I just noticed a slight gap that is slightly less than 2mm between my AK's rear sight block and front trunnion. I hadn't paid much attention to it before until I finally asked myself why my gas tube had always been a little offset relative to the lower handguard and I figured that gap is the reason.
Is this correctable or will the gun continue to function just fine? I haven't had any issues with it whatsoever after putting around 1,500 - 2,000 rounds through it. Bolt gets hung up a little when I rack it manually but I think that is caused by a really crappy tapco g2 hammer which isn't as rounded as other hammers I've seen (haven't done any sanding/filing work to it).

My ak is a lancaster arms rifle I bought back in 2011 (yeah, I hear their builds are shit). The serial numbers that match are dust cover, bolt carrier, bolt, and front trunnion. The gas tube does not have the same serial number as the other matching parts so maybe that can be an issue?

http://i8.photobucket.com/albums/a23/bearsredux/RearSightBlockGap_zpsb4059a20.jpg

http://i8.photobucket.com/albums/a23/bearsredux/Offset_GasTube_zps53e2d540.jpg

Yeeesh! Is the gas tube parallel to the barrel? Assuming it was always that way, it shouldn't be a problem mechanically. If it's a recent development, and the RSB is working its way forward, I'd be concerned about it manipulating the barrel somehow. As long as headspacing hasn't changed, you should be gtg, at least from a functionality standpoint.

Yeah, everything seems ok, it's just that gap that really worries me now. But like you said, if it is working its way forward then no doubt that'll cause some issues down the road. I guess the only way to find out is to keep shooting the damn thing.

It's a normal* product of how AKs are built.

On a AK the barrel assembly is built up and then pressed into the receiver. Each barrel/receiver varies a little. The gap is there to allow for the barrel to be pressed to the correct depth for that particular receiver.  The pin is then bored and pressed, which sets the headspace.

AJ

*As long as it isn't moving. If it moves stop shooting the rifle and get the headspace checked and the barrel repinned.

Hmm that makes sense. Thanks for the input. I'll be sure to track any movement and check the headspace from time to time.