Originally Posted by TMD
only have 7 ar's and have been shooting and reloading for them for over 10 years now. Been though thousands of rounds so far.
Yes, that supports what I said: your personal experience just is not statistically sufficient to prove the value of the harder primers one way or the other. By comparison, a match at Viale range might have 300 rifles shooting 15,000-25,000 rounds over the course of the day (depending on the match), and there might be one slamfire all day long. You'd probably want to see at least fifteen or so slamfires to get a better statistical sense of how often they really happen, so we're looking at shooting maybe a quarter million rounds of standard primers against that same number of military hardness spec primers among a hundred rifles to get a realistic comparative sense of the level of immunity the military primers actually offer.
Fortunately for the statisticians, the military routinely fires millions of rounds retesting guns for barrel accuracy qualification, and they investigate every failure carefully to find the cause. That feedback helped develop their primer specs. Given their baseline data advantage, I see no reason to disbelieve their specs reflect the best design safety and reliability practices with their own weapons.
I suppose if it was just my own neck I was worried about, I might do the same as you do, based on my experiences with the Garand and M1A. The guy behind the gun is seldom fatally injured by a slamfire or an OOB fire's gun disassembly. Instead, it's the guy a wild round flying over the berm manages to find or the fellow on your right getting a piece of your boltface in his temple that you have to worry most about. That's the reason I switched to military spec primers. That's where the liability resides, as well.
I also think using these less sensitive primers is especially prudent for the novice reloader. He's more likely to have a high primer, which is generally agreed to be the most common cause of slamfires and OOB fires for handloaders. He's also likely to be a less experienced shooter, and so is more likely to suffer a lapse in attention in keeping the muzzle directed at the berm during loading. All in all, he's the one most likely to be the beneficiary of the added protection of the lower sensitivity.