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Posted: 4/13/2005 9:30:48 AM EDT
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I just completed my first build and have a couple questions/concerns. 1) I can't engage the safety with the pistol grip tightened. If I loosen the bolt just a touch it will move from safe to fire and back again but when tightened down I can't switch it at all. I'm using a Magpul MIAD grip, that appears to have a beveled edge that the detent spring sits on but there is a hole that extends deeper, should I be trying to shove the spring into the hole (past the beveled edge)? This seems like a situation where the spring has fully compressed too early. 2) The bolt catch doesn't catch. If I push against the spring side of the bolt catch while pulling back the charging handle it will catch but just the force of an empty mag doesn't force the bolt catch to the up position. I have LaBelle mags with MapPul enhanced followers and Ranger Plates if any of that matters. 3) My RRA two stage trigger feels like the stages are reversed, I have a really light pull to take up the slack and then a much firmer pull to release the hammer. I haven't taken a spring scale to it but it really seems backward. Is it possible to install incorrectly so that the light force would be in the first stage? Those are all of my problems for now (I think that's enough), thanks for any help you can provide! |
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I think your selector detent spring needs to go into the hole you mentioned. If for some reason it won't line up right, you can usually get away with a disconnector spring in there. I did that by accident on my first and it's still there and seems to work better than any of my others. Your bolt catch is probably just a little stiff. That always happens when I have a stubborn roll pin. You should be able to work it around a while and loosen it up. If you are impatient you can just drop the hammer on it a few times. |
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Yes the hole in the top of the grip is for the selector spring. I'm surprised you got the grip installed without having to put the spring into the hole in the grip, but I am only familiar with standard A2 grips, so I'm not sure what's going on. Try taking your pin punch and lightly rapping on the roll pin for your bolt catch. If something is binding it might shake it loose. The only other thing I would offer is to ask if you are sure you used the right springs and detents in the right places. The selector detent looks as though it will work as the bolt catch plunger. This may indeed explain both of your issues if you got them swapped around... In my DPMS LPK's the selector detent is golden colored with a conical nose and the bolt catch plunger is black with a cylindrical protrusion that rides inside the bolt catch spring. Likewise the bolt catch spring looks an AWFUL lot like the disconnector spring. The disconnector spring is tapered though. The wide end of the taper sits down inside the trigger body. The taper keeps it tight inside the trigger so it will not shift around or possibly pop out as far as I can tell... I hope you don't take this advice as condescending because I don't mean it to be. I made both of those mistakes myself on my first build! Sorry I can't help you on the trigger, but generally the first stage on most triggers is light and long and the second stage is short and crisp. Doesn't sound right for an RRA trigger though, but I've never had one personally. I hope someone else can help you there. Finally, there are some threads tacked to the top of the BIY forum that have excellent instructions with pics of all the springs beside each other so you can compare them. There are also assembly instructions under the "information" button at the top of the webpage... EDIT is done. Please reread if you thought I was completely retarded the first time you read this. Hopefully I only seem somewhat challenged now! :) |
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Oops, reading this (and taking a look at the parts ID in the guide section again) I think I used my bolt catch spring as my selector spring (which is why it doesn't fit down the hole in the grip) and used my disconnector spring as my bolt catch spring. It still seems to me that the first stage on my RRA NM trigger is WAAAaaay too light though. I was under the impression that once the first stage was pulled the second would take just the lightest touch. Mine takes very little to take up the slack and then a definite pull to release the hammer. Maybe this is correct and I was mistaken in my expectations though. Anyone care to clarify for me? Thanks again. |
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I will edit my last reply. I wrote it in a hurry and re-reading it I found it hard to understand. Please check it again in a couple minutes. Sorry if I gave anyone a migraine with my rambling rambles... Guess I should write once and read twice or something like that, huh? Ray |
While I don’t have a RRA 2-stage trigger, this basically sounds right to me. The first stage is long and light, the second stage is short and at least somewhat heavier. That extra weight is how you know when you’ve reached the second stage. After all, you couldn’t have the first stage with a stronger pull than the second stage since - once you got to the second stage - you’d fly right through it and release the hammer. If the RRA trigger is adjustable (my recollection is that it isn’t), you probably can lighten up the second stage a bit, but AFAIK the second stage will always be heavier than the first. |
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I didn't expect the first stage to be heavier than the second but I also didn't expect the differential of force from first to second to be so large. I thought that the first stage was generally around 3.5 lb and the second an additional 1 lb (totalling 4.5 lb on the second stage). It seems like I'm adding much more than one third of the original force to trip the second stage. Guess I'll just have to stop all my subjective thought and throw a fish scale on the thing to get some hard numbers to share. Thanks for the input! |
It sounds like you are confusing it with a set trigger. |
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FWIW – I just measured my Armalite 2 stage trigger (non-adjustable). Note that it’s well used, which may have lightened it a bit. The first stage is a long 44 ounces (2.75 lbs.); the second stage is a crisp 68 ounces (4.25 lbs.). This IMHO is just about perfect for normal usage. In theory at least, the second stage should feel lighter than it actually is since you’re already applying pressure to the trigger. For example (using the above trigger), you’re applying 44 ounces of pressure when you get to the second stage, which needs 69 ounces. Thus it should feel like you only need 25 ounces to trip the second stage (69 minus 44). Gotta admit your trigger doesn’t sound right. |
The spring should fit into a hole in the grip... period.... probably about 1/4" to 1/2" of spring in that hole.... if it isnt, thats WAY too much force ont he selector.
This is common. Three things to check.... (a)make sure the bolt catch hole for the roll pin is larger than the roll pin, it should be able to swivel freely. (b) Some catches are out of spec, so remove it and sand it with fine grit paper to remove any burrs, polish the surfaces, and even remove a little metal if needed. (c) Some lowers come with grit and burrs in the catch slot, so runb some fine sandpaper inside this hole to slicken it up and make sure it is clean. Then reassemble DRY, and work the catch back and forth manually pushing on the bottom about 100 times. Problem solved.
Totally normal. Should be very light takeup, with a heavier break. Some are lighter than others.... they can be tweaked easily if it bothers you. The 2nd stage will get a little lighter with some use, and you should lube this a bit with moly grease. Shoot it for several hundred rounds, then see what you think. |
This is common with new parts. It's caused by the extremely sharp point on the top of the selector detent. Take a file and blunt the point and your selector will work smooth and easy. |
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I got the springs in the correct spots now. The safety now moves just fine and the bolt catch catches in about 95% of attempts (I think with a little time that will become 100%). I think I just had the wrong expectations for the two stage trigger. I'm going to try a buddy's here in the area and see if they are roughly the same but based on all of your feedback I'm guessing they will be. Thanks for all the help, time to hit the range and site this thing in. |
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