New Bullets, New Issue

Hi All-

I am trying to load 9mm using coated 124gr bullets for the first time, instead of Berry's plated 115gr 9mm.

Many of them will not fully seat into a test gauge or my chamber, some are fine. I also tested my empty sized/primed case in the chamber, they're fine.

This is happening with, SIG, S&B, CBC and PMC brass.

I tried a longer factory round, it slides into the chamber easily. This feels like a bullet issue to me? Any ideas?

COL: 1.12
.002 crimp (.378)
Brand: Summit City 124gr .356 width

 

Seat them deeper. Not the same bullet but I have to seat mbc lead rn to 1.060 to chamber in my czs. Where are your coated bullets from.

 

Summit city.

 

Is the ojive diffrent, is the bullet larger in diameter. Is the fit on your seating die not as good so now your getting bulges????

 

I wondered all these things too. I have no 9mm ogive gauge, diameter the same as Berry's (Which has always worked 100%), and I measured several of the bullets, they were from .356- .356.5. I also rana few Berry's, they were fine, so the seating die should be good.

 

Put them side by side with a berrys. The straight portion on summits is long. What load are u using.

 

4.8- 5.2 of Unique ( Lee powder drops suck).

 

Of course. I should have surmised that. Never loaded anything but 115gr. before. More mass, gotta be longer. And yes, the ogive is very different.

 

Do you have a lee sizing die. Might see if running them through makes them more consistent and eliminates your issue

 

What oal will plunk for ya.

 

1.12 is the lowest OAL I see in my manuals/Alliant's site, I am at 1.10 now, and still not all the way in the chamber. Not sure how low I can go. Maybe saving 3 cents a bullet isn't gonna be worth it in my case. These have a far wider SD in weight than Berry's too.

 

Maybe not. Did u ask them a recommendation. Are you shooting a cz by chance.

 

Glock bulge ... bust it

 

No both counts.

 

Canik TP9SFX, about 1500 rounds through it.

 

This is interesting, VP9 barrel, about 50% seat:

 

This may fix it. Shorter OAL.

 

I'm on the fence about pulling these now. No problems before, now problems. They obviously don't fit the barrel, Berry's does, same diameter. That leaves me thinking, so if the coating has to be thicker than plating to work, how consistent is this coating, in thickness?

Not tryin' to slam Summit, they shipped fast, great prices, but maybe not my solution.

 

Seat them till they plunk and let us know oal.

 

It may just be the way I am seeing it, but your first pic, does it appear to be that I see that all the flare hasnt been removed...?

 

No, definetely removed, but I got those shiny crimp bands, which I never get.

 

Overcrimped and slightly buckled the case...?

 

The shape of the nose is different and wider with the heavier bullet. The bullet has to go deeper into the case. If you think things are bulged take a seated bullet out of the case and see if that case still fits. If it does the bullet needs to be seated deeper. Make sure you account for the reduced inside depth when working up your charges.