Originally Posted by LONGSHOOTER
That velocity might be higher than it should be for a 21" barrel. Perhaps you're over max for that chamber.
You haven't solved your original problem from post #1. You were no doubt hot in post #1. Since then, you have enlarged your chamber by honing, changed powder and primer, and are using NICKEL ONLY cases. With a 21 inch barrel, you are probably still too hot. Sticking brass might be the indication.