Discussion in 'Rifle Country' started by Rittmeister, Mar 30, 2022.
My feelings about the trigger are purely subjective. I did not use a trigger pull gauge, just have time on both triggers. For reference, I was not trying to build target/hunting style AR's. I wanted to keep the standard mil-spec'ish trigger and build simple, durable, KISS AR's. I ended up with four rifles. Two have the ALG and two have the PNT triggers. After shooting them a lot, the PNT is smoother and has a better reset. All of them are much better than the factory Colt triggers they replaced. Those triggers were solid, but gritty. Those became back up parts for the rifles.
I am not a hard-core AR user or one who uses the rifle for work. I just wanted solid, simple setups with the least chance of parts breakage.
I don't think you can go wrong with either choice.
Here is a video from a respected person discussing AR triggers that you might find useful:
I'd stay away from anything with a adjustment screw. They come out of adjustment.
My experience with switching between two and one stage triggers has been less then charmed. Doing so under stress with a working rifle wouldn't be good.
Only if you let them.
I’m not aware of any specific posts or sites which detail the process I described, but I’m sure there are some out there. It’s not a complicated mechanism, so establishing stops for excessive travel and reducing resistance is pretty straight forward. I’ll offer some detail here.
In any trigger, we can evaluate pre-travel, creep, overtravel, and pull weight - and subjective FEEL as a measure of polish and spring/sear design. Mil-spec AR triggers don’t have pre-travel, often have excessive creep, often have excessive overtravel, and have excessive pull weight.
Creep: The plug screw in the grip reduces creep by limiting the downward travel of the tail of the trigger - reducing how far the front of the trigger moves UP into the sear cutout in the hammer. The same creep reduction can be accomplished by reprofiling the bottom radius of the hammer, reducing the height of the sear, but doing so without creating an uneven sear engagement is more difficult than simply lifting the tail of the trigger.
Overtravel: the AR FCG has a lot of room for excessive overtravel, so the shooter has a “mushy” back wall in the trigger follow through. Great triggers feel like “breaking glass,” but AR triggers will moreso feel like “falling through ice,” largely because of the long overtravel they allow. We really only need the sear to travel the 20-25thousandths of sear engagement, then sufficiently farther to not drag on the bottom of the hammer. Like the creep, we have two options of reducing over travel: we can stop the front of the trigger from falling too far, or stop the back of the trigger from raising too far. So a set screw or a glob of JB weld - or shimstock JB welded in place - either under the front of the trigger or on the flat of the selector barrel - OR in these respective parts of the trigger itself - can provide positive stop for the overtravel.
Pull weight: Pull weight is relatively easy, at least getting down to 3-4.5lbs, especially using commercial, non-mil-surp ammo. Swap the springs with a JP yellow reduced power spring kit, and you’re there. Going lower can be challenging, due to the positive inclination sear angle, as the hammer spring always influences the total pull weight - but most folks don’t want to invest in stoning jigs to properly recut square sear angles, and most folks are terrified about “cutting through the hardening” of sear faces, and nobody wants to reharden the triggers for such a cheap job. So we tolerate the acceptable 3-4.5lb ballpark we end up with.
Trigger feel: polishing the pivot pins, the internal bores, and the sear faces, combined with the weight reduction, creep, and over travel reductions will vastly improve the trigger feel. When we reduce pull weight substantially, we can often start feeling the grittiness present in the sear face when they’re not well polished. Smoothing this out can dramatically improve the stronger feel, and make the shooter relatively unaware of the amount of sear travel they’re still moving.
I really like the CMC triggers. I have several of the RRA two stage triggers you mentioned and really like them for my target ARs, but for a single stage drop in the CMCs are excellent in my experience.
Do you mean you would not have say 2 ARs with different kids of triggers? I have about 75 ARs I have built in a dozen different calibers with barrel lengths ranging from 7.5" to 24". I have 5-6 go to triggers I use on them and which trigger depends on barrel length and use of the rifle. Target rifles get 2 stage triggers. Match SPRs get a drop in single stage trigger. Plain jane models get standard Aero triggers while nicer models with enhanced furniture and parts may get an ALG trigger. I try to match my triggers to the level of the gun and the use.
I agree about triggers with adjustment screws. I stay away from them.
Thanks for all input, I appreciate having so much good advice.
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