I have two H&R Model 157s (full stock), one in 22 hornet and one in 30-30. The 30-30 was cut down and a new recoil pad added in hopes my youngest could take advantage of the new Remington managed recoil round. I have shot the gun for years without a problem, BUT despite trying two seperate boxes of the managed recoil rounds, not a single one has fired. The pin is striking the primer and leaving a good mark, but no ignition. If you pop it out and chamber a full strength round, BANG...no problem. So, is it a weak firing pin spring or a different primer in the managed recoil round? Any suggestions? Thanks for your time.