[Martens]

I was at the range today and had my first "problem" with the XCR. It would not lock back on an empty mag. I tried several mags and had my buddy try them in his XCR and they all worked in his but not mine. If I cycled the gun by hand it would lock back on an empty mag.

I had shot close to 2K rounds of wolf since its last cleaning and lubing. I ran through settings 2, 3, and 4 and still no lock back but it functioned just fine. I checked the gas adjustment and it was properly seated.

I figured I would try some lube and hit the bolt and fired and it locked back every time. I guess there may be a limit to how much neglect an XCR can take before things happen, although it still fired, fed, and ejected, just no lock back.

 

[ny32182]

Yeah, I believe Wolf is normally considered to be underpowered. That, coupled with 2k rounds with no cleaning, and my guess would be that it was just short stroking by a very little bit, especially considering that the lube fixed it.

Cleaning is theraputic. And it helps the gun work. I'd be surprised that turning the gas up didn't do it though.

 

[Martens]

I was suprised with that as well as the problems started when I went down to #2 for the fun of it. I figured turning it up would have taken care of it.

I am not really disappointed as the gun still worked other than the lock back. I gave her a good once over tonight and she is slick as can be again so I am sure that was it as it was REAL dry.

 

[ny32182]

What is the total round count through it?

 

[Mick Nartin]

Martens,

One thing that came to mind when I read your post was how the bolt release on the XCR has a little wiggle to it. It's supposed to move really freely.

When I first got my XCR, the safety would stick so much that I had to use both hands to move it. I hit it with some Break Free and now it works fine.

Is it possible that your bolt catch and/or bolt release not sliding as easily as they should? The problem may be in that part of the receiver, instead of the actual bolt. Maybe some Break Free into the bolt catch and bolt release will loosen it up and allow it to move more freely with the mag follower. The bolt might lock back when you manually cycle it because it's not moving with the same force and speed as cycling under recoil.

Just a possibility.

 

[Martens]

I've lost track of round count but it is north of 5K.

I checked the bolt catch at the range and it was fine.

 

[Martens]

I would say I had negelcted my chamber for far too long. I gave it a very good once over today and the chamber looked pretty rough, okay real rough, especially compared to the finished product.

If I can shoot some of the dirtiest ammo for over a year and give it so so cleanings and the worst that happens is I don't get a lock back, I guess the rifle is pretty good to go. I have read several reports that wolf will dirty a chamber pretty bad as the steel case doesn't give as tight a seal as brass during firing. I would say I believe it now.

Oh well, once a year I guess I need to pay more attention to my chamber during cleaning.

 

[variablebinary]

Check the bold hold open.

It's two pieces. It's a pin that is cross stacked with another pin, but not threaded. So what can happen is the stacked pin gets pushed back for some reason and its set too far rearward to catch the back edge of the magazine follower. When the mag is empty the BHO stays down, and the bolt doesnt stay open

Tap the stacked pin forward again and be sure it comes into contact with the rear of the mag follower.

Robinson should make the BHO out of one piece, or use threading so it doesnt get pushed to the rear

 

[magikbullet]

good call vb3... has anyone mentioned that in the xcr improvements thread?