M66s are 7 shot now days. My two are the older 6 shooters and I've been CCing my 3" in a Hume JIT Slide lately. It IWBs well, too, I just find the OWB a lot more comfy and when I take the gun out of it at home, it's like it isn't there, yet ready to go out the door with the gun when I'm ready. I've done a full day with it and it's a lot more bearable than the IWB after a few hours. I'm thinkin' summer I'll be back to IWB if I wanna carry it, but I'm happy with it under a long vest in the OWB. I'm not sure I'd want an even FATTER cylinder in an IWB, but then, I'm a might tubby. LOL