Trimming

[Buckylou]

Do you have to trim 9mm cases?

[bogey1]

Nope.

[Buckylou]

Thanks. Doesn’t the cases have to be same size when crimping?

[Gunowner99]

You have a go/no go gauge?

[Buckylou]

No sir

[bogey1]

Thanks. Doesn’t the cases have to be same size when crimping?

OAL is the important issue, crimping is just that. Ive never seen a bullet
(9mm) with a crimp groove like rifle bullets, so it doesnt matter where its crimped
to an extant anyway. I have rifle bullets that are crimped above/below the groove
due to the OAL. Just dont over crimp.

This is my understanding and the way Ive been reloading my 9mm.

[frankski]

You don’t crimp 9mm or any other case that indexes on the case mouth. Just remove the bell.

However, if your case is too long, it may not fit the chamber. If too short, it can create other problems with firing and ejection.

I sort 9mm and discard any out of spec.

[cephas]

Case gauge as mentioned is optimum. A caliper could be used to measure each case.
Loaded round can be checked with the plunk test.
Pull your barrel, drop load into barrel. Cartridge should fall in, spin freely and drop out when you invert the barrel.
Explanation with pics: http://www.shootingtimes.com/editori...unk-test/99389
Figure-1-Plunk-Test-Brad-Miller.jpg

[wanneroo]

There are some reloaders who might load a box or two of handgun ammo and will trim their handgun cases for uniformity.

I don't have time for that crap. I load thousands of 9mm at a time and trimming cases provides no real benefit.

Every single round I load I check in a case gauge at the end. Maybe 1 out of 150-200 rounds fails the case gauge for whatever reason(make sure you keep your case gauge clean too) and so be it.

[Nate7667]

99% of the time you will loose the case or the primer pocket will be so worn out that the primer damn near fall, you will throw it away before trimming auto pistol cases.

Also, get yourself a Lee Factory Crimp die.
This will take the bell out of the case mouth and you can adjust it to the ever so slightest taper crimp. Never use a roll crimp on auto loading/rimless cases.