Cee Zee said:
Can you explain why this would be true? I realize that the force of the slide is going to be stopped somewhere whether it's by the spring or a slide stop. The old "equal and opposite reaction" law comes into play. It seems to me that whatever method is used to slow the slide down to a stop is going to take the same energy either way.
When the round is fired, and the slide moves back, PART of the force of the explosion is passed to the hammer spring as the slide cocks the hammer for the next shot. THAT energy does NOT return to the slide as the slide returns to battery. (It comes back later, when the hammer is dropped, and basically has minimal effect on the slide stop.) -- the force stored in the hammer spring doesn't get applied until later.
Equal and opposite is a valid point, but the forces are managed differently when the slide goes back and when it goes forward. They aren't equally applied.
On the first part of the firing cycle much of the force is transferred from the slide and barrel (which are still connected) to the recoil spring and to the frame, through the base of the recoil spring guide rod (which rests against the receiver stop on the CZ frame as the barrel starts to move to the rear. Not all of the force is stored in the recoil spring, of course. Part of it goes to the hammer spring, part to the recoil spring, and part to the frame -- and then to your hand and arm. The slide stop doesn't really come into play during that part of the firing cycle until the barrel is all the way to the rear, and a lot of the force has already been stored, and then only as the barrel is guided down (on the CZ) and stops. Only a smaller part of the recoil force is hitting the slide stop
as the slide goes back. Much of the force has been transferred to the recoil spring and the hammer spring, and passed through the frame to the shooter's hand and arm. The force stored in the hammer spring is re-applied later, with the next shot.
An extra strength recoil spring retains MORE stored energy than a lower-powered spring, and if the gun continues to function (i.e., cycle, if the spring isn't too strong to prevent it) that extra force stored in the spring causes the slide to slam forward with extra force and it returns; the only thing stopping it then is the slide stop!
Cee Zee said:
BTW we might want to remember that the P210 was made in many calibers before the P220 came along.
You may be correct, but I've never seen
P-210s in any caibers but 9mm. .30 caliber and .22 versions -- and in my readings on the topic have never heard about other calibers and certainly not about a .45 version. I'm not sure that the P-210 grip frame could be made to accommodate the longer .45 (1.275") round than the (1.169") 9mm round! (That difference led to Glock create he .45 GAP, a shorter round needed fit a .45 bullet and case into a 9mm grip frame!! That's the reason other guns aren't easily converted to shoot .45 -- even if the rest of the design is (or can be made to be ) competent to do so.
Got as source for that claim about 210s in larger calibers??
Cee Zee said:
My understanding is that the .45 has greater felt recoil because the length of the recoil time is longer because it is slower.
I'm not ballistician enough to really address that point, but it seem to me that a larger caliber bullet that weighs a lot more, is moving more slowly, and is powered by more powder might have a bigger role in how recoil is experienced, and not just caliber alone...
Cee Zee said:
So I can't really see how a .45 would cause more damage to sliding parts or frames than a 9mm would as well as a .40S&W. The amount of pressure generated is what drives the parts and although the pressure isn't directly responsible for the damage it is indirectly responsible.
If you got that impression from anything I wrote, I certainly didn't intend to make THAT claim! Perhaps you're misireading earlier comments by others? The P220 was built originally in .45, but may have been first put into the field in 9mm.
Pressure is a player, but it's not pressure alone that causes problems. The bulk of the prior discussions was about guns designed to shoot 9mm (from scratch) then being adapted for (i.e., moving up to) a round that fired at the same (and, perhaps higher) pressure, but doing so while shooting a round that generated more force (larger bullet, heavier bullet, more powder, etc.)
.