I started crimping the cases of my 375 H&H magnum loads last week. The rounds are more accurate and the point of impact has shifted. Has anyone else had this happen? I had to shorten the AOL of the rounds to crimp them and I was wondering if it was the longer distance to the lands that has affected the accuracy and the point of impact rather than the crimping?

Thanks.

The golden rule when reloading is to never change more than one thing at a time as you won't know what caused the difference.

You will now have to go back to where you started, and do it over again.

On your rifle/load combination seating depth and crimping may/may not influence accuracy.

Johan

I do not believe crimping rifle ammo is better. I don't acccept the claim that crimping improves accuracy, particularly if crimping changes the bullet in any way! But, a heavy crimp is absolutely essential in some kinds of pistol ammo if one is to get complele burning of powders like H110 and WW 296!

Ron L,

We got LEE Factory Crimp dies for our big bore rifles. I didn't see much, but there was a little difference in P.O.I.. The biggest difference that I have seen was I had to back down my powder charge in to keep the same velocity.

(ie.) 104.5gr H4831SC down to 102.5gr. in my .416 Rigby. The .375 only needed a 1gr. reduction.

The accuracy has remained the same.

The price of this special die is approx. $25.00 and they will make you one if it's not listed in their catalog.

All the best,

SAM

I can say from my experience with pistol cartridges that crimping does help, at least with pistol rounds. I recently conducted and informal test using 3.6gr W-231, 148gr LDEWC, WSP primer in 357 Magnum cases. I loaded some with no crimp, some with just a hint of a crimp, some with a moderate crimp and some with a heavy crimp. I found those with a moderate crimp were more uniform in velocity and were just a little more accurate.

Saeed has some information about crimping, right here at this site. Scroll down to the bottom of this page to "accuratereloading.com," and look for FAQ's.