I'm the guy who posted about the stove pipe jams in a new XCR a couple days ago. I was told that firing it another 220 rounds should cure the problem. I'm preparing to do that tomorrow and was giving it a very thorough cleaning tonight. All the parts slide very smothly, so I'm a little dubious that shooting it more will fix it, but I'll give it a try. Before I go out and shoot $100 worth of ammo hoping to fix the problem, I have a couple questions about the fit of a couple parts on my XCR. The owner's manual says the problem I'm having can be caused by the gas setting too low. I have mine on 4 and these things could cause low gas pressure. I can't find anything in the manual to answer these questions and don't have access to another XCR to look at, so I'm hoping someone here can answer these questions.
Is the gas valve supposed to be really loose in the gas block? Mine wiggles around easily (about 1/16") while held in place with the detent, and if it is moved to the position where it can be removed it will fall right out. It certainly is not making a tight seal in the opening. Is this normal? My only other experience with rifles that have a gas valve similar to this are an Aug and an MSAR STG-556. With either of those the valve fits rather tight even when clean and requires a pull to get it out after moving it to the removal position. My concern here is that gas is leaking out around the valve to the point that it is reducing the force on the piston. There is a groove around the gas valve about 1/8" in from the flange that holds it in place. Is there supposed to be a seal of some kind in that grove, or do the gas valves just fit really loose?
Is this normal for the gas tube to have a little bit of back and forth movement? I suspect it is, because the gas block is seated all the way against the shoulder on the barrel and is tight, but I've seen a new Springfield M1A that wouldn't cycle at all because the part similar to the gas block was not properly aligned with the hole in the barrel at the factory. That was easy to fix.
One other question that is just a curiosity. What is the "Barrel Extension?" There are references in the manual to cleaning it and inspecting it, but it is not shown in the disassembled view in the manual and I don't see anything I would call an extension on the barrel.
Thanks for any answers to these questions.
Is the gas valve supposed to be really loose in the gas block? Mine wiggles around easily (about 1/16") while held in place with the detent, and if it is moved to the position where it can be removed it will fall right out. It certainly is not making a tight seal in the opening. Is this normal? My only other experience with rifles that have a gas valve similar to this are an Aug and an MSAR STG-556. With either of those the valve fits rather tight even when clean and requires a pull to get it out after moving it to the removal position. My concern here is that gas is leaking out around the valve to the point that it is reducing the force on the piston. There is a groove around the gas valve about 1/8" in from the flange that holds it in place. Is there supposed to be a seal of some kind in that grove, or do the gas valves just fit really loose?
Is this normal for the gas tube to have a little bit of back and forth movement? I suspect it is, because the gas block is seated all the way against the shoulder on the barrel and is tight, but I've seen a new Springfield M1A that wouldn't cycle at all because the part similar to the gas block was not properly aligned with the hole in the barrel at the factory. That was easy to fix.
One other question that is just a curiosity. What is the "Barrel Extension?" There are references in the manual to cleaning it and inspecting it, but it is not shown in the disassembled view in the manual and I don't see anything I would call an extension on the barrel.
Thanks for any answers to these questions.