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I am building my first AR. I am 18 and still learning about guns so no hating. Seriously. Anyways, can I afford to go on the cheaper side with the lower parts kit except the trigger? I was thinking of a geissele trigger.
No, go with a well respected manufacturer. DPMS does not fall under the designation. If there's one area I wouldn't skimp, this is it. There is a lot of stress on certain pieces of the lower parts kit.
Colt or Daniel Defense are the only ones I would use now that they are readily available in multiple online stores.
http://www.gandrtactical.com/cgi-bin/commerce.cgi?preadd=action&key=SPK99796
This is what I would do.
http://www.gandrtactical.com/cgi-bin/commerce.cgi?preadd=action&key=SPK99796
Most of the critical components would be in the Geissele trigger. You can skimp a little on the rest. Not sure what available kits are out there less the trigger group. G&R has the Colts, but that's over $60. I think Bravocompanyusa had complete DPMS in the $40s range. You probably don't want their barrels or Bolt groups, but for the small parts of an LPK, you're probably ok.
JP makes a LPK with no trigger, and goes for about $40.
These are some of the relevant threads you can read on the subject.
https://www.m4carbine.net/showthread.php?13773-Lower-Parts-Kits-brand-differences
https://www.m4carbine.net/showthread.php?37940-best-lower-parts-kit
https://www.m4carbine.net/showthread.php?91218-Highest-quality-standard-LPKs
SugarSkulls
11-15-14, 00:58
Rock River kit with a 2 stage trigger is nice and can be had for around $100 to 130 or so. There's a vendor on AR15.com that sells them for a good price. I would fit the trigger to the type of shooting you plan on doing.
I can't think of an reason to not get a psa or Anderson lpk on the cheap. I'd stay away from ptac lpks though.
SugarSkulls
11-15-14, 01:13
Joeboboutfitters kits have been good budget kits for some of my builds and if you are set on a nicer trigger, they have LPK minus triggers as an add on item if you buy the trigger from them. Giselles wife's company makes some nice milspec type and combat triggers.
RRA triggers are some of the crappiest and have some of the highest failure rates. I personally know 4 people in the last year who all replaced RRA triggers after very little use. Something like 1000 rounds give or take a couple of hundred.
Rock River kit with a 2 stage trigger is nice and can be had for around $100 to 130 or so. There's a vendor on AR15.com that sells them for a good price. I would fit the trigger to the type of shooting you plan on doing.
No, go with a well respected manufacturer. DPMS does not fall under the designation. If there's one area I wouldn't skimp, this is it. There is a lot of stress on certain pieces of the lower parts kit.
Colt or Daniel Defense are the only ones I would use now that they are readily available in multiple online stores.
http://www.gandrtactical.com/cgi-bin/commerce.cgi?preadd=action&key=SPK99796
Really, this is the one area? What parts have high stress in a LPK?
I'm with markm - barrels and bolts are the two biggest parts. If you use a quality after market trigger or get lucky with a good GI one, many LPKs will be fine, assuming they have all of the parts.
That being said, does anyone have any experience with the DSG kits?
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This is the best option I've seen recently: https://www.primaryarms.com/Spike_s_Tactical_Lower_Parts_Kit_Without_FC_p/slpk100.htm
RRA triggers are some of the crappiest and have some of the highest failure rates. I personally know 4 people in the last year who all replaced RRA triggers after very little use. Something like 1000 rounds give or take a couple of hundred.
I have 2 AR's with RRA triggers. One is a factory RRA, and the other I built. My RRA has just shy of 4k rounds through it and the trigger still functions properly. Supposedly RRA fits each trigger group to a particular lower during assembly
My build's RRA trigger "lost" the second stage after about 2k rounds. What I did was surface grind about .007" off the back of the disconnector that contacts the shelf that limits its forward rotation. That allowed the disco to make contact with the trigger's engagement area before the trigger broke, which gave me back the second stage.
What are the typical RRA trigger failures you're seeing? I'd like to know what to look out for.
