Re: Remington 597 .17HMR Recall
If you make anyone of those components heavy enough then the bolt will not open at all. The area between wildly opening the bolt and not opening it at all is the timing and is controlled even in blowback operated guns. It can take time for the pressure to build to a point that it overcomes the inertia and the spring forces from the recoil spring and the hammer. I have never heard that the bolt starts moving immediately and that doesn't match the mechanics of the situation.
Having said that, it may be that the delay in starting opening can only be so great that the bolt will never fully open or so little of a delay that the pressures are too high and the case bulges as it moves to the rear out of the chamber. That is, the "good" zone is miniscule. Analysis like this needs to be done by engineers who design guns. Obviously Remington didn't do this analysis adequately and it was never done by the guys modifying 10/22's. The fact that so few manufacturers (was it only Remington???) brought out a 17 cal rimfire blow back operated semi-auto may be revealing as to the toughness of the task and that the 10/22 modifiers were just blowing in the wind with their conversion. I don't know for sure but always suspected the 10/22 modifiers were not doing it right (no engineering, just trial and error with lots of error).
But I have a hard time accepting your premiss that:
"the cartridge begins moving backward immediately upon firing"
That does not match the physic of it all, to me. Perhaps you would like to expound on the science of your premiss so I can understand it???
Last edited by LDBennett; 01-15-2010 at 11:47 AM..