I was never worried about anything happening. Factory +P will not overly stress a S&W cylinder. I guess I should have said "to prove what would happen" (which was nothing) rather than "to see what would happen."

Yes, I shot all 1,100 rounds through the gun pictured. No increase in B/C gap or detectable end shake.

It sounds like that ammo you have is a 38/44 loading which is substantially more powerful than +P. A forum member once posted that he fired a bunch of 38/44 ammo (again, MUCH more powerful than +P) through his duty M&P in the late 1950s without effect. Elmer Keith wrote of shooting 38/44 ammo in an alloy Chiefs Special (J frame, pre-M37) in 1955 without effect to the gun.

Max for 38 Special is 21,500 PSI. The +P is loaded to 18,000. Standard 38 is now 16,000 (truly wimpy). The 357 Magnum is 35,000.

The K frame Magnum issue is another discussion. Just let me say that I have a Model 19 made in 1970. For 18 years it was federal agent's duty weapon. I have owned it for the past 22 years having bought it from the retired agent. He says the gun was never fired with anything other than full power 125 JHP Magnum loads. That's all I have fired in it. It's still like new. What do we do, now?

Member Stiab insists on doing what S&W says (actually, it's what their lawyers say). Can't go wrong that way. But they also advise against using any reloaded ammo. Is that also a good idea?

Like I said, everybody must follow his own instincts. If you worry about +P, believe it to be a powerful load, think it will harm a quality made gun, then don't use it. I have done a considerable amount of research on this matter and concluded that +P is exactly what it seems to be: a load that is 3,000 PSI below maximum. How can that be harmful?

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