Problems reloading 300BLK

Has anyone had problems seating bullets, esp longer ones in 300BLK? About 6 out of 20 have folded at the shoulders like below. This was loading 220gr jword bullets (haven't decided on the mold yet to make proper boolits). It hasn't happened on the 150s so far. Using Hornady dies set to barely kiss it for a crimp. It occurs on both once fired 300BLK brass and on converted 5.56 brass. Am I missing something? If I were pushing for a lot of crimp, I could see it. I'll have a Lee factory crimp die in my grubby paws tomorrow, so I can see how that goes in comparison. Thanks for any insight.

Do you have too much neck tension? I would measure the inside of the case neck and start there, your sizing die may be too tight.

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Originally Posted by treadwm

Has anyone had problems seating bullets, esp longer ones in 300BLK? About 6 out of 20 have folded at the shoulders like below. This was loading 220gr jword bullets (haven't decided on the mold yet to make proper boolits). It hasn't happened on the 150s so far. Using Hornady dies set to barely kiss it for a crimp. It occurs on both once fired 300BLK brass and on converted 5.56 brass. Am I missing something? If I were pushing for a lot of crimp, I could see it. I'll have a Lee factory crimp die in my grubby paws tomorrow, so I can see how that goes in comparison. Thanks for any insight.

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Maybe chamfer the ID of the neck?

Pare you trying to seat and crimp at the same time?

What is the head stamp(s)?

Are you you wet tumbling?

There is a list of "good/bad" brass to convert here.

http://www.300blktalk.com/forum/view...?f=141&t=88599

The converted brass is PMC. Saw it was in the "good" list. Half of the failures were on R-P 300BLK. Cases are tumbled in corncob, lubed (Hornady OneShot), sized, trimmed to length and chamfered in/out.

guywitha3006, I'll check the ID next time I sit down to it. I did not think to check that before. I'm using boattails so they seat easy. But they are long boattails at that.

Thx, guys.

Are you using any expander plug or die to gently open the neck?

It was the crimp when I was having that problem. I had to get a Lee FCD. My redding dies would would do that if I seated and crimped at the same time.

No. This small test batch was done on a single stage while I work up the loads.
Was trying to nail down the load before messing with setting up the Dillon. The powder funnel would open it a bit. Plus I have a Lee factory crimp coming so I can set the Hornady to just seat. I'll set the Dillon up and try again.

Prob the combo of snug neck tension and trying to seat/crimp a long boattail in one operation is what brought it on. Apparently with shorter bullets I can get away with it. Any suggestions for an expander to use on the single stage press? Does the generic Lee work well enough? Thinking it might be handy to have when doing small test batches.

I swapped out the powder funnel in my lee powder drop die to one or a 32 S&W. There was a slight modification but I cant remember what it was. It works like an M-die, but much cheaper and more consistent than the lee universal neck expander. Look around, the information is on this board on what I did. I just followed someone else's work that did it here.

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Originally Posted by Negster

It was the crimp when I was having that problem. I had to get a Lee FCD. My redding dies would would do that if I seated and crimped at the same time.

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Forget the crimp and just "press check" the finished rounds for neck tension.

I've seen this, too.... I always attributed it to variations in the case length. On long bullets without cannelures, the crimp goes from "not enough" to "crushed shoulder" in about .010" of depth... So I test a few and make sure there's no crimp on the longest cases and call it good... Occasionally, an exceptionally long case sneaks through and the case folds. I grab the bullet-puller and disassemble them at the end of the session, then run them up the sizing die again without the deprime punch... Adjust length, rinse and repeat...

I believe case neck walls are too thick and may require neck turning.

There is no need to crimp .300 BO -in my opinion. I never have and have zero problems with my loads. Best, Thomas.

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Originally Posted by Texas by God

There is no need to crimp .300 BO -in my opinion. I never have and have zero problems with my loads. Best, Thomas.

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^^X2
I have Hornady 300aac blackout dies and could never get a crimp with them with out the buckle in the shoulder

For jacketed I do not crimp ----> just check with a push test

for Cast now using a lee crimp die on the cast loads that need it (smaller dia boolet)

Made up a dummy round to get seating depth correct. Within a few min of handling the bullet was pushed into the case. So I assumed a small amount of crimp was necessary. Not that there's much further in the case for a 220gr bullet to go when it's sitting on 11gr of 1680!

If you want to crimp, use the Lee FCD and just add an additional step. I've never had an issue with the neck tension for these cases and have had zero issues reloading for them.

Matter of fact, loading with 296, I'm able to churn out a bunch of high quality ammo in short order. There isn't much of a shoulder and runs through my press like water.

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Originally Posted by treadwm

Has anyone had problems seating bullets, esp longer ones in 300BLK? About 6 out of 20 have folded at the shoulders like below. This was loading 220gr jword bullets (haven't decided on the mold yet to make proper boolits). It hasn't happened on the 150s so far. Using Hornady dies set to barely kiss it for a crimp. It occurs on both once fired 300BLK brass and on converted 5.56 brass. Am I missing something? If I were pushing for a lot of crimp, I could see it. I'll have a Lee factory crimp die in my grubby paws tomorrow, so I can see how that goes in comparison. Thanks for any insight.

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I have had that problem with calibers other than the 300 BO. The issue was easily resolved with the Lee FCD. Adjust it according to your desires. I don't crimp anything, pistol or rifle with the seater die. I am a big fan of the FCD and have been for many years.

trying to seat/crimp a long boattail in one operation If you taper or roll crimp the case length has to be exact. If they move after seating, no crimp, your sizer die isn't right. Try it without the spud and with, check seating force. Might check the bullet OD. Can't tell for sure if that is a crimp ring or buckled lip for the loaded one on right You can crush the shoulder with the FCD. Typically, PMC is thicker brass when converted, R-P factory tends to be thinner. I FCD all rifle brass to make sure it chambers - even 308.

Problem is definitely related to neck tension. Adjusted the die to only seat the bullet. 150gr seated no problem. 220's either mushroomed the shoulder of the case a little or put a ring dent in the bullet itself. So the 220's are shelved until the proper Dillon powder funnel comes in.
Got the Lee FCD in this week. The 300BLK version works just as nice as my 9mm one. Leaves a neat crimp without any fuss or drama.

Thanks to everyone who chimed in and shared your advice and experience. Much appreciated!