So, I just finished installing and fitting a few parts to the Rock Island MS of mine. I refit the beavertail and trigger, installed a new disconnector, fit a new sear, used a "mainspring housing rebuild kit" and also changed out the recoil and firing pin spring, with a Wolf 23 LB recoil spring. I trimmed down the reverse spring plug to be flush with the slide, and swapped the full length guide rod for a gi guide rod. While there was not much of a change in balance, I prefer it with the gi rod instead, and disassembly is a breeze. I also changed out the firing pin although I've retained the spare parts "just in case." I plan to change the slide stop, and perhaps the barrel and ejector, in a few weeks. The barrel lugs are cut unevenly and when locked in battery you can press it down a couple hairs. It ran perfectly on the tulammo and PDX1s, obviously the pdx1s a little tougher recoiling, but with the new recoil spring, I experienced a lot less felt recoil, and I was very pleased with the performance of the work I had done on it. At about 75 yards, I was hitting point of aim give or take a few inches, with the irons, and at this point in time, it has no optics. It is extremely picky about ammo, and until I can get that sorted out, I don't want to waste the Black Hills stuff I have on it. It's a daniel defense chrome-lined 1 in 7 barrel, with a carbine gas port. I'm running it with a milspec reciever extension, and a heavy buffer, full auto bolt carrier, the works. On wolf and tulammo, it completely shortstrokes, without sticky extraction or anything, and ejects the spent round without going far enough back to chamber the next round, or lock the bolt back. Should i swap it to a regular buffer? It runs fine on 5.56(which it's chambered for), and i've read around that DD drills the gas port a little underspec on their carbine barrels to reduce recoil impulse.