AR 9mm pistol barrel

[R.G.Gray]

I'm building a AR9 pistol and the barrel I purchased from LJ's AR parts does not have a pin.
Will that be a problem?

 

[jason867]

I'm not an expert by any means, but since it is a straight blow-back action, there are no locking lugs and no gas system to worry about aligning...

I think you're fine to use it. I can't think of any reason it wouldn't work.

 

[jason867]

I assume you're talking about the pin that clocks the barrel in the barrel nut area...

 

[jd4320t]

It'll be fine. Mine is the same.