User Panel
User Panel
User Panel
|
Posted: 5/24/2006 5:33:13 PM EDT
[Last Edit: Dano523]
I'm not sure if this belongs here or in the Build it forum, but here goes.
I got a new RRA stripped lower and finished it yesterday. Upon attaching the upper, I discoverd a VERY tight fit around the rear takedown pin between the lug on the upper and the slot in the lower. In fact, it was so tight I had to use a rubber mallet to get the upper / lower to shotgun open and would never close 100%! Well, I studied it some today and decided to just machine it to fit. So out comes the Dremel tool and off comes the aluminum around the area where the lug on the upper goes down into the lower. (cutting out the lug relief area on the lower). BTW I had tried several uppers and all did the same thing. The upper would lack about 1/4 to 3/8 inch closing. Finally got it cut out so it will now allow any upper to close on that lower. My question - has anyone else seen this kind of problem? In all my builds, I never had. It looked like they just didn't get the lower machined out in the rear area. Unless I hear different, I think that will be my last Rock River stripped lower. |
|
|
|
|
Posted: 5/24/2006 5:42:42 PM EDT
[#1]
Rock Rivers are known for their tight lowers.
(hm . that sounds ghey  )Lets say tolerances  I have one that requires a good hand smack to close or open ; not a biggy. How much did you have to remove? Maybe you just got one on the high end of Tolerance? |
|
|
|
|
Posted: 5/24/2006 6:29:57 PM EDT
[Last Edit: j3_]
[#2]
Getting ready to change into someone more comfortable. Name changes coming.
|
|
|
|
|
Posted: 5/24/2006 10:42:35 PM EDT
[Last Edit: persimmonpete]
[#3]
I probably removed 1/32 inch or maybe a bit less. Before I started it did not have the channels at all.
Again, this one wasn't just hard to close. I had to use a punch to wedge the upper down and a pretty good smack with a rubber mallet to break it open. I did this maybe 10 times before I decided this wasn't going to just ease up with a few cycles. I checked a std RRA (got it as a complete assembled weapon) and it had some material removed prior to anodizing by the factory. Curious. EDIT - J3_ yeah that is a good idea about buying the ones I know are cut. Next time I'll do just that. |
|
|
|
|
Posted: 5/28/2006 5:19:02 PM EDT
[#4]
I just assembled my first RRA lower last night. After getting it all together I had the same problem. The upper I was planning on using would fit about half way into the lower, then get stuck. My bushmaster upper would not go on at all. I got out my files and went to work. They all fit now
 I won't use a lower without the relief cuts again. |
|
|
|
IA, USA
|
Posted: 6/3/2006 11:08:31 PM EDT
[#5]
RRA addresses this in their FAQ's and suggest a rubber mallet to help close the upper and lower a few times until it can be done without the mallet. I have a few that aster years of use are still nice and tight, I prefer it that way.
Jim |
|
|
OH, USA
|
Posted: 6/4/2006 2:21:32 AM EDT
[#6]
Got a link to there FAQ page?
|
|
|
IN, USA
|
Posted: 6/4/2006 3:04:17 AM EDT
[#7]
The following is from RB Precisions website. I use this method during assembly rather than removing metal from the lower receiver or the upper receiver lug. Works every time.
All of the Rock River Arms lowers are an extremely tight fit, they need to be worked in the following way : For the love of God make sure there is no rounds in rifle and it is on safe, the hammer will need to be back in the cocked position!!! Our lawyers make us tell you that death is possible if this is loaded when you perform this, we like our customers please do not shoot yourself! 1. Assemble the front pivot pin to the upper. 2. Lubricate the rear lug completely with a light grease (best) or oil, lube the inside of the receiver also. 3. Ensure the rear takedown pin is completely out in the open position (detent is holding) 4. Slowly push the 1/2's together, they will stick (THIS IS NORMAL) it will most likely not close completely at first this is normal. 5. Open and close, repeat being careful to keep the halves aligned, do not slam them together but continue to use increasing force to fit together, when almost completely together use a nylon or soft rubber mallet to tap upper receiver into final position. 6. When they are seated (little to no gap between upper and lower) lightly tap the rear takedown pin into place. This will seem scary to a beginner but it is natural for a tight fit. 7. You may see some of the anodized removed from the rear lug at the corners, AGAIN, this is normal. 8. You may have some difficulty separating the upper and lower, with barrel up and rifle unsupported (hanging in the air) grasp the rifle by handguard and give a "smack" to the top of the buttstock, you may need to do this repeatable, usually 5-10 times will do the trick. The guys at RB Precision are very helpful. THeir website has alot of good info too. Hope this helps!
|
|
|
|
Posted: 6/4/2006 3:10:21 AM EDT
[#8]
I had a stag lower that was like that at first, but after a trip to the range it was fine.
|
|
|
|
|
Posted: 7/3/2006 9:44:38 PM EDT
[Last Edit: sobrbiker883]
[#9]
Boy I wish I read this thread before I put together my pistol on a SunDevil lower.
