Crimp or not Crimp up dated question

br549

i've read on several different die sets when loading rimless cartriges not to crimp. but to crimp rimmed cases. example 45acp,40s&w,3006, 308, 270 not to crimp. 38 spl, 357,30-30 444 marlin,crimp those. can someone who reloads lots suggest what i should do? thanks for any help.

RCrosby

There's no one rule to turn to. A lot of different cartridges and countless types of firearms they could be chambered in. Some general guidelines: heavy recoiling handgun rounds, crimp, rifle rounds to be used in tubular magazines, crimp. Bullets without cannulures, don't crimp, or if so, only with taper. Bullets with cannulures, it depends.
Might help in getting more (and better) responses if you narrowed things down to 1 or 2 cartridges and tell us what type of gun you'll be firing them in. There's lots more to it, but maybe this will get the ball rolling.

bpost

You DO NOT crimp a case that head-spaces on the mouth, like the 9MM and 45 ACP.

You should crimp lead bullets used in heavy loads on high recoil revolver rounds, like the 44 Mag and .357 Mag.

You should crimp hot revolver ammo with cannelures on the bullet.

You may crimp a bullet used in bolt action rifles if the recoil may cause the bullet to pull out, jamming the feed.

You may need to crimp for feeding in semi-automatic rifles.

You should crimp bullets used in dangerous game loads.

You do not need to crimp bullets used in single shot guns.

One test I used over the years is to load a round and push the nose against the bench with both hands. If the bullet went into the case easily, I annealed the brass and started to use a .0005 smaller expander ball. I personally only crimp hot loads in the handguns. Everything else is left natural, with about .002 bullet tension.

partisan

AMEN, to the last poster! This is what I have always done with my reloads.

RCrosby

Am I the only one who crimps my ACP rounds? Tapered, I'll grant you, but crimped none the less.

bpost

quote:Originally posted by RCrosby
Am I the only one who crimps my ACP rounds? Tapered, I'll grant you, but crimped none the less.


I should have clarified the difference. The cases that headspace on the case mouth may be taper crimped but should not be roll crimped.

br549

if say a 45acp or 40 s&w needs taper crimped how do you taper crimp?
i realize i would need a crimp die. thanks for any help.

5mmgunguy

If you buy a taper crimp die, they will give you directions with it on how to set it up. Basically you make sure the die is set so the taper part doesn't hit the case...seat a bullet the right length then back the seating plug and slowly set the die body deeper until you have your desired taper crimp...you don't want much, then run the seating plug down until it hits the bullet...now try it...if you don't like the results adjust the die a little...ps you are doing this part with empty cases...no powder or primer...only when happy with the crimp and OAL then use powder and primers.

perry shooter

Hello I also taper crimp 45ACP I make sure the case mouth is .001-.002 smaller then the area below the mouth where the driving band of the bullet is surrounded by the case . This will enhance feeding without deforming the bullet.. If you take two loaded rounds and hold up with sides touching and hole up to the light you will see just a crack of light between them at the case mouths. "PRAISE THE HARD-BALL GUN"