Just got back from the range for a function test and both rifles, the Plumb Crazy and my Armalite, are down in the gun room with barrels soaking in foaming bore cleaner...
I set up on the 25 yard range, since my primary purpose was to run a bunch of rounds through the Plumb Crazy and check for function and limited accuracy and didn't want to interfere with the shooters on the more serious longer ranges.
Comment 1: The trigger on my lower really sucks and has to be somewhere in the 10-12# range.. I didn't think it was ever going to fire for the first few rounds, but it did start to smooth out and the required pressure dropped down to approximately 6-9# after about the first 25-30 rounds...
Comment 2: I had taken the bolt carrier group out of the rifle and cleaned it from the excessive oil with which it was shipped and re-lubed it... I was a little concerned due to the stiffness it exhibited on the bench, but it functioned fine at the range....I swabbed out the barrel before leaving and only pulled minimal powder residue from the barrel and chamber..The seller advertised that the upper had been test fired and I expected to find the residue..
Due to the stiff trigger, I had no expectations of getting any kind of groups out of the rifle, but was pleasantly surprised as the morning went on...
The first target was a little ragged, mostly due to the trigger... I was shooting 5 rounds, cleaning lightly, then another 5 rounds, clean and let cool for 10-15 minutes and starting over again until I had the first 50 rounds through it....
You can see that my lack of group interest was showing in this one...
After the first 50 rounds and the trigger was getting somewhat better, I decided to see how consistent it could keep them together, and ripped off 20 rounds at a reasonably fast clip...That's the center group/hole...
One interesting side observation that I don't really have an explanation, I took the scope off of my Armalite (3-12x Sightron in a LaRue mount) and attached it to the Cheap Upper....The point of impact was basically centered from a windage standpoint, but the point of impact had raised approximately two inches at 25 yards....Both rifles are Flat Top receivers with about the same barrel configurations, but different quality barrels...
Ammunition used was Federal/Lake City FMJ in both weapons...
A better trigger is definitely in the future, but I'll keep the rifle....