Friend has a Pre-Ban Bushy Shorty. Installed a new Flat Top Bushy M4 Complete Upper and the accuracy stinks.

Neither of us know how to work on them beyond field stripping for cleaning and adjusting the sights. We do not know if the upper was put together by the person he bought it from, or Bushmaster. We do know the new upper is all Bushy parts and he switched out with the older A1 Shorty Upper.

Any idea what the problem might be? He can't even adjust the sights to get it to hit a can at 20 feet!

Does Bushmaster offer Gunsmithing services on their own rifles if you buy their accessories? By the hour, by the job?

Edited and posted question. I guess my standard links procedure does not work here?

Thanks.

Have you shot at paper targets to see if the shots are going into any type of a group?  The Bushmasters have in the past mounted the front post assemblies off of center which caused the 'zeroes' to be off center.  But I can't see that being so far off you cannot hit a target at 20 feet.

Agreed.

The "accuracy" is not off, just the POA/POI.

You need to get it on paper at short range, and dtermin where the shot group is to know what to do next.

That's what I thought too. I don't know if he shot at paper, but if my memory serves he did and could not get it on paper.

A friend suggested the sights may not have been properly aligned when everything was put together.

It's really frustrating because this is his first AR and beyond standard sight adjustments I don't know how else to help him.

I know I asked him the same question about paper and he said he had tried. I figured if he adjusted the sights all around and still couldn't hit a can at 15', something was wrong.

I'll get an update and get back here as soon as I can get a hold of him.

Thanks for the prompt replies.

Thanks guys. I'll get more info and get back.

Get it on paper.  You can always get it on paper at 10 yds... you just might need a little bigger paper.

First, center the rear sight for windage.  If it is an A2 rear sight, make sure the rear is bottomed out all the way.

Set the front sight in the middle of its travel.

Then, print it on paper.

If it is high/low, adjust the FRONT sight.  If you cannot get it into adjustment, then you have a rear sight that has been damaged/miss-assembled, or a frint sight post that has been modified.  I have one rifle that really had to raise the front sight post to the point it was loose.

If it is off left/right, then adjust the windage adjustment on the rear sight.  If you have to go all the way to the max setting, and it still isnt enough, then then barrel/front sight base has been installed incorrectly.  Take to a qualified gunsmith.

I have never seen one that would not get on a NRA sight in target (fairly big paper) at 10 yds.

Thank you very much sir. My friend advised that he tried repeatedly to hit a paper plate at about 20 paces and it kept hitting several inches to the right of the right edge of the paper plate. He made windage adjustments to all extremes which did change the POI, but the extreme windage setting never brought it back any better than several inches to the right of the right edge of the paper plate.

He is going to start over exactly how you describe the settings and at 10 yards and go from there. I do not know any qualified gunsmiths in his area, but we'll get the job done.

Thanks again and I'll report back.

Lets assume that your barrel is in line with your front site! probable not! some body assembled your barrel into the reciever and did not alline it so your barrel is in a straight line with your front site  , all else is impossible to do till somebody outs your barrel staight!  just a thought  .. bob cole

By that i mean if the barrel is not put in and tightned straight then it is off centered  and your upper sight is in also out off whack as both are not in staight allinment there for you wouldn't be able to hit the broadside of a barn at damn near any range!  check it out..  bob cole

Right. That is why he is going to the range again and starting over at the settings described above. If it is still that far off with adjustments, then we know there is an alignment problem that needs to be fixed.