Stock trigger won't kill ya. I went a different route, but that's because I love modding things and have a full understanding of the system and know what to mod without causing tolerance stacking issues. In the end, I use a Geissele SSA-E trigger and no firing pin safety as i've nerfed the gas system and recoil system just enough so that light primer strikes on chambering are not an issue.
Suppressors... well now that's a whole big assed can of worms. I've experienced severe suppressor shift in POA/POI with all suppressors with the exception of an AAC 762-SDN-6.
Even the Surefire SOCOM series has caused a significant shift. With suppressor mounted and the rifle zero'd, once the can was removed the POI would shift up far enough to give me a 400yard zero. It starts lobbing rounds like artillery shells.
Point of note: When installing suppressor mounts, torque to between 20ft lbs and 30ft lbs, with preference being the closer to the 20ft lbs side the better. Sweet spot for me has been about 22 to 23ft lbs. Beyond this torque range, the zero shift will no longer be a simple vertical shift, it will also start stretching threads and deforming the bore so that zero shift will also manifest in the horizontal plane as well. Rocksett is a necessity with these low torque values.
Another issue is gas blowback through the chamber and into the action. Some of this usually ends up on your face, in your eyes, and eventually in your lungs. Surefire generally has far less gas blowback than the traditional legacy designs although there are newer designs out now with far less blowback so if this is a serious concern for you, look into some of the newer designs.
All of that being said, I fully recommend Surefire above all else for sheer durability and ease of use, although my HK gun is currently set up with the AAC for the reasons noted above as well as the fact that it's closer to an old school DevGru clone with an AAC on it. The newer Surefire RC2 is supposed to be much better regarding gas blowback and is still built like a tank
Last tip, use a closed tine, non-comp flash hider. Throughout the decades and within the most current history of US warfare around the globe, many lessons are learned, forgotten, relearned the hard way, and possibly lost again. One of these is the use of open tine flash hiders, which is the current issue surefire suppressor mount for SOCOM.
They work great in mountainous terrain (without suppressor attached), in the open desert, and at a square range. But the moment you get them into the jungle, forest brush, or anything like it, they are ****ing terrible. Snag hazards of the worst sort. There is a reason the three prong flash hider on the original M16 went away. There is a reason the open tine flash hiders of the early 90's that were so in vogue with civ shooters never were adopted by the .mil side in spite of their superior flash suppression capabilities. Because they absolutely suck for true worldwide operational use.
