460 extraction issue
First there are going to be quite a few things to look at lets hit them one by one.
These are the things that I experienced before I HAD MY FRAME REPLACED.
I have 12" Performance center, and when shooting almost all my reloads and including the Hornady SST's I had very stiff extractions, even with mild loads I darn near had to beat the cases out. It happened more with the 200 grain loads than any other.
Almost all of my reloads and the Hornady's had flattened primers. Then something VERY odd happened, I took a close look at the primers and noticed what seemed to be primer cratering, where the primer flows back into and around the firing pin hold creating what looks like a raised crater around the firing pin dent on the primer (normally a VERY serious sign of overpressure).
I could not figure it out for the life of me as even the starter loads were doing this. Then, after a careful look, I noticed that where normally would be a bushing like on the 500 around the firing pin hole (in the 460's it is part of the frame) it had cratered into the stainless steel! Hence this marking was happening on each and every case. Check to make sure yours is perfectly flat!
In addition I was getting some decent flame cutting on the topstrap with those 200's from Hornady. I called S&W about it then send me a prepaid shipping label and then I got it back with a replaced frame! I still do not know why this happened but keep an eye on it!
Another thing to note is that be careful not to make the same mistake that I did with high power loads. Do NOT use WLP primers they are WAY to soft. Stick with Large Rifle Magnum in all your primers, the X frames have no trouble setting these off and they can withstand the higher loads. In addition the brass from starline and others is now with a seating depth to accept LRM primers and should be used (most of you already know this).
Another note of warning! DO NOT PUT ANYTHING NEAR THE CYLINDER GAP WHILE FIRING!
While on my last outing I had lost:
1. a cheeseburger that exploded and ended up all over my head.
2. 3 shell boxes that shattered from the pressure.
3. and a half full water bottle that I put just about 3 inches from the cylinder gap to check the pressures while firing to see just how dangerous it really was. It DECAPITATED the bottle and blew it up all over the shooting stall!
I had heard of a story that a guy blew a hole through his hand while holding the gun under the cylinder gap. I guess it might have been true