.380 ACP-21,500 PSI .380 ACP+P-N/A 9X19MM-35,000 PSI 9X19MM+P-38,500 PSI .40 S&W-35,000 PSI .40 S&W +P-N/A .45 ACP-21,000 PSI .45 ACP+P-23,000 PSI From what I can see, the JCP 40 and JHP 45 are identical (except internal chamber and barrel dimensions). I will guess the +P rated .40 will handle around 38,500 PSI like the 9MM. So it seems to me the JHP 45 wouldn't mind the 28,000 PSI .45 Super/.450 SMC. Double tap seems to think its .450 SMC is safe in full size +P rated guns. So if slide velocity can be controlled via spring, added weight, or both, I theoretically should be able to safely fire these cartridges?????????? Really guys and girls, near 1350 FPS from a 185 gr 45 will make anyone feel warm and cozy. Not to mention my range buddies might lose the whole "Saturday night special" attitude towards any firearm that cost under $500. It would be nice if the 4595TS could handle this as well.