I have a P99 .40. When I use Sellier & Bellot ammo, I get some that jam at an angle 1/2 way into battery, and sometimes it just does'nt go all the way into battery, and I have to give the slide a tap forward the rest of the way. Its doing it less the more I shoot. So, as a test I bought some Remington UMC, and it didn't jam once. When it first started this with the S&B, I polished the feed ramp. That seemed to make it a little better. Has anyone had a similar experience?