Emf 92

[gasboffer]

I have a new EMF 92 in .357. I have been shooting plain base .357 dia. bullets, wheel weights, air cooled, at about 1100 fps. The fired cases have a slight bell and are marked like they have been hitting the end of the chamber. I tried some cases that were 1.280" length, same thing. There is a lead buildup at the beginning of the rifling, like a ring. Very hard to push a tight patch through. It's not like most leading, streaks lengthwise, i.e. Yesterday, I shot some 358156 gc, wheel weights, water quenched, about the same velocity, same results. Accuracy is very good before the lead buildup, but of course goes to hell pretty fast. Is there a chance the beginning of the rifling is square, causing the leading? I can't see the chamber well enough to tell what shape the leade? is in. This afternoon I'm going to seat a long bullet out in a fired case and chamber it to try to determine the length, it any, of the freebore. Any suggestions appreciated.
Clyde

[dragonrider]

"This afternoon I'm going to seat a long bullet out in a fired case and chamber it to try to determine the length, it any, of the freebore"

That's one thing you can do the other is to make a chamber cast of. Get some cerro-safe, it melts somewhere around 150 degrees. Get your bore and chamber very clean before casting. Use the search function for "cerrosafe" and you will find much info.