Real tight. I got them together, and was damn near unable to get them apart. I decided to stone the rear tab on my flattop upper that came used with the pistol barrel as I always revert to my WECSOG mantra: "modify the cheapest part first!!"
-I will be replacing the upper receiver once I get all the bugs out of the lil bugger then I'll follow RB or RRA's advice......... |
||
|
|
WI, USA
|
Posted: 7/6/2006 7:52:07 AM EDT
[#10]
Did this twice now. The second was an extremely tight fit that didn't allow it to come anywhere close to fitting together for a while. With a little work doing the above and a little time, it fit. After shooting a few hundred rounds through it everything loosened up just slightly all is well. Both my builds fit like a glove with absolutely NO PLAY and do not require any extra force, hammers or any other bs to take down. Both are now perfect. 
|
|
|
|
|
Posted: 7/13/2006 3:09:38 PM EDT
[#11]
One other thing to note is that the recoil spring tube can project forward far enough to prevent the two halves from closing. I built a Stag lower with a 6 pos. CAR stock, and the buffer tube projected forward about 1/64th of an inch and prevented the upper from closing. Unscrewing the tube one complete turn was not really a good idea, as then the tube barely held in the buffer stop pin and spring. A better solution was to remove the tube and use a belt sander to shave off that little bit of extra material at the end of the buffer tube.
Now i'm just down to the tight fit problems everyone has probably experienced. No big deal - tap in the takedown pin with a rubber mallet, shoot it a few times, and it'll fit like a charm... |
|
|
|
FL, USA
|
Posted: 7/15/2006 12:43:20 PM EDT
[#12]
I wouldnt machine off any of the Uppers
they are Fine RRA Lower is the Problem! A EXTRA EXTRA Tight Fit doesnt Help Accuracy at all!! My bushmaster is petty tight and I have to use a PUNCH to DRIVE the pins out. Finally got a LMT Lower and it fits NICE I can push the pins out without a punch ! I think RRA should go MIL SPEC like Colt,LMT,Bushmaster except for my odd one |
|
|
PA, USA
|
Posted: 7/16/2006 6:52:09 PM EDT
[Last Edit: pantera1994]
[#13]
...
|
|
|
|
Posted: 7/16/2006 11:43:55 PM EDT
[#14]
There is nothing wrong with RRA lowers. The same thing happened with a Mega and a Stag lower with all RRA uppers, but you have to realize that there might be *slight* variations in manufacturers tolerances. Contrary to what FMJ said above, I did NOT advocate messing with the lower. In my case, the BUFFER TUBE from my collapsible stock projected forward too far when screwed in to align the stock correctly (and hold in the buffer retaining spring/pin). In that case, I ground off a little bit of the buffer tube to fit flush with the lower. |
||
|
|
MI, USA
|
Posted: 8/31/2006 5:10:01 PM EDT
[#15]
Man, it scares the hell out of me to force parts together and beat with a mallet. On the 6 RRA lowers I have used, the uppers were too tight, so I just took a file and removed just a tad from the rear and lower corners of the rear lug. It works well, and still leaves you with a tight gun.
|
|
|
|
Posted: 9/1/2006 7:51:42 PM EDT
[#16]
And I thought I was the only one.  My Del-Ton upper and Stag lower fit is so tight I can only move the rear takedown pin with use of a mallet and pins.
|
||
|
|
TX, USA
|
Posted: 9/22/2006 2:19:39 PM EDT
[#17]
My RRA upper ONLY fits in my CavArms MKII lower, and even there, it is TIGHT! It will only go halfway in my other lowers. I'll try the RBPrecision suggestion. I thought about replacing the RRA upper; it's nice to know that the fit is normal (for RRA's). I had a different upper that wiggled, which concerned me, though it was no less accurate than the others. Two extremes.
buckmeister |
|
|
|
Posted: 9/23/2006 7:09:04 PM EDT
[#18]
I would rather remove material from the lower so any upper would fit. As far using a puch to remove the rear take down pin, I have a couple of ARs like that. I found that if you remove some of the anodising from the inside of the rear lug hole, the upper and lower can be put together easily. I use a drill bit (by hand).
|
|
|
|
|
Posted: 9/24/2006 2:13:30 PM EDT
[#19]
Guys, the reason that I tacked this thread was to point out that the RRA lowers are tight as a norm, but will mate with upper through normal use/a couple of cleanings.
