Let's talk about crimping the autoloader 9mm

[Ironicaintit]

I don't know what my deal is with FC cases in 9mm then. I didn't measure them......but they were presumably once fired (got 'em from my doctor) and I could squeeze the bullet further into the case with two fingers.

 

[LiveLife]

Resize some cases and measure at the case mouth. What OD measurement are you getting? (Measure 3-4 times around the case to check out-of-round)

And how much are you flaring/expanding the case mouth?

 

[RainDodger]

Zero crimp. Just remove the belled case mouth and bring the case back flush with the bullet. No crimp. That's what you do when your chamber is designed so that the case head-spaces on the case mouth. It has worked perfectly fine for me for nearly 50 years of hand loading.

 

[Dudedog]

but the excessive crimping causes it to loosen back up?

To much crimp squeezes brass and bullet. Brass springs back, bullet does not (or not as much as the brass), so now it is loose, no case neck tension.

 

[preacherJohn]

Zero crimp. Just remove the belled case mouth and bring the case back flush with the bullet.

So what are you using to remove the bell, the bullet seating die, or a FCD?

 

[preacherJohn]

not all 9mm bullets are sized .355"

After I seen this I measured a few of the Rainier 155 CPHP's and I had some that were sub-355. I was a little surprised at .3545. I have a lot of these bullets too. When I have more time, I'll measure more to see what's going on. I'm trying to use them up, my wife's Ruger doesn't group well with them at all, but my Sig and 92FS does alright. Well, there are a few flyers, but most groups are within 2" @ 21' without a rest.

 

[preacherJohn]

Rainier 155 CPHP's

To set the record straight, there's a typo here; it should read 115 CPHP's.

 

[LiveLife]

I had one bad magazine. It was new and never used, but it didn't tilt the bullets up enough so they would go up the feed ramp of the barrel. When I released the slide, the bullet jammed on the feed ramp, and after I cleared it, I noticed the bullet was seated considerably lower in the case than what I set it at.

Make sure the magazine spring was not put in backwards. Check with other magazines that are tilting the bullets up to see how the spring is installed and magazine follower is angled the same.

If magazine spring is installed the same as other magazines, I would compare the feed lips to see if they are bent/smashed and not allowing the magazine follower to tilt up.

Can you post picture of magazines at the feed lips/followers?

not all 9mm bullets are sized .355"

After I seen this I measured a few of the Rainier 115 CPHP's and I had some that were sub-355. I was a little surprised at .3545. I have a lot of these bullets too.

That could be the source of your neck tension and significant bullet setback issue.

To verify accuracy of your calipers, get a $5 pin gage - https://www.zoro.com/vermont-gage-plug-gage-minus-0355-in-black-911235500/i/G0146955/

So what are you using to remove the bell, the bullet seating die, or a FCD?

I use the combination bullet seating and taper crimp die.

 

[RainDodger]

In answer to preacher John... sorry I took so long to answer... I only use the seating die to remove the case mouth bell.