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CAS TOPICS => The Powder Room - CAS reloading => Topic started by: MikeM. on March 11, 2025, 11:13:21 AM

Title: To Crimp or Not to Crimp
Post by: MikeM. on March 11, 2025, 11:13:21 AM
Do I need to crimp my cowboy revolver loads ? Seems like my brass would last longer if I didn't crimp but not sure if I should stop or not
Title: Re: To Crimp or Not to Crimp
Post by: Ya Big Tree on March 11, 2025, 02:26:48 PM
Most folks use the same ammo in their revolvers and rifles. So you would want a good crimp so the bullet doesn't get set back into the case in the rifle magazine tube. That will cause big problems. A good crimp will also help with ignition.
 
Title: Re: To Crimp or Not to Crimp
Post by: Abilene on March 11, 2025, 03:08:23 PM
Brass already lasts a long time with cowboy loads.  I would crimp everything. Uncrimped may not even chamber in a revolver due to the mouth flare.
Title: Re: To Crimp or Not to Crimp
Post by: MikeM. on March 11, 2025, 05:06:01 PM
Ok , I don't have a rifle in that caliber but will continue to crimp my loads .....Thanks Guys
Title: Re: To Crimp or Not to Crimp
Post by: Hair Trigger Jim on March 11, 2025, 05:08:13 PM
If you're having brass failures, you might be able to lighten up your crimp.
Title: Re: To Crimp or Not to Crimp
Post by: Coffinmaker on March 11, 2025, 06:40:32 PM

 :) MikeM ;)

There is really no caliber distinction.  It also doesn't much depend on your choice of powder.  Without a crimp, you may well run into Premature Shot Start due to incomplete ignition.  With Premature Shot Start, the bullet begins to move then stops as initial pressure drops and then the bullet acts as a bore obstruction and chamber pressure can go thru the roof.  So, Crimp.

As mentioned, in a rifle, lack of a crimp with straight wall cases, the bullet can telescope back into the case (called a turtle) and jam the rifle.  In a handgun, you may experience bullet creep where the bullet creeps forward in the case from recoil inertia, and can creep forward far enough to jam the cylinder.  So, Crimp

Just enough case belling to allow the bullet into the case.  Don't over work the brass.  I have cats I have been reloading for 30 years.  Brass really isn't "that" expensive.
Title: Re: To Crimp or Not to Crimp
Post by: Abilene on March 11, 2025, 07:00:31 PM
Quote from: Coffinmaker on Yesterday at 06:40:32 PM...I have cats I have been reloading for 30 years...

This brings up some interesting questions.

 :)
Title: Re: To Crimp or Not to Crimp
Post by: MikeM. on March 11, 2025, 07:18:59 PM
Will definitely crimp !! No, 45 Spc. Brass isn't expensive
Title: Re: To Crimp or Not to Crimp
Post by: Reverend P. Babcock Chase on March 12, 2025, 09:07:46 AM
Howdy Mike,

FYI, I load .45 and .38 for cowboy and rather than a roll crimp I taper crimp my loads. My brass has lasted for a decade or more. In addition, I don't experience any of the problems mentioned regarding not crimping. Also I use a Lyman "M" style 2 step neck expanding die. With that the second step enlarges just the mouth area to accept the bullet with no flare. I believe the combination of the two dies contributes to the longevity of my cases.

Just a thought
Rev. Chase
Title: Re: To Crimp or Not to Crimp
Post by: MikeM. on March 12, 2025, 09:35:11 AM
Thank you for the input