what effect is there to crimping a case bullit. My thinking is just enough to hold the bullit in place while chambering but I would like to hear what others do and why. Yes I did do a search and didn't find the answers.

[tg32-20]

Your thinking is correct, just enough to hold the bollitt in place.

You may find that you need more crimp to get the pressure up enough to get complete burn on the powder.

Tom

[RickinTN]

For bolt actions I don't crimp. Usually I don't even run it through the crimp die enough to straighten out the flair left by the "M" die. For lever rifle cartridges I do apply a light crimp to keep the bullets from being pushed into the case from being put into a tube magazine.
Rick

[35 shooter]

I hate putting a crimp on rifle boolits in single shot or bolt guns. But i have to admit my accurracy increased after doing so. With j words i always seated to touch rifling a bit and no crimp but with cast (in my rifle) for whatever the reason, i had to use the crimp whether boolit was touching rifling or not to get best accurracy and best powder burn. I still try to get by with as little crimp as possible. I'd try it both ways and see which shoots best in your rifle. Of course on a hard kicker the crimp may be neccessary anyway just to hold boolits in place from recoil.

[TXGunNut]

Seems to be an individual rifle thing. So far all my CB rifles need at least a light crimp, leverguns seem to like a light to moderate crimp. I depend on neck tension for holding the boolit in place but a light crimp seems to help promote a uniform burn with at least one rifle I'm toying with.

[Shiloh]

I just close the belled cartridge mouth.

Shiloh

[44man]

The fellas are correct, just try both ways. Cast can move easier out of the case then jacketed so it depends on your case tension from your dies.
Everything comes into play, lead hardness, case size, powder used, primer used, lube used, expander used and on and on so there is nothing there anyone can answer.

[btroj]

I have been known to not remove the expanded case mouth in some cases as the belled mouth can help center the neck in an oversized chamber. Won't work in some guns as the mouth might hang up in feeding but I don't feed from a magazine off the bench in most cases anyway.

[lotech]

I've found it best not to crimp any rifle bullet, cast or jacketed, unless necessary.

[wistlepig1]

Thanks for the answers and I was just thinking about it as doing some loading the other night. It never hurts to ask, I have found out I was doing some things for years that were not "best", that's what I like most about this site.

[dverna]

I am not sure if a general statement can be made. A crimp will prevent bullet set back if that is an issue with the setup you are working with - but a non-issue with a single shot rifle - regardless of how much it recoils.

I will be working on cast bullets for the AR15 and will likely crimp to start with because of possible set back. I crimp bullets on the .30/30's. I do not crimp very much at all on the .308.

All the pistol caliber rifles I have are lever actions and they get a "good" crimp.

Don Verna

[Shuz]

As others have said, it's an individual rifle and type of ammo thingy. I have been playing around with cast boolits in the .250 Sav cartridge for years. I load them in single fashion so crimp is not really needed for recoil considerations, but I occasionally crimped some and could notice no real difference in accuracy from those that were not crimped at all. This is with 3 or 4 rifles in this chambering I've used down thru the years. One thing for sure.....to get a consistent crimp, all case lengths need to be the same.