first build - AR shots group out of sight adj range

[joedirt199]

i built this from parts since the mass shootings and now that it is all together the groups are 5" low and 3" to the right.  it shoots .5" groups at 25 yards with factory 55 gr ammo but when i start to adjust the sights to point of aim, i am running out of windage.  i have a fixed rear troy battle sight and a yhm flip front sight gas block.  i thought maybe the cheap dpms slick side upper was to blame so i bought the receiver truing tool from armalite and gave the front of the receiver a good polishing.  tighted up the groups and allowed the barrel nut to torque down to 80 ft/lbs right on a gas tube slot.  i have a 20" black hole armory ss barrel with 1-8" twist.  i was hoping to line up the sights without having to have much trouble but i don't want the rear maxed to one side to get it to work.  any ideas where else to look.  the upper and lower are mated rock solid. 

[SHOOTALL]

You might need to back off that 85 FT lb  to about 30-35 . Check out Mid Way USA on line they have a section on building AR's if I remember it says 30 . Seat it and loosen twice then torque in place use a good lube I used copper thread protector heat won't hurt it and it gives a nice smooth torque. . If your front sight is held on by screws instead of a pin thru. the sight mated to a grove in the barrel it could be rotated to give more adjustment in the direction needed.

[joedirt199]

the barrel torquing says to do the 30 lbs first then the next hole.  some say a max of 70-80 ft/lbs to make sure it is tight enough to not back out.  i did that a few times and set my torque wrench to 80.  before it would line up before reaching set pounds.  after truing the front of the receiver, it stopped right on 80 ft/lbs in the middle of a notch.  the gas block sight is a clamp on style so i am give it alittle cant to the right to see if it pushes the poi closer to center.  i also have a scope on the way and will try and sight it in that way to see if it is the sights that are throwing it off or something else. 

[SHOOTALL]

Well I have put them together , watched  a gunsmith build them and never seen one torqued that way or that high. Also never saw one loosen. 

[ironglowjr]

Hey joedirt i used to have this problem at the armory i worked at and it came to a few things .. 1st beeing barrel torque, second thing is the barrel alignment in the upper reciever notch. if this was the problem dremel a few thousandthson lft or right of notch so you can twist your front sight to correct impact point. sometimes the notches are incorrectly placed or the notches for sight are off. But before you go and get dremel crazy sight it in with a scope to make sure it shoots correctly to rule out other barrel flaws such as crown..etc..
Semper Fi

[SharonAnne]

any updates?

[Lloyd Smale]

theres the right answer. I had to open up the notch on two guns i built to get the front sight squared up.

Hey joedirt i used to have this problem at the armory i worked at and it came to a few things .. 1st beeing barrel torque, second thing is the barrel alignment in the upper reciever notch. if this was the problem dremel a few thousandthson lft or right of notch so you can twist your front sight to correct impact point. sometimes the notches are incorrectly placed or the notches for sight are off. But before you go and get dremel crazy sight it in with a scope to make sure it shoots correctly to rule out other barrel flaws such as crown..etc..
Semper Fi