9mm loads bulging around case neck?

Shep546

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Hey guys, just reloaded 9mm for the first time.

I loaded 124gr FMJ rn bullets to an OAL of 1.135"

I noticed the case bulges a bit around the mouth when the bullet is seated... is this typical for 9mm reloads? Thanks.
 
Many straight wall cases will have an hour glass shape after being reloaded due to sizing then seating a bullet. Do you have a pic to post up for us?
 
RhI2qoo.jpg



My hand load on left, factory ammo on right...
 
Too much crimp?

Or I sometimes have this happen if the case is not slipped all the way into the shell holder and it is slightly misaligned as it strokes through the sizing die...

Edit, just saw the pic, I dunno
 
Hey guys, just reloaded 9mm for the first time.

I loaded 124gr FMJ rn bullets to an OAL of 1.135"

I noticed the case bulges a bit around the mouth when the bullet is seated... is this typical for 9mm reloads? Thanks.

Many straight wall cases will have an hour glass shape after being reloaded due to sizing then seating a bullet. Do you have a pic to post up for us?

It it looks like an olde tyme coke bottle, it's normal. If it's right at the case mouth, you might be over crimping. The case mouth should measure .380 or .379
 
Seat the bullets in one operation and then crimp in another separate operation, when you seat (push) and crimp at the same time the case can bulge.

Second, how can a case headspace on the mouth of the case when it's over crimped?
 
Looks great to me. If it chambers neatly, does not get stuck, hit the range and shoot the darn thing along with her 999 sisters!

If look matters that much to you, there are dies that neatly shapes finished rounds like factory rounds.
 
Second, how can a case headspace on the mouth of the case when it's over crimped?


Yep. It's hard to tell, but the factory bullet on the right looks like the case mouth may have been crimped to the limit.
As you note, 9mm headspaces on the case mouth, so the case shouldn't be crimped in flush with the bullet.


The bit of a bulge to the base of a reloaded round is common. Sizing dies often size a bit smaller just to make sure the case holds the bullet securely.


Seat the bullets in one operation and then crimp in another separate operation, when you seat (push) and crimp at the same time the case can bulge.


I do this with a seater die, and then use a Lee Factory Crimp Die to do a taper crimp and post size. Good for getting rid of any bluge at the base of a case if it was fired in a gun without a fully supported chamber (Glock)
 
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Use the factory round to set the crimp, back out seater put factory round in and screw down, once you feel resistance that should set your crimp.

Take your barrel out of the gun and test the round.
 
As to headspace vs. Crimp.....

This is why you typically taper crimp cartridges that headspace on the case mouth, and roll crimp cartridges that headspace on the rim. ;)

Two different crimps with very different appearances.

Taper crimp simply tapers the case mouth to ensure feeding more than bullet retention, and should be minimal IMHO.

Roll crimping can be applied much heavier and actually bites into the bullet, or fits into a cannelure, and provides retention, especially in magnum revolver/lever cartridges.
 
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