.38sc Brass Bulge

[Jack_Aus]

Hey guys

After shooting service for a few years I have taken the plunge into ICORE.  I’ve managed to source a 627 and all the other gear in time for the upcoming regionals here in Brisbane. 

 

Ive settled on Short Colt with a 160gn Coated LRN with 2.8 of AP50 (W231 equivalent). Federal Small pistol primers, OAL 1.200 with a taper crimp, makes 125-130pf.

 

I noticed last night after loading a few hundred a bulge roughly 5mm up from the rim of the case? There are no other signs of over pressure presenting in the fired brass. Could it be a cylinder issue? Or maybe a pressure issue? 

 

Cheers

Jack 

[PatJones]

The whole case doesn't go into the resizing die, it has to stick out a bit so you can pull it back out. The shell holder is .125 inches deep, and on top of that there is a small radius on the edge of the resizing die. This causes a small bump in the area you're describing. Do the cartridges drop freely into the chambers?

[MikeBurgess]

10 hours ago, Jack_Aus said:

Hey guys

After shooting service for a few years I have taken the plunge into ICORE.  I’ve managed to source a 627 and all the other gear in time for the upcoming regionals here in Brisbane. 

 

Ive settled on Short Colt with a 160gn Coated LRN with 2.8 of AP50 (W231 equivalent). Federal Small pistol primers, OAL 1.200 with a taper crimp, makes 125-130pf.

 

I noticed last night after loading a few hundred a bulge roughly 5mm up from the rim of the case? There are no other signs of over pressure presenting in the fired brass. Could it be a cylinder issue? Or maybe a pressure issue? 

 

Cheers

Jack 

All of mine look like you describe, as Jack said do they drop in the chamber? if so don't worry about it, Half my brass is coming up on 20 loadings and has looked like that since loading 1.

[GMM50]

I just bought a new set of Lee dies made specifically for 38 Short Colt. 

I was mixing and matching 38 special and 9MM dies.  And that proved to be a problem.

[Jack_Aus]

Hey guys 

They all drop in fine. Just wanted to be sure I wasn’t having pressure issues. 

Thanks for the help. 

[Gomar83]

9 hours ago, GMM50 said:

I was mixing and matching 38 special and 9MM dies.  And that proved to be a problem.

 

What kind of problems were you having with the mixed and matched setup on the does? If you don’t mind me asking.

[pskys2]

I noticed the same thing with all of my 357's.  First thought it was the magnum ammo, which does make it worse.  Then I thought maybe I'd been too aggresive chamfering the cylinder in my m28.  But my 627 does it even with short colts even with the light loads.  

Doesn't cause any issues so ignore it.

[GMM50]

It all started about 10 years ago.  Shooting 38 super in a 627-4.

I used a 38 special sizing die, don't know seating die, and a 9MM taper crimp die. 

Used that set up for many years.

 

I then switched to 38 Short Colt but kept using the same die set. 

Found I was not resizing to proper dimension, shaving bullets during seating and crimp was just a mess.

Soft lead bullets shot OK.  But could be better.  Some bullets were tumbling.

 

I took everything apart and tried to mix and match to get 38 SC dialed in.  But I couldn't resize or flair to save my life.

 

Found Lee made 38 SC die set and bought from Midway.

This die set was made for 38SC case lengths.  Resizing , flaring, charging and seating.  Crimp is still in process cause of case length.

 

I now need to trim the brass to length.  This reloading setup can detect some long brass by feel and the flair is then BIG.

So i need to get case length under control.  Then flaring and crimping should be resolved.

 

Group sized at 20 yards came down from 5-6 inch group of 8 shots (original mixed up die set) to 2-3 inch groups (with these proper dies)

Using Clays and Bang and Clang Bullets 145g RN No Lube Groove Coated. 

 

I expect there's another inch or 2 to go.

Edited September 4, 2019 by GMM50

[Vincerama]

On 9/3/2019 at 8:26 AM, GMM50 said:

I just bought a new set of Lee dies made specifically for 38 Short Colt. 

I was mixing and matching 38 special and 9MM dies.  And that proved to be a problem.

 

I bought the same dies (but for .38 Long Colt, not Short, but same die set) and ... it's a mishmash of dies. I don't have them here, but as I recall some of the dies are .38 S&W dies?

So ... still a mix and match.

[jhgtyre]

I bought a Hornady 38 special size die and my bulged 38 Short Colt brass was cured.  

[Gomar83]

So what actually is the difference between the mixed and matched setup versus the correct Lee die set? I understand that the crimp die is different but what are the other differences?

[pskys2]

The sizing dies are the same, the only difference for the 38 SC vs 38 spcl are the bullet seating and crimp dies.

 

Most of us, especially with Progressive Presses;

1)  use a 38 Spcl/Mag Carbide sizing die the Dillon has a beveled mouth that facilitates better case insertion and is more prone to leaving a slight step at the base, most other brands size down a touch more but the step is still there.  The more pressure the loads the more pronounced.  I've experimented with using a 9mm sizing die, just in case I went with a 929, and it sized fine and fit the cylinder fine.

2) use 9mm powder drop tube, advantage is a bit tighter grip on the bullet

3) use 9mm bullet seating die, just due to the fact most of us have them, and with Dillons they swap easily into a preset die, a 38 spcl won't seat the bullet deep enough

4) use a 9mm crimp die, just due to the fact most of us have them, and with Dillons they swap easily into a preset die, a 38 spcl die won't reach the shorter SC length to work. 

With a Revolver it seems a good tight taper crimp helps with a fast reload and is less dependant on overall case length.  With too short of a case you don't get a good roll crimp and with too long of a case it can actually bulge the case and if enough cause issues.  The Taper Crimp just smooths things out despite length.

I've tried the roll crimp and the taper crimp on 38 SC and see no consistent differences in velocity or accuracy.

Also if you use a longer bullet, 160 grain, you need to make overall length no less than 1.170".  At less you will see the occasional bulge at the base due to tolerance stacks of bullet diameter and interior case diameter.