I have a Liberty Leonidas 300bk upper. It's an 8 1/2" Lilja barrel with a large integral suppressor. 1/8 twist I am shooting Missouri bullet companies lead, polymer coated, 245gr bullets I have shot several hundred of these so far with no issues, but I noticed after doing a rapid fire on an already warm firearm, some of the bullet strikes were horizontal at 20yds. That wasn't happening during slow fire, and I have shot accurately with these loads at 100yds. The load is 12gr with accurate 1680. These are right at the 1000-1050fps range. Thoughts?