Me, my wife and four AR15's.
#1 - my last AR15 build. Got the Ol' Blackface getting stepped on lower from PSA, a 16" chrome lined (sort of) medium weight parkerized barrel with a mid-length gas system (forget where I bought the barrel now but I looked awhile to find a chrome lined 16" ML gas barrel)remembered - DTI -Delton, Inc in NC. YHM gas block with the flip up front sight, A1 buttstock, a Matech BUIS, a magpul long carbine forend (to cover that YHM gas block/flip up front sight) and PA red dot with the promised 50,000 hr. battery life.
Sighted in the red dot. Close from first shot. Best groups (at 25 yds.) of all the rifles shot this morning. Some of the 3 round groups looked like a .30 caliber bullet hole. I like it. Could not sight in the BUIS. Nothing I tried would get the windage to adjust on the Matech. It was sighted in when there was a .300 BO barrel in that upper, but not with the .223 barrel in it. Gotta clean it, get that back sight moving left/right and take it back for another session. 100% function.
#2 - a previous "last AR15 build." It was short stroking the last time I had it to the range (which was also the first time I took it to the range.) Remembered I'd butted the gas block up against the step on the barrel rather than leaving that small gap (0.060"??) and adjusted for that between trips by loosening, moving it forward and tightening the set screws up again. It has one of those great feeling triangular like free float tubes from Luth-AR on it. Magpul BUS and a Cabela's 1X4 scope on it. Not happy with the scope set up. It needs to be further forward for me to get my nose on that charging hangle and I'm out of room to move it any more in that direction. Needs a differnt mount or different scope.
I shot it to confirm the scope was sighted in (from the last trip) and then removed the scope to sight in the Magpul back up sights. Pretty close from the get go, didn't take long/very many rounds. Put the scope back on it in the same spot on the rails and still good to go.
#3 - 10.5" AR15 pistol in .223. Took the Lucid red dot off it and installed a new PA (50,000 hr. battery life model). Got tired of the Lucid sight eating the battery with the red dot turned off and the gun sitting in the case.
Sighted in the new red dot pretty quick. Darn trigger is butt ugly. Till it goes BANG you keep thinking you forgot and left the safety in the SAFE position. After a few rounds the trigger finger actually starts to feel kind of tender/sore. Gotta replace that. Still, 25 yd. groups weren't bad. Let if pop me in the nose on the first shot, not bad, but enough to make me wonder what happened till it sunk in. i was shooting it from a bench, like I did the rifles/carbines and had my left hand trying to stabilize my right hand on the grip to keep the dot steady on the paper. Changed after that first shot to use my left hand to hold the magazine up against the back of the bench. No more nose kisses. Just that darn sorry trigger. I'm surprised the groups weren't more negativelly affected by that trigger pull.
#4 - the AR15 I built back in the spring with the 20" stainless barrel shortened/recrowned to 17" was last. It has another Luth-AR trianguler free float tube, Magpul back up sights, M16A1 stock (I like those things but they are getting harder to find in good condition), and a Vortex 1X4 illuminated scope. Previously sighted in, but short stroking. Same issue (on the surface as the other rifle. The gas block was not spaced out from the shoulder on the barrel. I "fixed" it, too.
This rifle impressed me on it's first range trip due to several .30 caliber sized 3 shot groups at 25 yds. It did better this time and only short stroked once. So, maybe not completely gas port vs. gas block alignment. I've had issues with two other rifles with shortened barrels. Both required a slight enlargement to the gas port (the closer to the muzzle the gas port is the quicker the gas pressure drops off after the bullet leaves the barrel - I know the bullet is moving fast but it can still be an issue if things are border line to start with.) I will remove the gas block and check the gas port as closely as I can with drill bits to see about where it's at for gas port diameter. And probably drill it out one step larger. That fixed the FAL (16" barrel counting the compensator welded to the barrel) and the 18" barreled upper with the rifle length gas system from PSA.
Not a bad visit. Maybe now I can get back to the pistols and see if I can get the M&P .40 FS working with that Storm Lake barrel, the FNS .40 shooting better with the 180 grain hollow points (still have some of the Blue Dot loads and Unique loads to shoot up), and get to work on some 124 grain hollow points for the M&P 5" FDE 9MM (that hopefully shoot well in the CZ's, too???).
Now, dogs to walk, pet, comb, treat and four AR15's to clean up/lube.
Edited to add DTI as the maker of the chrome lined barrel for rifle #1
and, all sighting in/test firing was at 25 yds. All ammo was Hornady 55 grain FMJ sitting on top of BLC2 powder with CCI small rifle primers.