...and sorry for the hijack
SugarSkulls
11-15-14, 08:40
This is the best option I've seen recently: https://www.primaryarms.com/Spike_s_Tactical_Lower_Parts_Kit_Without_FC_p/slpk100.htm
Primary has great customer service, don't hesitate to do business with them.
I have 2 AR's with RRA triggers. One is a factory RRA, and the other I built. My RRA has just shy of 4k rounds through it and the trigger still functions properly. Supposedly RRA fits each trigger group to a particular lower during assembly
My build's RRA trigger "lost" the second stage after about 2k rounds. What I did was surface grind about .007" off the back of the disconnector that contacts the shelf that limits its forward rotation. That allowed the disco to make contact with the trigger's engagement area before the trigger broke, which gave me back the second stage.
What are the typical RRA trigger failures you're seeing? I'd like to know what to look out for.
...and sorry for the hijack
The kind that force users to trash them or grind on them. Kindof like yours.
Really, this is the one area? What parts have high stress in a LPK?
The hammer for one. The pins holding the crap together is another example.
Also, you can go into tapacrap settings on your phone and disable the tapacrap advertising it slaps onto every post.
ETA: I now see the context of this was an LPK without the trigger group which has "most" of the components that would be stressed. Although I wouldn't want switches or levers breaking either.
The kind that force users to trash them or grind on them. Kindof like yours.
Have you had experience with the RRA triggers?
What I did was fit the trigger to a particular lower. If RRA had chosen to use a set screw for that adjustment, it would be a simple thing to do. Some other 2-stage triggers have user adjustable features
Toyoland66
11-15-14, 12:25
Really, this is the one area? What parts have high stress in a LPK?
Bolt catch for one, the safety selector is also a critical component that could render the weapon inoperable if it doesn't function.
A colt lpk from G&R with a QMS trigger will be about $100. It isn't worth screwing around with sub par components to build a rifle that your life could depend on, especially considering that every magazine you fire will cost about $10 in ammo.
Really, this is the one area? What parts have high stress in a LPK?
Uh yeah, the bolt catch for one. That thing needs to be pretty damn solid.
I don't skimp on any part of a rifle. But you can skimp on certain areas with little to no consequences. Flash hider (A2=$8), grips (A2=$3.50), stock (mil-spec-$24), etc.
Gotcha. I'm not saying it's not true, just that out of the whole rifle, the LPK isn't usually something people refer to as having high-stress.
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Have you had experience with the RRA triggers?
What I did was fit the trigger to a particular lower. If RRA had chosen to use a set screw for that adjustment, it would be a simple thing to do. Some other 2-stage triggers have user adjustable features
AR triggers shouldn't have to be fitted to a lower. The reason you had to grind on your disconnecter is because part of the FCG wore through the case hardening and to the softer material underneath and is now out of spec. Grinding on the disconnecter makes the situation worse because you now have another surface where the case hardening is gone. RRA 2 stage triggers have been known to wear to the point they double and triple. When they start that, they are just a few rounds from causing a run away
AR triggers shouldn't have to be fitted to a lower. The reason you had to grind on your disconnecter is because part of the FCG wore through the case hardening and to the softer material underneath and is now out of spec. Grinding on the disconnecter makes the situation worse because you now have another surface where the case hardening is gone. RRA 2 stage triggers have been known to wear to the point they double and triple. When they start that, they are just a few rounds from causing a run away
Thanks for the info...
Looks like a new FCG is in my near future. This may just be the excuse I need to get an SSA-E for that particular lower.
You're not serious are you?
Have you had experience with the RRA triggers?
What I did was fit the trigger to a particular lower. If RRA had chosen to use a set screw for that adjustment, it would be a simple thing to do. Some other 2-stage triggers have user adjustable features
Most of the critical components would be in the Geissele trigger. You can skimp a little on the rest. Not sure what available kits are out there less the trigger group. G&R has the Colts, but that's over $60. I think Bravocompanyusa had complete DPMS in the $40s range. You probably don't want their barrels or Bolt groups, but for the small parts of an LPK, you're probably ok.
