Author Topic: PPB Expansion (Read 1084 times)

jpuke · « **on:** February 15, 2005, 08:44:56 AM »

I went out the other day to try to test the expansion of my load for a 530 gr PPB out of my Marlin 1895. I used water-soaked phone books for the test and fired into them from 25 yards away. The ONE bullet (of the five I shot) that I was able to recover sailed through the 20 inches of wet paper and I had to dig it out of the 12 inches of backstop soil. The bullet expanded to .701 caliber and weighed 524.4 gr. Weight retention was 98.9%!!! The bullets were cast out of straight wheelweights from an RCBS 500-PPB mold, patched with 16# layout paper and loaded over 36 grains of 3031. The greatest thing was that the velocity was only 1260 fps at the muzzle, I didn't think that it would expand at such a low velocity but I'm glad that it did. I can still up the velocity and expect the bullets to expand at longer ranges.

JBMauser · « **Reply #1 on:** February 15, 2005, 11:59:20 AM »

That is a formadable projectile for sure. Did you cast it with WW because that is what you had or choice. I have considered going softer and patching. I just got a mess of pure lead to play with. I am curios about the ability to load heavy bullets of that size in a tube feed with a PP jacket. I know it is preferable not to have too much crimp if any. with BP the bullet can't move as the case is full but with 36gr.?? lots of room to move but then they would move out not in!~ :? JB

jpuke · « **Reply #2 on:** February 16, 2005, 02:20:31 AM »

I use wheelweights because that's what I can afford. With 36 gr of 3031 and loaded to an OAL of 2.55" there is no empty space. I use a LEE factory crimp die on them because the patch does not extend past the top of the case - from what I read crimps are okay as long as they don't cut into the patch, but I don't have to worry about that with no exposed paper.

JBMauser · « **Reply #3 on:** February 16, 2005, 05:11:11 AM »

So you are saying all of the paper jacket is contained in the case and the factory crimp is brought down on paper and bullet or just bullet. I ask because I was under the impression that you needed to have the paper out of the neck so that it could not be contained and stripped from the bullet on release. a situation where you shoot the core out of the jacket. I realize this is not a roll crimp but just a tightening of the top 1/8 inch of neck. JB

jpuke · « **Reply #4 on:** February 16, 2005, 01:26:32 PM »

All the paper is contained inside the case and is actually 1/8" below the top of the case so I crimp on the bullet itself. I haven't had any trouble with leading so the patch must be surviving the trip out of the case into the rifling. My bullet also has a taper to it which must help. I like this also because there is no need to waterproof the patch for hunting loads when there's no exposed patch. I just went out today and shot some worked up loads and got an average of 1420 fps, I think I'll stop there.