Bulging cases...

[Mr_Gun_Guy]

I’m reloading some .44 magnums with 300 grain XTPs and I’m seeing about half (26 out of 50) have these bulges right at the point where the bottom of the bullet is. Not sure why this is but they easily fit in the cylinder of a Colt Anaconda. One thing I did notice is that the tighter the round was in going up into the die the more likely it was to not have the bulge. Anyone have any thoughts on this?

 

[mrawesome22-250]

It's called the coke bottle effect from using carbide dies that only size using an insert that can only size to one dimension that is cylindrical.

Tapered steel dies will eliminate this and the cases will have a better fit in the chamber, but they require lube.

 

[AJC1]

You found the yield strength of the case wall. The combined resistance of seating is higher than deforming one side

 

[Mr_Gun_Guy]

Thanks, guys. I thought it was something involving the wall thickness (strength) of the casing. They fit in the cylinder just fine and come out without using the ejector rod so I think I’m good to go. They just look ugly.

 

[Mr_Gun_Guy]

That wasn’t the problem here, I’m sure. In fact the bullets that were deepest set into the case were more likely to have the problem.

 

[NMexJim]

Mic your loaded round and compare. I’ loaded .44, .357 and 9 mm that looked the same as yours (I don’t overcrimp by any measure) and shot very well. A case can be squeezed down pretty far in the FL die. Your expander plug may not be getting down quite far enough.


The

 

[NMexJim]

You found the yield strength of the case wall. The combined resistance of seating is higher than deforming one side

Is the “bulge just on one side or all around?

 

[Lennyjoe]

Could also be bullet alignment when seating. Maybe flare the case mouth just a bit more so you get a little straighter bullet alignment before seating the bullet.

 

[film495]

does the bulge follow the bullet down as it is seated? like if you only seat it half way and then check is the bulge there and it moves down as the bullet is seated? how much is the bullet expanding the case? does it look lke that before crimping?

 

[Walkalong]

Not unusual, it means your sizer is doing the job very well, better than needed actually, but the reason die sets have expanders. Sizers need to be tight enough to size the thinnest cases down enough to get proper neck tension, so that means the thicker cases get sized more than needed. And of course we have manufacturing tolerances so not all sizers will be exactly the same. After sizing our expander brings the case opening back to the right ID, or at least it should.

You can try different sizers that may be a better fit to your brass, but it's an expensive game to play and is luck of the draw.

If the bulge is equal all the way around that is a good sign. If not, it may be brass that is thinner on one side, or bullets not being seated as straight as possible, but you may find they shoot great anyway.

A Magtech 125 Gr JHP in .357 Mag with a nice medium roll crimp into the canellure.

 

[Mr_Gun_Guy]

The bulge is all the way around and moves downward as the bullet is seated.

I shot a round of them and they were fine. In fact, the cases had lost their bulges so I feel like I could reload them again. I was doubtful of that at first.

 

[Lennyjoe]

If it’s symmetrical then you’re good to go

 

[NMexJim]

The bulge is all the way around and moves downward as the bullet is seated.

I shot a round of them and they were fine. In fact, the cases had lost their bulges so I feel like I could reload them again. I was doubtful of that at first.

Good to go!

 

[9mmepiphany]

If it’s symmetrical then you’re good to go

Yup, means the bullet was started straight.

What some folks have done, for straight wall cases, is use the Redding Carbide Dual Ring Sizing die. One ring sizes the body and one, further in the die, sizes the mouth/neck area for proper neck tension

 

[Walkalong]

The bulge is all the way around and moves downward as the bullet is seated.

I shot a round of them and they were fine. In fact, the cases had lost their bulges so I feel like I could reload them again. I was doubtful of that at first.

You're definitely good to go.

 

[Erief0g]

The bulge is all the way around and moves downward as the bullet is seated.

I shot a round of them and they were fine. In fact, the cases had lost their bulges so I feel like I could reload them again. I was doubtful of that at first.

I think I smell burnt powder!