Bulging cases

[tboy]

Is this common with open bolt guns? I'm trying to process thousands of 9MM casings and find about 1/4 will not fit in my barrel (using a 226 barrel for gauge).

Not fun after loading a thousand rounds to find many do not chamber. My current process has me depriming in my Hornady multiple stage press, gauging, and then rerunning in a RCBS single press. This takes longer but that is the only solution I have.

 

[D-boy]

It happens to me and I have heard it is normal but I am no expert.

 

[ogree]

Bulged brass for a subgun is normal.
If the sizing die is adjusted down far enough in the press, you should not have any problems with the re-sized brass being bulged.
You may have to try another sizing die.

 

[tboy]

The Hornady press does not allow the proper sizing so I use the single stage which fixes the problem.

Thanks for the confirmation!

 

[ogree]

Bummer.....I didn't know that about the Hornady presses.

 

[Nate7667]

What Hornady press do you have?
Is it a progessive?
If so, can you set up you stations to use a Lee Factory Crimp Die for the final step?

 

[tboy]

What Hornady press do you have?
Is it a progessive?
If so, can you set up you stations to use a Lee Factory Crimp Die for the final step?

I have done that but the crimp doesn't help with the bulges at the bottom of the case. The Hornady progressive uses a plate which doesn't allow for 100% removal of the bulges and if you tighten down too much, the die pops out or plate has issues. Keep in mind, you could get it to work a few times but when processing thousands of cases, problems arise.

 

[Nate7667]

Gotcha
Im not familiar with the Hornady presses. Thats why i asked.

Im kinda wondering why i dont have this problem. I have reloaded well over 5k rounds of all kinds of brass fired from my M11/9. I have yet to have a problem with a round not going into the chamber. I am using a Lee Pro 1000 with Lee dies. I did buy but the FLC die, but not used it yet.
.....probably just hosed myself on the next batch of ammo

 

[fingaz]

Gotcha
Im not familiar with the Hornady presses. Thats why i asked.

Im kinda wondering why i dont have this problem. I have reloaded well over 5k rounds of all kinds of brass fired from my M11/9. I have yet to have a problem with a round not going into the chamber. I am using a Lee Pro 1000 with Lee dies. I did buy but the FLC die, but not used it yet.
.....probably just hosed myself on the next batch of ammo

Without knowing it you have another part of the solution at hand. Many times I have seen folks recommend the Lee sizing die for this very issue. The Lee die gets lower on the case with the carbide sizing donut, helping eliminate the bulge.

 

[Nate7667]

Good to know.
I have no other brand of 9mm dies to compare to.

 

[medphys]

Without knowing it you have another part of the solution at hand. Many times I have seen folks recommend the Lee sizing die for this very issue. The Lee die gets lower on the case with the carbide sizing donut, helping eliminate the bulge.

I have a Lee single stage press with both Lee and RCBS dies and have never had problems with cases not chambering.

 

[dbailey]

Is this common with open bolt guns? I'm trying to process thousands of 9MM casings and find about 1/4 will not fit in my barrel (using a 226 barrel for gauge).

I've always used dillon case guages to validate my loaded ammo, never really looked at how the loaded round is represented in the barrel. I tired and noticed that a 9mm loaded round will stick out of the barrel about 1/4 (I didnt pressure/force the round into the chamber, just dropped it in). I assume this is correct in the mac 10?

 

[shawnr1]

My cases still have small bulges on them after reloading. I do not have any problems with my rounds chambering my Max-11DF.

 

[trey504]

I reload my max11 brass with RCBS dies, and they work fine in my Glock,Ruger, and S&W.

 

[Shattered]

Get a roll sizer... no more bulging problems.

I just borrowed my buddies Case Pro. Now I have to build one... the company is toes up or so I've been told.

 

[TrippHammer]

bulging cases is usually caused by improper case lenght.
trimming your cases on a regular basis will prevent this, however a roller sizer will fix the problem.
small base dies work some, but the shell plates on most progressive loaders
prevents the dies from going all the way down to the rim.

i hate trimming cases but 99% of bulging brass cases is caused by the lack of trimming.

I reload ten of thousands of rounds primarily for my personal submachine guns & I dont catch everyone, but some calibers seem to lenghthen more than others.
All the open bolt submachine guns work on the principle of pre-ignition.
the .9mm UZI & Mac style submachine guns are notorioius for bulging cases because the round actually fires before the bullet face has fully seated in the chamber.

 

[bwsmg]

http://magmaengineering.com/products/case-master-jr-rimless-case-sizer

http://www.casepro100.com/index.html

 

[r]

tboy
I run both open bolt and closed bolt 9mm guns. something I learned a long time ago. Some open bolt guns (like SW76/MK760) leave about 1/3 of the rear of the case unsupported (sticking out of the chamber during battery). If you use commercial 9mm that has been reloaded and shot numerous times and load it too hot you will have case head separations. Believe me when I tell you blowing the lip off a MK760 bolt will put you immediately out of business. A closed bolt (like an MP5) supports the complete case and such problem do not exist. I have found that for me to mix fired 9mm thru either gun I have gone to using only military WCC brass with the thicker walls. Once I bring in a fired load I resize on a dedicated single stage with a carbide sizer die and a milled down shell holder to reach as far down the case as #1 (resizing station) on the Dillon 650. This also gives the machine a better feel on seating primers. This does take a lot of work up front to swage, ream and counter sink the 9mm pockets, but on a progressive press to not hang up that is what is required. also if you are going to do lots (1000s) of rounds a taper die and a chamber gauge are a must.