

Not true at all. Many competitors use the M1-A (civilian version of M-14) and they handload their own ammunition. The only consideration in handloading is to ensure that the bullet is firmly crimped in the case mouth. The same is true for any autoloading rifle or handgun. Factory ammunition as loaded for the sporting market works fine in the M-14 or M1-A. Most factory rifle cartridges have a crimped case mouth, as the manufacturer has no way of knowing what type of action the user has. I hope this addresses your question.
Sincerely,
R. Mermelstein