10mm Auto brass trimming

[46and2]

How often do y'all trim 10mm brass ?

I've been working through 1000 pc of new Norma brass so it'll be a while even with three 10mm pistols.
Thanks in advance.

 

[Aaron23]

Never?

What am I missing here?

 

[SeabeeKen]

As with anything, when it needs it.
Had 1 45 acp the other day that needed a trim

 

[Aaron23]

As with anything, when it needs it.
Had 1 45 acp the other day that needed a trim

Guessing you use your barrel as a gauge to see if needs trimming?

I would caution op against trimming too short. In my experience auto brass that is excessively short will cause false pressure signs on the primers. (Flat primers in loads that in no way ‘hot’)

 

[kenhwind]

Probably doesn't ever need to be trimmed. But I do remember loading some 10mm and one case was a tight crimp, I mean a big difference and yep, that case was too long.

 

[bozo699]

I’ve loaded some extremely HOT loads with AA#9 and 220 grain hard cast bullets multiple times with no case failures and no trimming yet.
Wayne

 

[jk80]

Every pistol round i shoot have never been trimmed. Between loss and eventual cracked necks it kind of takes care of itself.

 

[243winxb]

The too long brass will find you, when its to long.
When a bullet gets crimped in the chamber, pressures go up.

The 45 acp is the only one that gets shorter. I have had to trim 9mm. Dont own a 10mm. See post #5.

10mm chamber.