Outer barrel installation

[STRIK3]

I have a Classic Army M15A4 and I purchased a Madbull Daniel Defense outer barrel for it. After swapping the barrel and all the other sundries, I went to reassemble everything and now the plastic handguards wont reinstall because the delta ring wont tighten enough. I've found that on my particular gun, the delta ring has to be tightened all the way down or else the handguard cant fit into it. Using my delta ring wrench, I've tightened it as far as it will go, but it still wont tighten enough, even when I grease the threading on the receiver. Anyone have any suggestions or run into this problem themselves?

I took a photo of it, although I don't know how helpful this will actually be.
When installed correctly, the delta ring should sit flush with the front of the receiver.

[Captain Fox]

Your problem is with the same gun as mine, but my problem is different. The idiot who sold it to me glued the outer barrel in because he couldnt tighten it, and now after hours of trying to remove it the right way, i have to cut it off and bore out the hole.

[STRIK3]

Aha! Didn't see the two teeny-tiny screws at the base of the barrel that let you adjust the length to fit your handguard. Problem solved, herp derp. I'll wear my glasses next time I do work on my gun.