I have never used the bushing dies myself. When loading for the M1 Garand you do need to FULLY full length size your cases. The only primers that you should not use is Federal. I as well as others have had slam fire problems with Federal. The cup is to soft for the free floating firing pin. Do not use any bullet over 180 gr and no powder slower burning than IMR 4320 nor faster than IMR 3031. IMR 4895 was the military powder and is a good one. So is IMR 4064 and Varget. Don't use full house bolt action loads in the Garand. I would also suggest that you get a new operation spring right from the get go. I don't use a case past 3 reloads. 4 firings beats the crap out of the case in an Garand. I agree with Gen. Patton that it is the best battle weapon ever made. If you run out of ammo you can always club them to death and not worry about hurting it.