[556 CRS PRT with 660 rounds] All SBR, half FA. One thing the pictures don't do real justice on is the angle of the blast baffle. It is VERY steep, unlike anything I've seen. It can actually 'prick' your finger it comes to such a sharp point. I know that sounds wierd but it's true. Muzzle blast is being "forced" down one side of the blast baffle directly to a port. You can see the single "port" where gas is channeled through on the side of the blast baffle. The first two baffles are generously spaced apart followed by 5 very closely spaced baffles (all of which share an extreme angle). In total 7 baffles are present. The blast baffle is VERY thick and that trend continues throughout the can all the way to the last baffle before the end cap. This thing is a tank and it's easy to rationalize the 19oz weight.