Jump to content
Brian Enos's Forums... Maku mozo!

bottom case bulging using AET super 38 need help


Flight

Recommended Posts

New open gun built by a gunsmith

AET barrel super 38

Load: 124 grains with 7.8 VV 3n37. Factor 165

My once fired case are all bulging at the bottom of the case. Checked the chamber and as we all know its got fluting and the bottom/outer part of the chamber is kinda beveled. The case itself is good except for the bottom or outer part of the chamber where the bevel is, that where the bulging in the case occurs. Is this normal with the aet in super 38 because in aet 40cal standard I dont see this kind of problem.

Couldnt go lower in my load since my factor is 165 already. So what to do? Need you help here.

I'll be getting my camera soon I'll post pics of the brass asap.

Link to comment
Share on other sites

Not sure how bad your bulging is but I to started a thread because of my bulding and it seems to be pretty comen. After you size and load them will they fit in the chanmber gauge or your chamber ? If so I would keep shooting it. I'm on a few reloadings with no problems. Also I'm useing 8grs of VV N350 and have loaded some vv 3n37 at 7.0grs-8.2grs with the same bulging.

Link to comment
Share on other sites

I don't know about AET barrels, but bulging is quite common in non supported barrels and a little is expected even in supported barrels. 38 super is a high pressure load, so some bulging (shouldn't be to extreme though!) is acceptable. After all, that's why we re-size brass (at least one reason why). What kind of brass are you using? Some brass has a weaker web than other types. Are you using 38 super +P brass? Your load is well within acceptable range as far as powder goes, but what is the OAL? The slightest difference in OAL in an already high pressure load can lead to drastic pressure changes, causing the bulge.

Link to comment
Share on other sites

Werewolf- I think were on the same boat here. What I did on the range today was I brought 20 brass and started shooting and reloading the same brass while inspecting on pressure signs. It would bulge at the bottom like a wedding ring but once resized it came back to form. I ended my session with 12 reloads with the same brass. So far so good but I'm just not comfortable or maybe not used to this bulging on the brass but made 12 reloads til it was late in the afternoon. I'll probably load the same brass 3-4 more times and I'll retire them.

Anybody experience this please chime in.

Link to comment
Share on other sites

Werewolf- I think were on the same boat here. What I did on the range today was I brought 20 brass and started shooting and reloading the same brass while inspecting on pressure signs. It would bulge at the bottom like a wedding ring but once resized it came back to form. I ended my session with 12 reloads with the same brass. So far so good but I'm just not comfortable or maybe not used to this bulging on the brass but made 12 reloads til it was late in the afternoon. I'll probably load the same brass 3-4 more times and I'll retire them.

Anybody experience this please chime in.

Sounds just like my story. I always knew it be bad and I have just got use to it now. I have only been shooting Open for a few months now and don't know nearly know what some of the others on hear do. My pf with N350 is 175 and other than looks this bulging has never cause me any trouble. I am shooting supercomp and sounds like your shooting super but if your on that many reloading I would say your buldge is nothing to worry about. On the topic I started, a fourm member posted a picture of a case he cut of his bulged cases that had been shot many times to show that the case thickness was still good as well. Search it out and read up on it.

Happy shooting,

David

Edited by werewolf45auto
Link to comment
Share on other sites

pics might be helpful so we can see just how much bulge you're talking about. the question is how much of a bulge do you see. if the sizing die is removing all of the bulge then you might not have a problem. on the other hand, if the bulge is big enough that it is causing cracks in the metal, that's a potential problem. see http://www.38super.net/Pages/Brass.html near the bottom of the page for examples.

werewolf45 - you might be referring to an excellent photograph by G-ManBart. a search should find it. also, that photo can be found at http://www.38super.net/Pages/Brass.html, near the bottom of the page, figure 2.

Link to comment
Share on other sites

All of the Super/Supercomps I've seen will bulge the case a little bit. It usually just looks like one side has a bit of a guppy belly to it. There shouldn't be any sharp edges to the bulge...it's just a gradual taper on one side of the case. If they resize properly and fit the chamber, you're probably fine. Here's a link to a site where the pics of the sectioned cases are posted...good reading:

http://www.38super.net/Pages/Brass.html

Edit to add: Superdude typed faster! LOL.....

Edited by G-ManBart
Link to comment
Share on other sites

All of the Super/Supercomps I've seen will bulge the case a little bit. It usually just looks like one side has a bit of a guppy belly to it. There shouldn't be any sharp edges to the bulge...it's just a gradual taper on one side of the case. If they resize properly and fit the chamber, you're probably fine. Here's a link to a site where the pics of the sectioned cases are posted...good reading:

http://www.38super.net/Pages/Brass.html

Edit to add: Superdude typed faster! LOL.....

Bart,

This is the exact problem that Jerry B was having with his new Open gun. Hellacious problems with jamming. Looking at the chamber of his barrel it was easy to see that the bottom was cut different. It was not touched by the smith who put it together for him as it had the fluted chamber. He was told by the good folks who made the barrel that he was loading too hot even though he chronoed his loads at 172 PF. He had the gun rebarreled (KKM) and a new slide fitted about two months ago. No problems since.

CYa,

Pat

PS Hope you are having a safe and comfortable journey. :cheers:

Link to comment
Share on other sites

All of the Super/Supercomps I've seen will bulge the case a little bit. It usually just looks like one side has a bit of a guppy belly to it. There shouldn't be any sharp edges to the bulge...it's just a gradual taper on one side of the case. If they resize properly and fit the chamber, you're probably fine. Here's a link to a site where the pics of the sectioned cases are posted...good reading:

http://www.38super.net/Pages/Brass.html

Edit to add: Superdude typed faster! LOL.....

Bart,

This is the exact problem that Jerry B was having with his new Open gun. Hellacious problems with jamming. Looking at the chamber of his barrel it was easy to see that the bottom was cut different. It was not touched by the smith who put it together for him as it had the fluted chamber. He was told by the good folks who made the barrel that he was loading too hot even though he chronoed his loads at 172 PF. He had the gun rebarreled (KKM) and a new slide fitted about two months ago. No problems since.

CYa,

Pat

PS Hope you are having a safe and comfortable journey. :cheers:

Hey Pat,

Yeah, I talked to Jerry about it. It seems that was a bit different than this poster since Jerry's wasn't running and the OP's is. I wish I'd known about it at the time, taken a look at the barrel and then called Mike up to see. All of my Super/sc barrels( Bar-Sto, KKM and Schuemann) put a bulge in the brass. They're all pretty similar actually and the brass seems to last a long time, but it's a fairly minor bulge. I'm curious to see some pics of the OP's brass.

In fact, I remember NM3gnr bringing me some once-fired brass out of his new gun and asking me if the bulge was unusual. I grabbed some out of my guns and we compared...essentially identical.

Drive is going well and we've only got 300mi to go tommorrow! R,

Link to comment
Share on other sites

My aet 40 cal brass is bulging just like what you all have described. I have had some types of brass blow the case heads off!! So now i just load the same brass 3-4 times and then i get rid of it. My load is lower than p pres's load but he is using a sti barrel.

Link to comment
Share on other sites

  • 2 years later...

I put a AET barrel in one of my Caspian guns after I noticed the cases were bulging I contacted scheumann they said the barrel is designed like that to let you know the pressure is to high...... I was using 10.7 grn of 3n38 which is not suppose to create that much pressure. Long story short if you shoot a AET barrel use that brass in that gun only cause it generally won't run in other barrels once it bulges. Stick to an svi barrel...

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...