MDI SLR receivers come loose.

It takes about 90 rounds before mine comes loose. Other then that works great. . . I bet it’s a common problem. I was thinking something like a spring plunger in the upper would be perfect. Then just insert a screw driver to push it in and slide the upper off the lower. If someone knows what nylock bolt to order please post.

http://www.swmanufacturing.com/parts-catalog/spring-loaded-devices/ball-spring-plungers/
 
It takes about 90 rounds before mine comes loose. Other then that works great. . . I bet it’s a common problem. I was thinking something like a spring plunger in the upper would be perfect. Then just insert a screw driver to push it in and slide the upper off the lower. If someone knows what nylock bolt to order please post.

http://www.swmanufacturing.com/parts-catalog/spring-loaded-devices/ball-spring-plungers/

That.....is actually an amazing idea. Wow. I mean there are ways of mating the upper to lower that dont require a bolt, but I think the reason it was designed that way was for a completely solid lockup. Likely to optimize accuracy.

However, if you're more worried about ease of disassembly then the spring and detent would be SICK.

The bolt itself is a 1/4-28 x 3/4" long. I'm working on finding a supplier currently. Apparently these aren't a regular stock item....Have a lead but wont know until Monday for sure.
 
Already on it. Actually also trying to track down a good source....will know more Monday.

Bahahaha, yeah you're right. This is CGN....no take-backsiesd:h:

Don't worry, if they switch to the fancy new bolt I'll still wait a year and buy the ATRS set instead, Lol

The barrel I bought finally showed.
IMG_20190102_130308.jpg

Don't hate me because I'm making it live in an NEA receiver till I get my ATRS MS set, :p
IMG_20190102_130557.jpg
 

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That.....is actually an amazing idea. Wow. I mean there are ways of mating the upper to lower that dont require a bolt, but I think the reason it was designed that way was for a completely solid lockup. Likely to optimize accuracy.

However, if you're more worried about ease of disassembly then the spring and detent would be SICK.

The bolt itself is a 1/4-28 x 3/4" long. I'm working on finding a supplier currently. Apparently these aren't a regular stock item....Have a lead but wont know until Monday for sure.

Upper and lower fit have nothing to do with accuracy. There were reasons for the bolt method vs others.
 
Don't worry, if they switch to the fancy new bolt I'll still wait a year and buy the ATRS set instead, Lol

The barrel I bought finally showed.
View attachment 238764

Don't hate me because I'm making it live in an NEA receiver till I get my ATRS MS set, :p
View attachment 238766

Oooooooo NO! Cr5! How could you?!?! Hahaha.

Hehe, jokes aside, that barrel is sweet though....Helical flutes are the cats meow. I need to get my hands on some cerakote.
Is that your complete MS build? I am loving it, thought I will admit I was never really on board with the CF handguards visually.

I've been hesitant to post my parts list for fear of being doxxed and murdered by DILIGAF and SSG69 lol
 
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Upper and lower fit have nothing to do with accuracy. There were reasons for the bolt method vs others.

Here you go again stating that "there were reasons" yet you once again fail to provide any reasons.

And don't give me any of that "but it was required to get NR status" nonsense.

If there were legitimate "reasons" I'd like to hear them :popCorn:
 
Here you go again stating that "there were reasons" yet you once again fail to provide any reasons.

And don't give me any of that "but it was required to get NR status" nonsense.

If there were legitimate "reasons" I'd like to hear them :popCorn:

Not my place to say anything. Sometimes you don't know what you don't know.
 
Have half a mind to try and convert my set to take an ar 15 pivot pin and mill that ugly lump off the front of the magwell. Have to do something to keep me busy till my MS upper gets here.
 
I know the receiver set has nothing really to do with accuracy. Someone mentioned how theirs was accurate and they were happy with it. I just said I was happy with mine as well, but was looking for a solution for the takedown screw.


How could anyone complain about that...

