Cases bulging...

[Bimmer]

Hi all,

Several of my reloaded .38 Special cartridges look like the one on the left, here:



I'm reloading "once-fired" nickel brass, so I don't know their provenance, or whether the were already bulged.

I don't know if I screwed it up by not sizing it enough, as this site says:

http://www.massreloading.com/straigh..._resizing.html


Thoughts?

[JM7.7x58]

Pull your boolit, size the case again, if the bulge is gone, then it’s not how your sizing, it’s how your crimping.
JM

P.s. I vote for trimming down your brass. It will reduce your case capacity, and get that 3 grains of Trailboss burning right.

[Sig556r]

Hi all,

Several of my reloaded .38 Special cartridges look like the one on the left, here:



I'm reloading "once-fired" nickel brass, so I don't know their provenance, or whether the were already bulged.

I don't know if I screwed it up by not sizing it enough, as this site says:

http://www.massreloading.com/straigh..._resizing.html


Thoughts?

That's a bulge from high pressure or unsupported chamber.
Pull the bullet out & resize, if it straighten well & good, if not, the sizer is not reaching the bulged spot.
Recheck after seating/crimping, you might be crushing down the brass a tad.

[Land Owner]

You are causing the bulge during crimping as you indicate that case hasn't yet been fired. Pull the bullet. Resize the case. Seat the bullet in a separate operation from crimping. Do not crimp "so hard". All you need is a nudge. Crimping presses DOWN on the case. Too much crimping bulges the case below the die body - as you have discovered.

Most of us never trim our handgun brass. It isn't subjected to the same stress (~1/3) of a bottle necked rifle cartridge. Brass elongation in a handgun is not as pronounced.

Let us know when you find the solution.

[JonB_in_Glencoe]

Another thought, the bulged brass in your photo has 2 cantalure grooves, meaning it's WC brass, which doesn't have the tapered wall thickness that standard brass has, so it's more likely to bulge if improperly crimped.

Are all the bulged cases, the WC style ?

[Taterhead]

Another possible culprit: I've had some decades old brass that was so thin that it wasn't sufficiently sturdy to lift the powder measure without buckling (progressivewith RCBS case-activated Uniflow). Took me forever to go back through the steps to find that. They look EXACTLY like the photo.

[reddog81]

In your other post I mentioned that over-crimping can result in problems. This is one of the problems that can happen. The brass gives way and distorts before the brass digs into the bullet.

Your Trail Boss loads need more pressure/powder to operate correctly. Changing the primer, seating a smidgen deeper, crimping heavier aren't going to do the trick...

Trying to size brass in a steel sizing die without lubricant can cause similar issues because it just pushes some of the brass downward rather than sizing it correct.

[country gent]

Never seen a bulge caused by crimping that far down the case its usually just below the crimp or bullet base. I would check a couple things 1) is the sizer die down touching the shell holder? if not you may only be sizing to that height and leaving the rest unsized. 2) the size shape and depth of the expander in the die set. I had a set of 45 dies that sized so small when expanded and a bullet seated the rounds had a definite coke bottle look to them.
Even with carbide dies I apply a very thin coat of sizing lube, it eases and smooths the sizing operation making for more consistent sizing. If you have a trimmer use it on a few cases cut very lightly and see if the case mouths are square.
Is this new brass or fired ( possibly in another firearm?)

[megasupermagnum]

I don't think it would be possible to have an over pressure round bulge like that, not in just one spot. If it was the chamber, you would not be able to extract that round. That is most certainly caused during reloading. Probably not the sizer, more than likely either during the expanding or crimping. It's obviously a weak thin spot, don't use those for full power ammo.

[Bazoo]

When are you noticing this bulge? Since the case shown still has the primer, we can only assume it's after firing? If so it's a sloppy / bulged chamber. During the reloading cycle, I can think of nothing that would cause that.


As a side note, I trim all my pistol brass that gets roll crimped for consistency, such as 38 special.

[6bg6ga]

I don't know how one could possible screw full length resizing to cause what is being shown in the picture on the left. The article says basically different presses different requirements if i sped thru it correctly. Full length resizing is basic you size down as far as you can get depending on the caliber without bottoming out the die on the case holder. What else is there? I use carbide die sets so no lube needed.

[Land Owner]

Nope. I didn't read it so you got me. There is only one way, of which I am aware, that a case could be bulged like that - out of battery firing - as it is neither a resized case with a spent primer still in its rear end nor a crimped round.

Here's a shotgun shell that my son had the discomfort to fire out of battery and it expanded every micro-inch of the base and brass that was exposed:

[mdi]

FWIW; in my short time reloading (started 1969) I have never seen nor heard of an "unsupported chamber" on a revolver, especially 38 Special. Here's a fool proof method the locate the problem; start with a known good case, measure the body. Load the case as usual, measuring the case after each step; measure after sizing, after, flaring, priming, bullet seating and crimping. This will tell you when the bulge happens and then you can correct the problem.

[JonB_in_Glencoe]

The PHOTO in this thread came from that ARTICLE. Did anyone bother to read the article linked in his first post? Something is not right somewhere.

I plead Guilty, I didn't read the article, I didn't realize the Photo was from the article
So that leaves my previous comment a moot point.
I would need more info and maybe a photo of the OP's actual cases with the bulge issue, to offer anything new.

[Bazoo]

I overlooked that there was an article. Oops.

Revolvers ain't the only firearms that chamber 38 special. Could be anything from a martini to a S&W 52.

[country gent]

I to am guilty of not reading the article.

[M-Tecs]

I did read the article and the author makes claims like this"

"Notice the prominent bulge near the bottom of the improperly resized case. This bulge developed because of repeated incomplete resizings of the case. Running the already-bulged cases though a properly set resizing die does not fix the problem; it actually makes it worse. Instead of removing the bulge, it pushes it farther down the case and expands it to the point where some of the cases will not even chamber. "

I fully admit it have never worked with 38 special case that have been repeatedly incompletely sized. I have resized 38 brass fired in a Martini Cadet with a way oversized chamber and I never had a problem resizing them to fit a standard chamber. Frankly I don't find his claims credible.

[mdi]

Well, I gotta admit I missed the article too. But in light of checking it out and the cases in the pic weren't the OP's and could be anything, even bulged on purpose for the article, this whole thread is worthless. Good, informative answers, but answers to a questionable question...

[Bimmer]

Thanks, guys...

Right, that's not one of my cases, but some of my loaded cartridges look like that.

I'm looking through the "once-fired" brass that I bought, and a bunch of them look like this.

These are cases that I have NOT fired through my gun or with my loads.


I screwed my sizing die down further (now it touches the shellplate) and backed off the crimp die 1/6th of a turn, and the problem seems to be reduced... The real test will be whether they chamber easily.

[JonB_in_Glencoe]

Did you try to put one of the bulged fired empty cases into your gun's chamber ?