Need some advice

[meatsweats]

[Klem]

Yes, you can file the pin. It's only there to index the barrel.

Give it a tap with a hammer first. It may not have been tapped in far enough.

[FRB6.5]

Look on the bright side, you knew enough to stop and check that something wasn't right Vs gorilla it on and wreck the nut and the upper.

[meatsweats]

[meatsweats]

[brian y]

Sorry to read this, The only consolation I can offer is I have had good dealings with Right To Bear in the past and I hope they treat you right. As for the manufacturer I agree with you and would leave their barrels on the shelf and move on to a better barrel builder, Good luck

[grayfox]

Sorry to hear. Stuff can happen, this is the first one for BA I've heard about (there might be others - just not heard about them), and not trying to talk you out of your decisions. I have 4 of them and they all are fine.
Hope you find the barrel you're looking for.
Mark at PF has some uppers and stuff on sale right now, plus there's Brownell's with some Criterion barrels...
Or Lilja.
There are still several options for you.