Warning

 

Close

Confirm Action

Are you sure you wish to do this?

Confirm Cancel
BCM
User Panel

Page AR-15 » Troubleshooting
AR Sponsor: bravocompany
Posted: 11/17/2002 12:06:11 AM EDT
O.K. first off I don't consider my self an expert marksman but can usually hold my own when it comes open sights on my other rifles. I tried to set my battle zero today at the range and had some problems. I set up at 50yrds and cracked 3 off with the factory sight setting. I barely hit paper. Had to adjust windage ALLL the way left to get close to center. It still is a good 4" off center. Talked to Oly abd they said send it in and they'll take care of it. Still curious though how high above center should I be hitting. I'm not used to the peep sight but as far as I can tell i'm sighting properly but I'm atleast 3" above center. I doubt I should still be that high. My grouping pretty much sucked but thats probably partly my shooting and using PMP ammo which I know isn't exactly all that great. Another problem i had was trying to put a scope on. I have an inexpensive handle mount, maybe the problem? But neither scope I tried to mount had enough adjustment in any direction to come close to being sighted in. Would this be bad carry handle or mount or both? Or am I using the wrong type of mount? Would a scout mount be the one i need? I tried a bushnell holosight and an old simmons red dot. All in all I'm not very impressed in the performance of the rifle. Had a friend give it a try again with disappointing results. we were shooting on a bench without a real rest. Any advice?
Link Posted: 11/19/2002 5:17:40 AM EDT
[#1]
I am still a newbie myself and no expert on the AR-15 but did have a similar experience.

As far as having to move the rear sight all the way left, it is probably due to the front sight tower being mounted canted on the barrel.  Mine was, but has the 4 set-screw arrangement that allow you to set the rear sight to mechanical zero and then futz with the front tower to get the windage right.  From what I understand, if your front tower is the pinned-on type, you just have to be brave enough to plannish to fit (ie, hit it with a big hammer).

I also ran into trouble with the handle mount thing.  The first mount I got was a real cheap extruded type (<$20.00).  The trouble was, the mount has to seat all the way down in the handle channel and it is a pretty snug interference fit until the handle channel gets spread a little.  The cheap mount would screw on, look like it was OK but was not really seated. This made the scope point way above the bore line and could not be adjusted to hit where you wanted it.

I then ordered a more expensive ($50.00) machined mount that I had the same problem until I realized that I was not seating it all the way in like it is suppose to be.  Once I got it down flush, everything works fine. In fact, the cheap one probably would have worked OK if I had seated it flush.

Good luck and enjoy your AR-15,
Bill
Link Posted: 11/20/2002 5:29:04 AM EDT
[#2]
WAB,  Very sage advice,  But lose the advice about using a hammer to straighten out the canted sight.  The hammer will do more harm than good, and most of the time it just destroys the front sight tower.

The proper fix for a canted front sight tower is to re-install the barrel, if the barrel is using fixed taper pins.

Food for thought.
Link Posted: 11/20/2002 11:31:22 PM EDT
[#3]
Never whack anything with a hammer on an AR15!

If your sights are that far out then one of two things is wrong:

The front sight tower was indexed incorrectly and was drilled off center

The barrel is off center from the locating pin.

What Oly will probably do is to take your upper apart, check everthing for "true" and then reassemble it.
When it gets retorqued it usally comes into spec.

If that's not the problem then if the front sight tower will need to be replaced.
If it's not that then the barrel will have to be replaced.

Oly will make it right.

Link Posted: 11/22/2002 3:59:52 AM EDT
[#4]
Sorry about the controversy over the hammer.

My comment was not based on experience but on something that I remembered reading in the Derrick Martin (Accuracy Speaks) book "The Complete Guide to AR-15 Accuracy."

On page 239 in the section titled "Zeroing Problems" He says, "For minor corrections (10-15 clicks) a hard rubber mallet or dead blow hammer can be used to rotate the sight on the barrel. A considerable "whap" can force the sight against the pins in the direction desired. A relative large tool must be used, and it's not something you want to do in view of a paying customer. (If it's your own gun you may wish to close your eyes while doing the job.)"

He does go on to say that for larger corrections, the pins must be removed, the front sight base rotated to the correct position for the mechanical zero as determined at the range, the base loctited, the front sight pin holes re-reamed to the correct position and then the pins driven in the newly aligned holes.

Sorry about the confusion,
Bill
Link Posted: 11/22/2002 5:04:03 AM EDT
[#5]
WAB,
Don't believe everything you read, especially around here.  

Granted, that most of the AR-15 books written are not bad, it's just that most of the time, they only touch the surface of the subject, and never go into any depth.

P.S. If I ever caught a smith(loosely used) taking a hammer to my rifle, I would use the same hammer on him to straight his sights out.  Caveman clubing and gun smithing are not the same.
Link Posted: 11/22/2002 7:24:45 AM EDT
[#6]
hey can anyone benchrest/sandbag the FAR-15 and tell me what it groups. if its under 1.5 moa @100 yds ill likely get one.
Page AR-15 » Troubleshooting
AR Sponsor: bravocompany
Close Join Our Mail List to Stay Up To Date! Win a FREE Membership!

Sign up for the ARFCOM weekly newsletter and be entered to win a free ARFCOM membership. One new winner* is announced every week!

You will receive an email every Friday morning featuring the latest chatter from the hottest topics, breaking news surrounding legislation, as well as exclusive deals only available to ARFCOM email subscribers.


By signing up you agree to our User Agreement. *Must have a registered ARFCOM account to win.
Top Top