Now if you have an extensive problem of that of the bottom of the upper receiver lug being a tab bit too long and will not allow the two to mate, then you may need to mill the bottom of the upper receiver rear tab a bit. Now baring anything short of that last statement, don't file or grind anything down. Use lube and little force and allow the two to mate in with time. Failure to heed this advice will end up with a post in regards to "HOW DO I THIGHTEN UP MY LOWER TO UPPER FIT". |
|
|
|
|
Posted: 9/26/2006 11:36:52 PM EDT
[#20]
I have built at least 20 beautiful AR's using Rock River lowers, they are GREAT! My first time, like you, pissed me off, I thought, "what the hell", but after careful consideration, I decided to lightly dremel the upper corners of the rear lug on the upper. Why the upper and not the lower, well, the upper receiver cost less than the lower, and after dremeling just a little at a time and then applying "aluminum black", you couldn't even tell any work was done at all, I had a better fit than any complete factory gun I have ever purchased, and boy do I love a "PERFECT", tight fitting upper and lower. My builds are a better fit than any Colt, Bushy, or ANY factory rifle I have ever purchased complete. Keep on making them that way Rock River!!
|
|
|
|
Posted: 10/12/2006 5:41:09 PM EDT
[#21]
Just wanted to add my personal experience with a RRA lower -
I had no problems at all. Using a complete LMT upper, everything went together just fine, not loose, but definitely not over-tight. No need to use a hammer and punch to remove the takedown pin. So, not only do other lowers sometimes run tight, but not all RRA lowers are super-tight (though people do seem to have been complaining about tight RRA uppers lately). |
|
|
|
|
Posted: 11/14/2006 4:20:05 PM EDT
[#22]
I had to lightly relieve the rear lug on a Bushmaster A3 upper to get it to close on a RRA lower receiver. I took just enough off to allow a very tight fit on initial closing. Now after some use the parts seem to have worn together sufficiently to allow normal force to push out the takedown pin. As an old carpenter once told me "you can always take a little more off ... but you can't put a little more back on".
|
|
|
|
MD, USA
|
Posted: 12/6/2006 7:04:41 PM EDT
[#23]
Dang, I wish I would've read this post 2 nights ago. I just bought 2 RRA complete rifles. I assembled the first one with absolutely no problem. Everything mated up perfectly. I went to assemble the other and had the exact problem everyone here is discussing. It wouldn't even come close to mating up. With much apprehension, I got out the triangular file and hit each side of the upper just a couple of licks (just enuff to remove the powdercoat). Voila...fits like a glove now.
Fit and finish on the rest of the rifle is beautiful. |
|
|
|
Posted: 12/6/2006 7:22:45 PM EDT
[#24]
My STAG was the same way.
|
|
|
|
WA, USA
|
Posted: 12/22/2006 12:27:12 AM EDT
[#25]
I'm glad I found this, I thought I might have had a bad batch. I've got 5 new RRA lowers and 5 new factory RRA uppers and none of them fit together. One required the rear take down pin hole on the upper to be slightly widened. The other 4 are going to take a dremel. I started swapping things around and my Armalite, Colt, Superior Arms, and Mega uppers and lowers all fit each other and the RRA uppers with no problems. I'll skip the RRA lowers from now on, I don't care if this is "normal."
|
|
|
|
Posted: 12/24/2006 3:33:58 AM EDT
[#26]
My RRA lower also fits tight, but I have never had a problem getting it closed all the way.
