I clearly remember an ad Lee ran in regards to an inflamatory response, (ad), by Blount, (RCBS), who stated at the time no factory ammunition was crimped on bullets that did not have a crimping groove. Lee retaliated with it's own ad, clearly showing .308 Federal Gold Medal Match Ammunition loaded with 168 Gr. Sierra Matchking Bullets, (which have no crimping groove), clearly crimped in place. The ad showed a pulled bullet with an indentation where the crimp was applied, putting a noticable ring on the bullet where it was crimped. Seeing as how case length can have adverse effects on the amount of crimp applied with a conventional roll crimp die, most all factory ammunition is crimped in a collet type of tool in a separate operation. Factory case length is not perfect. Or at least not as perfect as a careful handloader can achieve with a good trimming tool. What was intresting in this whole Lee, RCBS exchange, was the fact it was the first time a manufacturer spent more, ($150,000.00), knocking someone elses product, than they did in the same period advertising their own. Lee was quick to point that out as well. Bill T.