Making 300 AAC/Whisper cases from military 5.56X45 cases

[m1903rifle]

Can the typical reloading dies such as Hornady or RCBS be used to form the 300 AAC case from a LC 5.56X45 case?

[barkerwc4362]

Yes. I use my Hornady dies to make 7.62x40mm cases from LC 5.56 cases. 7.62x40mm is just a longer version of the 300 AAC. I would suggest you trim the cases to length before you resize them. I trim my cases slightly long, then resize, tumble clean, and then final trim before I prime the cases. I use a drill press to do the trimming. If you are going to do a large number of cases it speeds things up a lot.

Bill

[m1903rifle]

Thanks for the reply