Accuracy and reliability of the AR platform is pretty much 0.5% dependent on the receivers. At the end of the day it's just an empty shell that houses the components that make the gun work.

Everything is in the barrel, cycling components and magazines.

The only time receivers can really play a part in the reliability of your AR is if you have an extremely worn out one (mainly trigger, hammer, and takedown pin holes) we're talking a gun that's been in service since the 60's and has no finish left anywhere... and even those still run.



So the argument that the SLR is good because 'it's accurate and reliable" is like saying the earth is round because the sky is blue.
 
I guess I missed this haha. Never mind! Following to see where I can order from.


That.....is actually an amazing idea. Wow. I mean there are ways of mating the upper to lower that dont require a bolt, but I think the reason it was designed that way was for a completely solid lockup. Likely to optimize accuracy.

However, if you're more worried about ease of disassembly then the spring and detent would be SICK.

The bolt itself is a 1/4-28 x 3/4" long. I'm working on finding a supplier currently. Apparently these aren't a regular stock item....Have a lead but wont know until Monday for sure.
 
Lots of MDI bolt derangement syndrome (MDIBDS) in here....

Between testing a .223 and 6.5 Grendel barrel with about 500 rounds downrange so far, my bolt has never been loose when I've gone to clean it. I've shot some ridiculously small groups so far and I have zero complaints about the hold down bolt, and actually prefer it to a pinned system. I had a large pin Colt HBAR before, and using the offset pin tightened like a cam and an accuwedge got it to shoot. If it was loose it wouldn't. Loosen the screws on your bolt gun and tell me that doesn't affect your groups.

I lube the bolt, and torque to 65 in.lbs. Your connecting rods aren't falling apart on your car are they?
 
I was fine with the bolt until my upper and lower came loose after a few rounds. I think the secondary bolt head should have overlapped the first bolt when tightened. If a nylock bolt fixes the problem sign me up.
 
Shhhhhhh please keep that to yourself or there will be a negative XCR thread started by people who have never owned one.

I don’t think it’s the fact that they use a bold system, that bothers the actual owners.
As they knew what they were buying.

I think it’s more to do with the bolts coming loose.
The company should just fix that issue.

I’ve owned two XCR-L key mod versions and the barrel bolt never came loose.
I think that wasn’t always the case though, but RA solved that issue
 
I know the receiver set has nothing really to do with accuracy. Someone mentioned how theirs was accurate and they were happy with it. I just said I was happy with mine as well, but was looking for a solution for the takedown screw.
My post wasn't all that much targeted towards yours honestly. Just the first line ;)

The rest is targeted towards everybody here who think something is good because of a reason that actually isn't one.
 
Shhhhhhh please keep that to yourself or there will be a negative XCR thread started by people who have never owned one.

Old news dude. And there were issues with the early xcr. I think robinson solved them with subsequent models? I don't know of the top of my head.
 
Old news dude. And there were issues with the early xcr. I think robinson solved them with subsequent models? I don't know of the top of my head.

They increased the torque spec is all they did as far as I know.
The negatives about the XCR barrel bolt were less about it staying tight and more to do with it just being a really poor way to mount a barrel where accuracy is concerned. The rest was just the lock-tite jokes about fasteners coming loose.
So there you have it, it's been known for years that bolts holding together black rifles is less than ideal, good thing these guys have been paying attention. :p
 
I was fine with the bolt until my upper and lower came loose after a few rounds. I think the secondary bolt head should have overlapped the first bolt when tightened. If a nylock bolt fixes the problem sign me up.

This^^^. I’ve been searching high and low for a nylock bolt but am having a hard time finding some.

I don’t think it’s the fact that they use a bold system, that bothers the actual owners.
As they knew what they were buying.

I think it’s more to do with the bolts coming loose.
The company should just fix that issue.

I’ve owned two XCR-L key mod versions and the barrel bolt never came loose.
I think that wasn’t always the case though, but RA solved that issue

Exactly.
 
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