|
|
|
|
|
Posted: 2/16/2007 3:12:55 PM EDT
[#27]
I've built up several stripped RRA lowers with no problems. Got two more a few months ago, different story. This ain't an issue of "tight fit", this is no fit no way. I tried a Colt, BM and RRA factory upper, no fit, period. I put together a Les Baer lower and had to drive the take-down pins using my brass hammer. But for these two RRA, I had to file the rear corners off the rear lug of the upper. Took off about 0.10" from each edge and only then got a tight fit. RRA didn't finish milling the inside of the lower. No other answer to the cause. Since I was able to fix it, no harm. But for a first time builder this would be unacceptable. C97 |
||
|
|
|
Posted: 2/27/2007 11:18:31 PM EDT
[#28]
+1 I am forever DONE with RRA lowers. |
||
|
|
TN, USA
|
Posted: 6/12/2007 8:16:32 PM EDT
[#29]
DaFuzz, thanks for the info from RBPrecision. You saved me alot of worry and headache. I just completed my first build a few hours ago. I used a RRA lower and RRA midlength A4 upper. At first, I could not get the upper and lower to go together completely. Following the instructions from RB, I was able to mate the two receivers. Just take your time, pay attention, don't use too much force, and I assure you, you will get your RRA lower to fit your upper.
|
|
|
TX, USA
|
Posted: 6/13/2007 9:26:22 AM EDT
[#30]
Since I started all this I have built two more RRA lowers. I have noticed a pattern here. I know that RRA does not build huge batches of guns like some others - at least I have heard from several sources that is true. They pretty much assemble as they go with orders.
Now maybe they have their lowers shipped to them without the final mil-spec milling because they want to do it in-house and make the fit between upper and lower nice and tight. Perhaps someone grabs a lower from the wrong tub for shipping - OR they ship it without the finish milling figuring we would rather have a nice tight fit by finish milling ourselves. Either way would be OK with me if they would just ask when you order which one you want. Or at least let you know they were shipping ones that wern't finished! But let me be clear as some others have. If you get one of these (2 of my 3 were like this) there is NO AMOUNT OF TAPPING THAT WILL MAKE THE UPPER FIT. You will shave metal on some - on others you are simply crushing metal. They MUST be milled out. Now that I know about this it is not really any problem and I end up with a custom fit upper/lower pair. Good luck - Pete |
|
|
KS, USA
|
Posted: 9/14/2007 9:42:01 PM EDT
[#31]
I just bought a new RRA upper to go on my old RRA lower and i am having the problem with the pin. The upper closes but I have to use a punch to get the back pin to go into the opposite side. Should I ream the block hole a little or just let time wear it in?
|
|
|
|
Posted: 9/15/2007 2:54:47 AM EDT
[#32]
Time wear it in through use, cleanings!!!!!
|
|
|
|
OH, USA
|
Posted: 9/15/2007 5:00:48 PM EDT
[#33]
The RRA that I built was so tight that I couldn't get the pin through unless you drove it in. I simply used 600 grit wet sand paper rolled up and removed a very small amount of material then finished it with 800 grit paper. The pin is still tight but it doesn't take a lot to drive it in. I like it nice and tight
|
|
|
KS, USA
|
Posted: 9/15/2007 6:58:34 PM EDT
[Last Edit: SASNAK]
[#34]
Well i really do not want to change the lower cause its fits perfectly with my other upper.
I do not want to make it loose for that one. So i will just leave it alone for now. Put 25 rounds her yesterday sighting in the scope and doing a shoot and clean every 5 rounds to break the new barrel in. Once i get a couple hundred though it I'll see if it loosens up some. I was seeing some pressure problems. It looked like the ejector was putting scrapes on the flat end of the cartridges around the primer. I was using loads i developed for my 24" heavy barrel for Pdog loads. 60G Vmax over 24g of benchmark. I guess the shorter 16" barrel maybe causes higher pressures. Both barrels are 1/8 twists. I read a great post in this forum on pressure problems and possible things to look for. This is a great place for AR information for us newbies to the black gun. I appreciate all your suggestions, recommendations, comments, rants and raves. Its all good. |
|
|
TX, USA
|
Posted: 11/22/2007 11:46:49 PM EDT
[#35]
|
|
|
|
CA, USA
|
Posted: 12/29/2007 10:40:02 AM EDT
[#36]
I just purchased a RRAs Coyote upper. Installing it on my Colt Sporter ( California Name Colt was forced to use) Plus mine required a Adapter Front take down screw.Any how it didn't fit.Starting to worry.Tried and tried. Then I took out the Bolt carrier and it closed with some effort.( Just to see if it would even fit) Some how that removed the bug,re-installed Bolt carrier group and was able with force to get it to close. I thought I was screwed but upon reading the problems others have had I guess I was lucky.
|
|
|
CA, USA
|
Posted: 1/21/2008 11:12:23 PM EDT
[#37]
I have 3 stag lowers and 2 yhm uppers and just one is put together with the same issues. I noticed that with the front takedown pin in place the rear is more than a blonde pushy hair out, I don't have a gage to measure. After reading this post I will file the lower than the upper only after trying the r&b instructions. I did shoot the rifle and she's g2g. Very disturbing on my first build to use a file to make it fit. I have had the misfortune of cleaning my fair share of m4's, abused and new, and I have yet to use a mallet to remove the rear takedown pin.
