I'm trying to work up a load with RL-17 but keep getting flattened primers in my 30-06.

Max load is 54.5 with a 180gr bullet. Alliant says you can use 4350 loading data which I do and minimum load from Nosler's book shows 51gr of powder and max of 55. I had a .40 3-shot group @ 100 with 53gr of powder

Savage 111
Winchester Bras
CCI 200 Primer
180gr Accubond
.010 off the lands



I've loaded 50 and 50.5 and still get flat primers.

Any ideas? Do I really need to drop in the 40's?