Originally Posted by AtownBcat
ok so I have one more question. ok no promises there will only be one...
If fire forming these cases was going to solve this problem, why are my cases that have been fired(the other 20%) not showing an improvement in the bulge area? Not being a smart A, just trying to figure out how a light charge is going to affect/effect the brass differently than a "normal" load...
and here are the current powders I have. If one of these will work I can get started tonight if not I will have to make a trip in the AM....
Sorry for the late reply.
The bulge will not improve by fireforming the brass, but it will give you positive headspace, instead of the current negative headspace you have on your brass.
The reason you use a light charge is so that the case isn't stretched in the belt area, a light charge allows the entire case to move in the chamber when max pressure is reached, blowing the shoulder forward without the rear of the case being stretched to the bolt face. I have used this method for many years, and believe me, it works just as I state here. NO CASE STRETCHING OR BULGES OCCUR!
This will give you a new starting point for that brass lot.
A normal pressure load causes the case walls to grip the chamber tightly, not allowing any case movement, and due to headspace, the case walls just ahead of the web, the solid portion of the case, stretches backwards until firm contact is made with the bolt face, this is what is causing the bulging in your rifle cases.
Technically, a belted case headspacing on the belt is correct in all aspects, but chamber dimensions in the shoulder to belt measurement are not held to a tight tolerance, neither are case head to shoulder measurements, this can compound, making things even worse.
Of all the powders you list, only Benchmark would be suitable with light bullets, you really need to use a fast pistol/shotgun powder with pumpkin or potato to do the job correctly.