|
|
|
|
Posted: 1/21/2008 11:54:30 PM EDT
[#38]
They make them that way.
|
|
|
|
PA, USA
|
Posted: 2/12/2008 9:33:04 PM EDT
[#39]
|
|
|
IN, USA
|
Posted: 3/6/2008 12:23:34 PM EDT
[#40]
I bought some RRA lowers built 1 of them put a RRA upper on it and clips wouldn't fit after a lot of measuring i found the mag well was not cut in the right location it was shifter .040 forward causing interference with the upper so i check my other lowers and found all 4 of them are out of spec !!!!! I bought them at 2 different dealers 1 dealer just swapped me out a couple he had in stock (talk about customer service !) the other dealer didn't want to believe their was a problem at first and then wanted to ship them back for warranty well i had already called RRA they said they knew of the problem and had some set back to take of the "bad" ones the got out now dealer #2 tells me oh it's going to be a while they wont have those for several weeks ! I'm about to sell all my RRA lowers and parts and buy for a company that has some quality control ! Just a heads up for all you out there with RRA lowers here is how i found my problem print for an AR show the front flat of the mag well .225 from the back of the front pin or .350 from the center line of the front pin depending on who's print you look at but 1/2 .250 pin puts them in the same place an easy way to check them is put a .250 dowel pin and Mic across the pin to the flat it should be .475 +- tolerance sure not .435 .040 shifted forward ! |
|
|
USA
|
Posted: 3/17/2008 9:52:43 AM EDT
[#41]
I just had the same problem in a RR lower I pruchased yesterday (mating it with a RR upper as well). I about had a heart attack when it wouldnt close. I had to use a mallet to get it closed the first time.
After opening and closing it about 100 times, it seems to work without any sanding or dremel use. Im glad I found this thread! |
|
|
PRI
|
Posted: 5/26/2008 6:35:35 PM EDT
[#43]
Try www.RBPrecisions.com
|
|
|
KS, USA
|
Posted: 5/28/2008 10:44:56 PM EDT
[Last Edit: SASNAK]
[#44]
i recently got a new RRA lower and had same tight issue. Finally got the rear pin in and now my clips will not lock in. Anyone have this issue. Have tried several clips - all the same. Will not lock in place.
|
|
|
|
Posted: 5/28/2008 10:47:06 PM EDT
[#45]
Use the palm of your hand (with a hard slap) to seat the loaded mag upwards in the well against the locked B/C. |
||
|
|
KS, USA
|
Posted: 5/31/2008 10:00:08 AM EDT
[#46]
I have slapped as hard as i can - with no change. Something not right. going to send it back to RRA .
|
|
|
|
Posted: 5/31/2008 7:46:22 PM EDT
[#47]
With the upper locked into the receiver, look up through the mag well and confirm that the upper front edge is not protruding over the mag well top/front section.
|
|
|
|
|
Posted: 5/31/2008 7:46:28 PM EDT
[Last Edit: Dano523]
[#48]
Double post.
|
|
|
|
KY, USA
|
Posted: 6/26/2008 7:43:29 PM EDT
[#49]
I had the same problem with a RRA lower and a Bushy upper.
|
|
|
FL, USA
|
Posted: 7/2/2008 3:27:12 PM EDT
[#50]
Well if the lower needs to be modified to fit the upper, makes you wonder if the rest of it is in spec??
|
|
|
Win a FREE Membership!
Sign up for the ARFCOM weekly newsletter and be entered to win a free ARFCOM membership. One new winner* is announced every week!
You will receive an email every Friday morning featuring the latest chatter from the hottest topics, breaking news surrounding legislation, as well as exclusive deals only available to ARFCOM email subscribers.
AR15.COM is the world's largest firearm community and is a gathering place for firearm enthusiasts of all types.
From hunters and military members, to competition shooters and general firearm enthusiasts, we welcome anyone who values and respects the way of the firearm.
Subscribe to our monthly Newsletter to receive firearm news, product discounts from your favorite Industry Partners, and more.
Copyright © 1996-2024 AR15.COM LLC. All Rights Reserved.
Any use of this content without express written consent is prohibited.
AR15.Com reserves the right to overwrite or replace any affiliate, commercial, or monetizable links, posted by users, with our own.
