So, the other day I fireformed 48 cases with 52.0 grs. IMR 4350 and 140 gr bullets. According to the Sierra manual, this was about 2 grs. under max for a 280. Today I took a new 280 case and filled it up to the top with 4831sc and did the same with a fireformed case. The fireformed case held almost 3 grs. more of the powder. Would you say this sounds about right? Been loading for many years but, this is my first Ackley.