First AR build - range day

[Ridgerider]

What optic mount and scope are you using?

Did you use a square receiver face, and bed the barrel extension into the upper receiver? What about the gas block?

It's harder to shoot groups with a standard trigger, unless you polish the trigger nose and hammer notch engagement.

Heavy barrels need to be bedded in the AR15 receiver, unless you use a temp-fit.

No way should you polish the hammer notch and trigger nose (Sear) lap yes, polish no unless you want to ruin the trigger all together. Seen so many home wanabee gun smiths ruin a trigger because of what you describe. Thats why Midway and Brownells sell a jig to square and lap the trigger and hammer for correct angles and engagement.