I've had some DPMS sourced LPK's develop stupid tricks with the selectors and in-spec 2-stage triggers, it does work but it's not confidence inspiring to have ran across those problems. You can still do better for a touch more money and mostly patience.
The RRA NM (2-Stage) is bad. Seriously, for that money get anything else, there are threads here on why - I didn't think I'd have issues with the really low round count on mine, but it still is basically a garbage single stage already... TU in under 600rds had me wanting to break out the early 90's EDM in our shop and see how much better I could do with no prints or idea what I'm doing, they're that bad.
The DD LPK's are trickier to find, but those are a solid value; when Grant is able to source enough LMT and other parts to make the G&R LPK's happen those were absolutely unbeatable (especially with the G2S trigger option - I mean this was THE answer, I'm still grumpy I only have 4 G&R LPK's and as many SSAs in those lowers). Even though the Colt is pricy, it's excellent. I'd take the CMT (Stag) LPK over any of the other cheap answers (DPMS,CMMG,Spike's,PSA) because they're at least decent. I haven't ran enough rounds through my Armalite LPK Lower to have a really useful opinion, but I only have it because of the deal I got on the thing - where I can find them now it's still cheaper to go Colt/DD LPK and G2S so no reason not to do the latter.
LPK's aren't high stress items, but when they're out of spec it's a pain in the arse to sort out - especially for somebody new to the platform - so just spend an extra $10 on something that is a known quality setup and work from there, since it can cost that much in ammunition just to figure out why some small thing is going wrong. The trigger is the important part, but the G2S is every bit as good as the SSA in my sample size (one G2S, 5 SSA's) so that's an excellent candidate to keep the setup in budget.
You're not serious are you?
At the risk of looking foolish...Yes, I am serious. I'm trying to learn what I can
edit: just did a search and found a LOT of negatives regarding the RRA NM FCG. I'm taking that lower out of use until I replace the FCG
AR triggers shouldn't have to be fitted to a lower. The reason you had to grind on your disconnecter is because part of the FCG wore through the case hardening and to the softer material underneath and is now out of spec. Grinding on the disconnecter makes the situation worse because you now have another surface where the case hardening is gone. RRA 2 stage triggers have been known to wear to the point they double and triple. When they start that, they are just a few rounds from causing a run away
I didn't see evidence that the RRA trigger group parts were case hardened. They appeared to hard all the way through. The engagement surfaced were indeed still quite hard, still too hard to be cut with a file which should be 52 R/C+. When I replace the RRA FCG, I'll cut deep enough into the trigger casting and tack some rockwell measurements
I'm still serious
https://www.m4carbine.net/showthread.php?113430-First-precision-trigger-RRA-NM-Gieselle-SSA-LMT-2-Stage-or
https://www.m4carbine.net/showthread.php?60395-Your-thoughts-on-RRA-parts-kits-for-lowers
https://www.m4carbine.net/showthread.php?28640-rra-2-stage-trigger
https://www.m4carbine.net/showthread.php?75324-Triggers-single-stage-or-two-stage
https://www.m4carbine.net/showthread.php?99880-quot-Un-suckifying-my-RRA-quot-build
At the risk of looking foolish...Yes, I am serious. I'm trying to learn what I can
edit: I'm having a tough time searching and finding any info regarding the RRA NM trigger here?
Theblakester03
11-18-14, 02:14
Primary arms is legit. Very high quality for the price.
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outlawturtle
11-20-14, 16:38
Spikes makes some nice LPKs as well. I have both the enhanced and standards in a few of my ARs and have had no issues. I've also had no issues with my RRA 2 stage trigger and LPK with several thousand rounds through the AR, but apparently these are hit or miss.
-OT
I just bought Colt 3 lpks from G&R tactical. With the way things are going for Colt. Thought I'd stock up just in case.
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