The oversized pins that came with the RRA 2 stage didn’t fit the CMMG lower (pins are too big). I had to use the small pins from the regular LPK to assemble the trigger. The smaller pins fit the holes on the CMMG lower nice and tight. The instruction stated to use the “oversized pins” with the trigger, and I’m wondering if using the smaller pins would cause any future problems(eg. pins walking out). Thanks for any info.
DO NOT SHOOT THIS!. What it sounds like is you have the trigger for the oversized Colt pins return it and get the one for the standard dia .154 pins.
According to the instructions, I do have the right trigger pin size because it states that the system works with a .156 diameter pin size. The oversized pins are .002 larger. I also searched and learned that RRA don’t make a 2 stage for the Colt pins anymore. There is no way the .156 pins would fit the receiver because the .154 pins are tight as is. The only thing I could think of is that the CMMG lower pin holes are tighter than the rest. I did do the function tests (step7 -10), and it performed as it should. The problem that is common with the RRA 2 stage is that the trigger turns sloppy and/or to a single stage after a number of rounds… So am I the only one with this problem?
CMMG’s holes might be smaller, but NM2S pins are going to be “too tight” in every receiver you put them in. they’re designed to be literally hammered into the receiver for an ultra tight fit. you can use standard 154 pins, if you dont like that. just make sure it doesn’t double on you.
Interesting about the slightly oversized pins. I have sold a few of these but never used one because of the reports. I would be leary of opening up the holes on my lower with a product that has been known to fail.
+1
Unfortunately, I hammered these pins into a irreplaceable CA-registered lower a couple years ago when the RRA NM triggers were the cat’s meow.
When the RRA trigger shits the bed, I have to ream the holes on a standard trigger and hammer for or use another RRA NM trigger. I don’t use an AR professionally, so I’m willing to afford the risk at this point. But if I could do it again, I wouldn’t bother with trigger groups requiring oversized pins.
I’ve also come across a post of someone having issues with a RRA NM trigger w/ standard pins due to the extra play in the hammer and trigger pin holes.
i think its rare, but i’ve heard of it too. a lot of guys run the NMs with 154 pins… i do in my SDMR and have in other weapons… without issue. there’s always exceptions, though.
the RRA NM is a good trig. everything fails eventually, but i’ve yet to wear one out, and they’re cheap, user friendly, and squeeze great in the mean time.
The oversize pins would not fit my 1999 Bushmaster lower (and you can bet I didn’t try to force an aftermarket part to fit). However, they do fit my grandpa’s 2005 Bushmaster lower. I think some lowers are just drilled a little larger. If the oversize pins fit, then use them…if not, then don’t worry about it…use the stock ones.
…then your receiver is out of spec
I had a problem with this too. I haven’t had a chance to swap setups, test or anything so I haven’t updated my original post yet. When I do I’ll let you know what happens.
I’ve got 2 carbines with the RRA triggers. I didn’t use the included pins in either carbine. I hate to ream out something that doesn’t need it and is not able to be put back to original condition.
On another note I did have a new, reputable lower that I was building on and had to use .155 KNS pins to get proper fit. Tolerances are a bitch sometimes.
I recently removed my RRA NM2 trigger from my Bushy lower. I replaced the factory trigger and pins. Now the hammer pin is very loose. I can fairly easily push it out with my finger. Would KNS.155 pin sets be the best fix?
The .155 would work since they also are secured but since you already had the .156 pins in there they will go back just fine as long as they will go through the FCG, which they should. I would try the .156 pins with your trigger and hammer. If you can get them in, you are good to go. If not the .155 KNS will fix it.