new brass -vs- once fired

[Grassman]

I am working on some 40 cal. S&W loads. This is my first attempt a handgun loads, so mistakes could be at play here. I started with some once fired brass, which after I finally got my taper crimp dies set(that was a whole other problem setting those up too) the first 50 came out perfect. Then the next 50 were going to be new brass. Dies set the same, but the ones with new brass came out with a slight bulge about half way down the brass, where as the once fired came out perfect. Why is this? Is there something that I need to be doing to the new brass? It's a very slight bulge, more cosmetic than anything, but very unsightly. Any thoughts? Thanks

 

[highlander 5]

Is it a crease or a bulge? if it is a crease on the circumference of the case it may be that the new brass has thicker wall than the once fired brass. Next question is are you using jacketed or cast bullets. Cast bullets are usually have a .001-.002 bigger diameter which may be causing the crease/bulge.

 

[Grassman]

A slight bulge, jacketed bullets....

 

[Grassman]

My first thought was too much crimp........ causing it to catch the lip of the case on the brass, resulting in a crimp in the case? I don't know?

 

[Grassman]

After further inspection it is a slight bulge, rather than a crease.

 

[Grassman]

It only does it with new brass, I went back with some once fired, and they came out perfect again.......I'm stumped?

 

[Mt Shooter]

picture?

 

[Grassman]

I don't have any pics, but it is a slight bulge about half way down the brass, going around the case. It's very small, prolly won't matter in firing.

 

[armoredman]

Did you full length resize your new brass? If not, it was slightly undersize, I'll bet - looks kinda like an old glass Coke bottle now, loaded, doesn't it? If so, nothing to worry about.

 

[Grassman]

Well, I chamfered it and the new brass came out great. Is it too uneven? Why did this help?

 

[bullseye308]

Was it all the same headstamp? I have had/seen brass bulge in my 9mm using jacket bullets before. It looks like you can see the imprint of the bullet through the case right? Check it in your barrel with the barrel removed from the pistol and see if it chambers the same as one without the bulge. If it does, don't worry about it and shoot it. If it doesn't chamber, you may have to try the Lee Factory Crimp Die and see if it will bring them down enough to chamber. That or pull them apart and wait for a better answer than mine.

 

[Grassman]

For what ever reason, if you chamfer em, they come out looking great. This is brand new winchester brass.

 

[qajaq59]

Try measuring the length of that new brass.

 

[243winxb]

The slight bulge you are seeing is normal. A few things cause it. The wall thickness is on the large side. Another reason is that Full length sizing dies size down much more than needed. This is done so that all brass with different wall thickness can be reloaded. The expander ball only goes into the case so far to form the correct inside diameter for the bullet. The slight bulge will not not hurt a thing. If the bullets are the correct diameter and the rounds chamber i see no problem.

 

[Walkalong]

The chamfering helped because it helped the bullets seat better/straighter. That said, a little "buldge" is normal. It all depends on the brass, how tight your sizer is, how big the chamber it was fired in/the pressure it was fired at, wall thickness like 243winxb posted, etc. All these things like the buldge you are asking about is part of the learning curve. Assuming it is a small one, no worries.

 

[243winxb]

If the bulge is only on one side of the case, the bullet is not being seated straight. This happens if the seating stem does not fit the bullets nose. Or maybe your did not bell the case mouth enough. Some times it just takes a little more effort on your part to sit the bullet on the case straighter.

Well, I chamfered it and the new brass came out great. Is it too uneven? Why did this help?

This would help the bullet start in a straighter alignment.

 

[243winxb]

I finally got my taper crimp dies set(that was a whole other problem setting those up too)

If there is a large difference in brass length between lots, you may have to adjust your taper crimp die. You only need one taper crimp die, how many are you using, sounds like more than one??? I adjust my RCBS taper crimp die by putting a loaded round into the ram/shell holder. Run the ram/round all the way up. Now screw the taper crimp die down by hand as hard as you can. Your setting the crimp as you do this. I feel thats all thats needed and you will not over crimp.