i am reposting this from another site:
BG 380 + Polycase ARX Interceptor = split frame
Just a heads up, I was able to locate some of the new Polycase ARX/Interceptor ammo in .380, bought 4 boxes. I researched the round, seemed worth trying as a carry round. I fired 6 rounds of FMJ to warm up, then loaded 5 rounds of the Interceptor. Upon touching off the first round, the gun nearly exploded in my hand. Luckily, I was wearing gloves and wrap around eye protection. Debris showered my face, and the frame is split right down the entire grip. My hand was stinging pretty badly, I removed my gloves expecting to see blood but the gloves absorbed the impact/gases. Right thumb was pretty beat up. It appears that the round was way too hot for the gun, and shoved the slide back with such force that it split the frame. The laser is also now dead as well. I sent an email to S&W with a couple of pictures, waiting to hear back.
At this time, I would suggest extreme caution if using these rounds in ANY small .380. I can't imagine what a KelTec would do with this round; fortunately the S&W was able to hold the slide and not send it back into my face. This all from a tiny .380, with a 56 grain bullet.