bushmeister wrote:Thanks MB thats the one I followed. Well I just got back, and unfortunately got the same result
. so we know it's not lube or gas rings.
I ran the test, and it does not catch in the open position on the last round. It does, however if I manually pull it back.
That right there tells us that you are definitely not getting the gas pressure you need. So something in the gas system is out of wack.
What we know so far;
1.) It did work the first time you took it out. So something has changed.
2.) You checked the gas key and it's installed properly.
3.) You used the pipe cleaner on the gas tube (don't feel bad, they actually sell them for that purpose. I actually have some I bought years ago with my first AR, I just got lucky and was warned off before using them)
I'm gonna have to guess here that something got pushed in to block the gas some how (Though I'm kind of surprised that is has been forced out by now.
halfslow also has a good point, it could be that somehow you gas block has come loose or moved a bit.
If it was me this is what I would do.
1.) Remove the whole gas system. Gas Block, and Gas tube from the rifle.
This shouldn't be that difficult, it's just a matter of removing the screws in the bottom of the gas block (First put an alighnment mark on the block and barrel so you can put it back in the same place) then pull off the gas block, this will take the gas tube with it.
Then knock out the gas tube roll pin
Then pull out the gas tube.
Inspect and clean everything, make sure there is no blockage, then re-assemble. Use some red or green loktite on the screws to hold them in place (Red will hold better with all the heat, but will require a torch or heatgun to remove the screws later if you need to)
Go shoot it.