To crimp or not to crimp

Anything to do with Lever Action Guns

Moderators: Regnier (gunrunner), JohnK, Sure-Shot

Post Reply
Posts: 21
Joined: Tue Dec 05, 2017 1:21 pm

To crimp or not to crimp

Post by Scotty » Mon Apr 09, 2018 5:29 am

I would like your opinions on crimping. I read in a reloading manual that crimping can increase accuracy. I am talking a lever 25-20 for this subject. I have not been crimping since I single load while working up a load. Also, will crimping shorten case life? Your opinions will be appreciated, and interesting, I am sure.

User avatar
Distinguished Expert
Posts: 2433
Joined: Sun Nov 10, 2002 1:22 pm
Location: Portland, Oregon

Re: To crimp or not to crimp

Post by marlinman93 » Thu Apr 12, 2018 9:44 am

I'd normally always crimp in a tube magazine, but if you load singly it's not necessary. Crimping may or may not increase accuracy, as that is dependent on the gun and the chamber, barrel lead, and throat. I load mostly for single shots in my Marlin Ballard and Remington singles. I rarely do even a slight crimp and set my dies to just remove enough case bell to allow the rounds to chamber. How much is removed depends on each gun's chamber, and what it needs to fit. Having the case mouth fit the chamber perfectly ensures the round is also centered to the bore when loaded, and usually gives the best accuracy.
Crimping and belling cases too much will indeed take it's toll, and will reduce case life by work hardening the brass. But probably not significantly enough to notice, unless you over bell or over crimp. Full length sizing will reduce case life much more, and I avoid sizing any more than is necessary to chamber a case. In most instances I don't size at all, but occasionally a slight sizing is needed to make a case slide in without too much resistance.
Marlin lever actions 1870's-WWI, Ballards, and single shot rifles!

Post Reply