On the strength of the D frame Colt, here's an ad from the early 1950s in which Colt states the D frame can handle the 38/44 load. This is way, way more powerful than current "P+." I believe they were not lying, and the gun would not come apart shooting this ammo, but I probably wouldn't shoot thousands of 38/44s through a D frame as it would take a pounding after a while.