Ok folks,

I've noticed just a slight bulge in my finished pistol cartridges. It's barely measurable, but I can see it. The rounds headspace, chamber and shoot flawlessly, but I don't see any bulge in factory ammo. I've tried flaring case mouths both more and less, and it doesn't seem to make a difference. I can still see where the base of the bullet is seated in the case. I've measured my bullet diameters and even the ones that are dead on correct still show a small bulge. Am I doing something wrong? Is it just because the cases have been fired once? Please let me know what you think. As always Thank You!

That's pretty common. The sizing die sizes the brass a little undersize, and when you seat the bullet it expands it back out. Nothing to worry about.

What calibers is this happening with? I've noticed it more with tapered cases like 9mm, and even my 458 Lott.

9mm luger is where I notice it. My .45 cases look great. I was thinking maybe my dies were messed up. It makes sense to me now that you have explained it though. It never caused a malfunction, I'm just a bit anal about the finished cases looking good. Thanks!

Medic

If the rounds chamber and shoot ok you've done good.

If you want to eliminate the situation that you are finding in those loads, sometimes they come about when the bullet is started into the case by hand in a non vertical position.

Also something to get that will solve the problem and allow your reloads to come back to factory specs so that they can be shot in any handgun of that caliber is a Lee carbide factory crimp die sometimes referred to as a FCD. What it does is size the whole case as the crimp in being applied as there is a carbide sizing ring on the bottom of the die and it sizes the round going into the die and coming out of the die. It is also possible to remove the top of the die and with other Lee parts push a case all the way through the die to allow the die to size the last part of the case down by the head. If you shoot Glocks or pick up range brass they are good things to have and run about $17-20 per caliber. Glock chambers sometimes exceed SAAMI standards and have a hard time being resized in other dies with the problem area being down by the case head where the characteristics of the Glock chamber being more open can put the "Glock bulge" in the case.

I never ventured into the Lee components in the past but do so now. Great stuff.

Common. The 9mm cartridge has a taper to it. The carbide sizing die sizes the brass more than needed. The deeper the base of the bullet is into the case, the more bulge you will see.

Thanks guys!

Small nit, I've always heard what your referring to as a "Coke Bottle" (common with the 9mm), not a bulge.
"Bulge" normally refers to the case swelling at the base, over the feed ramp area (Google "Glock bulge")

quote:

Originally posted by Tailgunner:
Small nit, I've always heard what your referring to as a "Coke Bottle" (common with the 9mm), not a bulge.
"Bulge" normally refers to the case swelling at the base, over the feed ramp area (Google "Glock bulge")

Thanks for that, makes sense!