Yep, conquer and divide. To find out whether it is an ammo or a gun issue, run Mini Mags. If the problem persists, look to the gun.
Make sure the chamber is absolutely clean. In the past I have lightly polished the chamber and radiused the mouth with
a tapered stone on a Dremel tool followed by water based valve lapping compound on cloth to polish. The radius should be very small, just enough to take away the edge.
This worked on an after market barrel with tight chamber. I just used Flitz on 0000 steel wool and that was enough.
