Champfering 9mm brass

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Pahonix

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At what stage do you do it? After deprimed/resize? Before or after tumbling? Before or after belling?
 
If I'm loading cast bullets in any handgun cartridge, semi or revolver, I chamfer the case mouth. It helps minimize shaving of lead off the bullet upon seating. Chamfering gets rid of the sharp corner of the inside of the case mouth.

Generally, it only needs to be done once and can be done about anytime the spirit moves you.

I do not trim semi-auto cases but I do trim revolver cases that will fire full power charges. A uniform crimp from case to case is necessary so they get trimmed. The case mouths have to get chamfered to remove the flash from trimming.
 
@cfullgraf @AJC1 Why the distinction of chamfering when using cast bullets? I flair the case mouth to seat bullets, I don't chamfer the case to guide the bullets. If the brass is trimmed I debur it, but the flaring/belling of the case mouth by the expander die supersedes any chamfer.
 
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@cfullgraf @AJC1 Why the distinction of chamfering when using cast bullets? I flair the case mouth to seat bullets, I don't chamfer the case to guide the bullets. If the brass is trimmed I debur it, but the flaring/belling of the case mouth by the expander die supersedes any chamfer.
I just like to knock down any sharp edges. I powder coat so shaving means barrel scrubbing. That's about as much fun as dishes.
 
For 9mm
Quick wet tumble after bringing it home form the range
Resize/Deprime wet tumble again
Sort by head stamp
Case gauge brass, toss bad ones
Uniform primer pockets
Trim to length
Chamfer case mouth
Weigh same head stamp brass, toss out any that are more than +-3gr from the average weight
Weigh all powder charges when loading
Weigh all bullets remove any that are +- 1.5gr from the average
Load ammo
Case gauge loaded rounds
Place in boxes
Place boxes in ammo can with moisture absorbent
Wake up realizing I was having a bad dream.

In truth I do some of the above;)
I am over 60 and life is to short to mess with 9mm brass much, I have rifle brass for that.
9mm, clean, toss steel/AL/ones with ledges, load shoot, repeat (I do case gauge since I use scrounged range brass)
Never measure it or trim it (except when I made some 9mm MAK brass)
I don't sort by head stamp but I can understand why some people who do. (I would be hard pressed to shoot the difference, and sure can't when shooting USPSA)
 
Thanks everyone for the replies.

A buddy recommended it because I'm getting little scrapings after crimping.
 
@cfullgraf @AJC1 Why the distinction of chamfering when using cast bullets? I flair the case mouth to seat bullets, I don't chamfer the case to guide the bullets. If the brass is trimmed I debur it, but the flaring/belling of the case mouth by the expander die supersedes any chamfer.

I just like to knock down any sharp edges. I powder coat so shaving means barrel scrubbing. That's about as much fun as dishes.

Also, besides not shaving ther bullet, chamfering the case mouth allows me to flare less which works the case mouth less.
 
If I am loading SD ammo for myself, I will chamfer the inside of the case at the primer hole to knock off the "hanging chad" left by the punching process. That is the only chamfering I do, and that is the only instance in which I do this.

The RCBS Case Prep Center includes a neat tool to do this.
 
All the above posts are dealing with chamfering case mouths. When I first read the thread title I immediately thought; "Case mouth or primer pockets?". I have a bunch of NATO 9mm brass that needed primer crimps removed. Tumbling and removing primer crimps is about all I do to my handgun brass...

The answer for "scraping or shaving" bullets is more flare. But if you want to chamfer the case mouths, go ahead. It won't hurt anything unless you cut enough metal to make a sharp edge on the case mouth...
 
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Thanks everyone for the replies.

A buddy recommended it because I'm getting little scrapings after crimping.
I don’t chamfer unless I trim, and I don’t trim 9mm. Do you seat and crimp in the same step? Can you tell what the scrapings are - from the brass or the bullet? Show pictures and we can try to help solve the real problem. Good luck.
 
I did when i first started. But after reading on here and seeing some video's, I decided it wasn't necessary for my 9mm loads. I just bell them enough to where it starts to seat slightly with a squeeze from my fingers. too much and I can hear it scraping in my die. I do get tiny tiny shavings of brass when seating and then crimping.
 
A buddy recommended it because I'm getting little scrapings after crimping.

I assume that you are seating and crimping in the same step. Longer pieces of brass get crimped a little more while the bullet is still being seated causing the shaving. Chamfering will help minimize the shaving. A better solution is to seat and crimp in two steps.
 
We shouldn't be putting so much taper "crimp" on a 9MM that we would shave a bullet even when seating/crimping together. That said, I usually crimp in a second step because I have the space on the LNL to do it.

Some thoughts on crimping in one or two steps.
 
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