Originally Posted by Texas Star

Sort of. If there's a Model no. on the frame, they're okay for Plus P. But later ones prob. have improved steels and heat treatment. Some J-frames are marked as Rated for Plus P, but no K-frames, I think.

Keep in mind that heavy use of Plus P will increase wear, esp. cylinder endhake. Some deny this, but I've seen some loose guns, and the USAF cited this as a reason why they wanted 9mm autos, prior to adoption of the Beretta M-9.

T-Star