9mm not chambering right

Melnibonean

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I've reloaded probably 10's of thousands of rounds, but this one has stumped me.

Around every 10 or so rounds (thereabouts), my Dillon 650 produces a 9mm round that won't chamber properly. I seems "too big" for the chamber as it won't go in all the way, and I have a ##### of a time getting it out once the slide closes (part way) over it, having to do a forceful mechanical eject to get it out.

I've measured the case of a round that won't chamber vs ones that do: they're all within 1 thou of each other. The seating depth as well. The bullets are Zero's 125 JHP and the cases are range pick up.

The only think I can think of is that the brass isn't being resized right to begin with. I find I have a hard time from time to time lowering the arm on the press (as if a case is stuck inside one of the 4 dies somewhere), and this, usually with some Hornady brass that I picked up recently.

So before I chalk it up to the brass, is there anything else I should be looking at?
 
Your barrel out of the gun is the bast case gauge. If the bullet is touching the rifling the barrel the same issue will arise, try seating 5-10 thou deeper.
 
You mention that you are using range brass. Are you having cases with "Glock Bulge" sticking? Or non-brass cases? Steel doesn't like to be resized and aluminum cases don't like to stay sized (Springy).
 
You mention that you are using range brass. Are you having cases with "Glock Bulge" sticking? Or non-brass cases? Steel doesn't like to be resized and aluminum cases don't like to stay sized (Springy).

My steel 45cal cases and 45acp/ 9mm aluminum cases reload just fine. Although they are being fed mainly to a glock and Norinco 1911's. The aluminum 45's feed fine in my tanfoglio though.

But I would guess glock buldge as well, lower the sizing die if it isn't already just barely touching the shell plate.
 
The problem is brass shot through a pretty loose chamber and the FL sizing dies don't size low enough on the brass to resize that extra little bulge on the base. I've got a tight chambered 9mm pistol and I've had to run the ammo through a Lee carbide Factory Crimp die which helped a lot (as a bonus, it sizes a bit lower than the FL die) but I still get the odd one in about 40 rounds with chambering issues. I ordered a 9mm and 45ACP Lee Undersized FL sizing dies that supposedly sizes the brass to factory dimensions.
 
What happens when you use good brass? This kind of thing is why picking up range brass of unknown quality isn't a good idea.
However, it'll be either sizing or length. Neither steel nor Al cases are reloadable.
 
Case gauge your ammo. Also if your brass was fired through an open gun prior that could affect it. roll size plus full length resize will bring it back into spec

What exactly is an "open gun"? do you mean an unsupported chamber, or an open bolt firearm? just never heard that term before
 
What exactly is an "open gun"? do you mean an unsupported chamber, or an open bolt firearm? just never heard that term before

I venture to guess it's a "9mm Major" Open Division IPSC gun. Major refers to power factor over 160 (regular 9mm is around 125-130) which requires to load the regular 9mm brass and bullet with enough powder to reach a velocity around 1300 fps. Not suitable for regular 9mm pistols but dimensionally the same. Hence the pressure and deformation of the brass above the regular expectations. :)


To OP: I had similar problem with Dillon 650, replaced the dies and "fail to chamber" rate dropped from 5-6% to 1-2%. The failed ones are mostly OK for Glock, but not so for CZ Shadow.

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Lee Factory Crimp Die is often suggested as a solution. If apparently resizes the bottom of the brass once the round is all loaded. I bought one, and all my loaded rounds fit my M&P9 perfectly now.
 
I had a similar problem arise, after years of no problems. So far as i can tell, it was caused by some makers now making their cases a bit thicker. When the bullet is seated it expands the case a bit and the result is a fat round that won't chamber well in some guns.

I installed a Lee factory crimp die in the last position of my Dillon and no more problems.
 
For reference I am just basing this opinion on my experience as a not very good IPSC shooter; I reload for myself and my wife who also shoots IPSC. So I have battled the trials and tribulations of high volume 9mm reloading. So after moving through some progressions of equipment, and 10's of K of reloads I will try a properly convey myself without sounding arrogant or belittle anyone as that is the last thing I intend to do. I want people to learn from my mistakes and errors. If I can save you hassle, than my error was not in complete waste.

From my position I have to buy "reliability & confidence" in the form of additional reloading equipment. I don't really care too much if I get a stoppage while on the clock in a match, but I prefer that my wife does not. As it makes me look like a D**** Bag to the other shooters.

** Equipment Options to nearly eliminate failure to chamber**

When I first had trouble with range brass I picked up a Magma Engineering "Case Master JR." it is a push through base resized. It is around $400; If you are a low volume shooter this is not a bad idea. It served me well, and I never had any problems with failure to chamber after running through that machine followed by a full length resize. The only drawback was it required serious elbow grease to run.
http://www.magmaengineering.com/case-master-jr-rimless-case-sizer/

The next option to ensure that you will have near 0% failure to chamber is a case pro 100. They are expensive, and have about a 14 month lead time currently. However they chew through brass. It rolls the brass between two plates, driving any bulge into the middle of the case where it can be ironed out by a full length resize die. This is currently what I am running. It can be a little bit finicky, but with the auto drive it runs a bit better that 1600 cases per hour.
http://www.casepro100.com

Lee Bulge Buster - Not available in 9mm
http://leeprecision.com/case-conditioning-tools/lee-bulge-buster-kit/

Lee FCD (Factory Crimp Die)
A good option for those on a budget. It will eliminate a couple of percent of failure to chamber. However it is not a base resizer.
http://leeprecision.com/reloading-dies/hand-gun-dies/lee-carbide-factory-crimp-die

Or you could just refer back to barrel gauging and live with having the occasional failure to chamber. If your life truly depends on your ammunition, you should not be using reloads anyways.

In regards to the people reloading steel and aluminum cases, I do not have any anecdotal evidence to dissuade them. Although from a metallurgical standpoint I do not know what the work hardening would do. I do not know if the risk is worth the reward.
 
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I had a similar problem arise, after years of no problems. So far as i can tell, it was caused by some makers now making their cases a bit thicker. When the bullet is seated it expands the case a bit and the result is a fat round that won't chamber well in some guns.

I installed a Lee factory crimp die in the last position of my Dillon and no more problems.

Me too and it cleared up most all of this problem.
 
Just ordered the Lee factory crimp die to start with and another FL resizing die from Dillon to replace the one on there now. I'll try them out and post an update.

Again, thank you to all for your advice.
 
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