g26westgate
g26westgate
21 posts
Joined February 2014

bulged 40 cases

What am I doing wrong.

I am loading 40 S&W through my SDB and I am getting loaded ammo that do not fit my chamber.

I use assorted brass that I can find on the range, run it through as normal on the press and some of them appear to have a bulge at the rear end that when I place the loaded ammo through a case gage, some of them wont go through. Is there a way to fix these for me to be able to use them still?
lcb
lcb
277 posts
Joined September 2007

RE: bulged 40 cases

If you are collecting range brass (AKA: Other 40S&W than what just went through your firearm), then those cases may not work in your firearm.

Some firearms result in bulging of the 40S&W case. Full length resize will not squeeze the bottom of the case back to fit in a case gauge.  If the case was shot in your firearm then it will most likely word fine after reloading, even if it does not fit through a case gauge. Glocks are know for causing 40S&W bulging. There are a few other brands.

I am not aware of a passthrough resizing die for the SDB.  There are several made for 'standard' size dies.  The passthrough dies push the whole case through the die.  No need to case gauge after running through a pass through die.  But I would inspect every case for cracks, etc.

I do not have a pass through die, so my 40S&W process is: 1) clean the cases, 2) lube the cases - some will sat lubing 40S&W is not required - but I do to lower on the loader and case, 3) full length resize and deprime, 4) check every case in a case gauge.  The ones that do not fit are put aside.  I have two toolheads one for the above and one for full reloading below.  Later I reload only cases that fit in case gauge.    Case that do not fit case gauge get recycled (trash recycle container).   I get so few of them I rather discard a stressed out of spec case then try to try and reclaim the range brass.  Safer that way.
dillon
Administrator
dillon
2,866 posts
Joined July 2007

RE: bulged 40 cases

First reply was largely correct.  40S&W(short&weak) does have a bulging problem and some brass and gun combos are worse for it.

If the press is older, a new friction plate might help (13721), you can call us for that.

Lubing the cases might help. If not you can chuck the bad ones or use a roll sizer press or a push thru die on a single stage.

g26westgate
g26westgate
21 posts
Joined February 2014

RE: bulged 40 cases

Dillon,

I need help still on this.

Here is what I have found.

I have employed a single stage press as a pre-sizer to push through the empty cartridge to resize it in full.

While empty I check it by dropping it into the case gauge and it plunks like a charm.

I start reloading it through my SDB press, using lead projectiles.

once loaded, I check the crimp and its at 0.420, which sounds tolerable and within suggested range.

Case gauge, it now hangs just a tad with the rim not flush anymore. I begin to think, what has happened when the shell previously fit the gauge and not that it is loaded, it does not and yet my crimp is correct.

This is driving me crazy. I then put the live ammo through the separate resizer and gauge it once more, it still is not flush by just about 1mm. I then force it in and it does go in. But what I found when I took the ammo out of the gauge, one side of my lead projectile has been shaved by the case gauge and it became shiny silver. After several pushing into the gauge, exposing one side of the projectile silver lead, it now fits well.

Chamber check it is now flawless.

I measure my projectiles and they are all 0.401 and my pistol has chewed these type before flawlessly as long as they fit my gauge.

I look through the gauge and there are no sharp edges in there. it is as smooth as.

So, what am I doing wrong? Any ideas I am open to on how to fix this.
dillon
Administrator
dillon
2,866 posts
Joined July 2007

RE: bulged 40 cases

Size and deprime a handful of cases. Gage these cases, see if they all gage properly. If the case rim fails to enter the gage, reverse the case and see if the rim enters the gage. If the rim fails to enter the gage, then a burr or deformation to the rim is the culprit, which won't affect usability.

 Load the cases that passed the initial check, then gage again. Please let us know what you find.

g26westgate
g26westgate
21 posts
Joined February 2014

RE: bulged 40 cases

Ok, I've done the checks and here is what I found:

deprimed cases only on stage 1. Gauged the cases and they all passed through the case gauge like a charm.

I reversed the cases and they too went in smoothly.

loaded rounds. Most went well but had a couple that failed the gauge with the rim just ever slightly sticking out.

I reverse the live ammo with the rim going into the case gauge and it drops in very well. Projectiles? but they measured .401 on the caliper.

Having said that, I can force push it in the case gauge and it goes in but sticks and have to force it out poking it from the other side.

I do this a few times and the results are weird, something I havent seen before.

Bad ammo number 1
One of the side of the lead projectile just above the rim of the cartridge appears to have scratched and exposed the silver lead, shaving some fine lead off.

Once this has happened, the bad ammo now plunks well into the gauge.

Bad ammo 2
Doing the same above, but cannot force it into the case gauge so it remains as is.

reverse with rim first into the gauge and it goes in slightly some resistance but goes in.

Very confused...
Jon Divishek
Jon Divishek
4 posts
Joined December 2013

RE: bulged 40 cases

I ran into the same thing with my 1911 45acp when some range brass got mixed in with my fired brass. Pistols with an unsupported chamber bulge the head of the brass. No resizing dies will remove it. Order a Lee buldge buster and run all you cases through before reloading, They will then drop into your case gage just fine.
dillon
Administrator
dillon
2,866 posts
Joined July 2007

RE: bulged 40 cases

How much do you flare the case mouths?  Cases should be flared so the mouth is at least .10" larger than a sized, unflared case.
g26westgate
g26westgate
21 posts
Joined February 2014

RE: bulged 40 cases

I did not think I could adjust a flare on a 40 s&w SDB.

The flare on my cases are almost unnoticeable.

Having said that, the powder die is fully in and there is no further way to turn it further to increase the flare. I'd say its at its maximum and yet it barely flares.

I could see that the case hardly gets on to the section where the powder funnel begins to widen out. It just touches that section I'd say just at the very tip and just a tad.
dillon
Administrator
dillon
2,866 posts
Joined July 2007

RE: bulged 40 cases

Be sure you have a W powder funnel inside the powder die. Pull the handle down, be sure the powder die does not contact the top of the shellplate. As long as it doesn't, there is room to increase the case mouth flaring. Turn the powder die down in 1/4 increments, then test.
Stratoax
Stratoax
1 post
Joined December 2017

RE: bulged 40 cases

Because early Glock's cause the bulge you will need to run all range brass through this.
https://leeprecision.com/case-conditioning-tools/lee-bulge-buster-kit/