dwak280530
dwak280530
1 post
Joined March 2015

9mm Failing to Fully Load

Hello,

I’ve been reloading for many years (mostly 9mm, 45ACP and 38Super) and I’m having a problem with my 9mm reloads recently that I’ve never encountered before and am looking for some help.

I just finished off my last 1000 or so rounds of 9mm with no issues and started to load a new batch and am having problems with the ammo feeding my M&P Shield and my Sig P229.

I use a Dillon XL650 with Dillon dies and the components are as follows:
Brass - various types that I collect at the range,
Bullets - Berry’s 124gr FMJ Round Nose
Powder - 5.0gr Winchester 231
Primers – Winchester Small Pistol

This is the same combination that I’ve always used with no problems, which is why this is so perplexing.

The issue is that the rounds (about 30-40% or so) fail to fully load into the chamber. When I inspect the round, I see some gouging of the bullet right about where the case mouth is. I can send a picture if it would help.

I’ve checked all measurements using a caliper and they match the prior reloads and some Winchester factory ammo I have.

Any thoughts/suggestions as to what the issue could be would be most appreciated.

Thanks for taking the time.

Doug
Bucolic_Buffalo
Bucolic_Buffalo
64 posts
Joined June 2016

RE: 9mm Failing to Fully Load

I recently went through a similar puzzle, but in .45ACP. And with a new to me S&W Model 22. I could not at first understand why the round failed to fully chamber, when they fed fine in my 1911 and plonked right into the case gage.

First thing, I scrubbed the cylinder well, and checked the measurements with a good caliper. SAAMI maximum or less.

Then I got serious and measured the chambers in the cylinder with pin gages. That's when I discovered S&W is .001"-.002" smaller than .473" SAAMI maximum. So, a cast lead bullet of .452 + .010 case thickness x 2 = .472". I am going to need to use jacketed bullets no larger than .451".

In your case however. Same guns, same components, same dies. Something has changed. A die came loose and has shifted. The Berry's bullets did not get swaged to the final size. Something has built up in the chamber(s). Both guns? Unlikely.

SAAMI maximum on 9mm Luger is .380. So say .356 + .010 x 2 = .376 Even if they were .358 and thicker cases, that is still right at SAAMI maximum. Kinda hard to think the bullet is wrong sized.

Try this. Roll some on a flat table. Look for anything to indicate that the bullets are not centered in the cases. See if you can see the imprint of the bullet on one side of the case and not the other. That would mean it is out of concentricity and actually fatter than you can measure with a caliper. You do not mention checking it in a case gage. But the chamber of the gun is also a gage. The solution to that is to have a case in every station and loosen the lock rings on the dies. Then when you run the shellplate up, it should center all the dies. Lock the lockrings at that point. Your rounds should now appear to be even all the way around. Crooked rounds may also explain the scraping you are seeing.

The Dillon folks describe this in several threads. A search might turn one up. Sorry for the long response. I was thinking the problem through.
rfwhatley
rfwhatley
41 posts
Joined December 2007

RE: 9mm Failing to Fully Load

For me the answer lay in "Brass - various types that I collect at the range". It seems I picked up several cases fired by 9mm Major. Major PF uses such high chamber pressures that the cartridge cases actually expand at the case head. (That is, near the rim.) Due to the need to hold the case in the shellplate, this is a position that the dies do not resize. Once the cartridge case goes past the 0.390" case head dimension, it will not chamber ever again. So there was a reason the 9mm Major boys were not picking up their brass... It's dead brass do to case head expansion.

In 40S&W it's common to pass the complete case through a Case Sizing Die (aka "bulge busters"), but 40 is a true Straight Wall Case. 45ACP, 40S&W, 32ACP, 38Super, and all the other US-designed cartridges are "straight wall" cartridges, and do NOT exhibit issues related to the tapered chamber. So your experience with these calibers won't help you at all with 9x19, 9x21 or 9x23.

9x19 Luger includes a slight taper, and being tapered, this type repair simply won't work. 9x19 Luger is subject to multiple case issues related to the tapered cartridge wall shape. The only appropriate pre-loading test is a good cartridge gauge.

Hope this helps.