Ejecting but won't lock back on last round

[pmc847]

Major oopsies on my part. Yesterday pulled the buffer and weighed it and found it is a carbine buffer at only 2.9  oz. Since that lower runs fine with my other upper I went down to the local Palmetto Armory an picked up a new lower and have a Odin Works adjustable buffer on the delivery truck. Just guessing here but I think my reasoning was 180 out and a heavier buffer might cause the BCG to travel farther backwards due to inertia. I should be able to test that theory Saturday or Sunday.

Not related to this thread but I am impressed by that low cost lower. It is every bit as tight on  the uppers as my Rock River match lower. The trigger is smooth with no take up and a nice crisp reset. A bit heavy but I won't decide on whether to replace it with a two stage unit until I test it in live fire.

I have a Geissely SSA trigger with 3 sets of springs to tune  to your preference.  High Speed Match, SSA E and Stock.  
Also Harris SBRM With S lock adapter and American QD piccatiny adapter.

Just in case you want to upgrade.  

Cheers
Philip