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Posted: 9/29/2005 8:11:07 PM EDT
I have a Car15 A1 Commando with a A1 Upper and to sight in in at 50yards the rear sight is all the way to the left of the upper. is the something wrong with the upper or is the barrel on too tight?
Link Posted: 9/29/2005 10:14:07 PM EDT
Link Posted: 10/1/2005 7:02:10 AM EDT

Originally Posted By Tweak:

.....or drift the barrel over by applying a no mar ( I prefer rawhide) mallet to the appropriate side of the FSB...........



Hey Tweak, along these same lines....

Since it is possible to "drift" a barrel into alignment with a mallet, how likely is it to knock a barrel out of alignment when using one of those front sling mounts (the kind that gives you a side mount up high in the FSB) with a good yank on the sling?  Is that something to be concerned about?
Link Posted: 10/1/2005 7:47:14 AM EDT
Link Posted: 10/1/2005 9:02:18 AM EDT

Originally Posted By Tweak:
....I've had my rifle drop 6 feet onto a concrete range floor and land squarely on the side of the FSB right after putting a 100 yd zero on it. Picked it up and the zero hadn't moved...... hr



Ouch!  A buddy of mine had his rifle fall off of the bench one day in a similar fashon.  It too, still had a perfect zero.  I was curious because of a barrel changing experience I once had.  When mounting a barrel, I noticed there was a very small amount of play where the alignment pin fits into the upper receiver.  I bore sighted on my neighbors house he
Thanks.
Link Posted: 10/1/2005 9:26:14 AM EDT
If it leaning way over, you may have to remove the barrel and adjust the alignment pin slot in the upper receiver. You need the tools to get the barrel off (upper receiver vice block, barrel wrench). Follow the sticky'd instructions in the "build your own" section here to remove the barrel, file out the receiver slot until you can get the FSB vertical, then peen the sides of the slot to tighten things up (otherwise, when you torque the barrel nut, the FSB will misalign again). Kind of a PITA, but the only way to get things properly aligned if the misalignment is drastic.
Link Posted: 10/1/2005 5:03:44 PM EDT
Link Posted: 10/1/2005 9:10:03 PM EDT
[Last Edit: 10/1/2005 9:12:34 PM EDT by rch]

Originally Posted By Triple_D:

Originally Posted By Tweak:
....I've had my rifle drop 6 feet onto a concrete range floor and land squarely on the side of the FSB right after putting a 100 yd zero on it. Picked it up and the zero hadn't moved......




Ouch!  A buddy of mine had his rifle fall off of the bench one day in a similar fashon.  It too, still had a perfect zero.  I was curious because of a barrel changing experience I once had.  When mounting a barrel, I noticed there was a very small amount of play where the alignment pin fits into the upper receiver.  I bore sighted on my neighbors house , and peened the excess play out of the upper, but alas, I still managed to miss a perfect zero.  It was 6 clicks or so off, and that was driving me crazy.  I took the barrel back off and remounted it again.  This time I got it perfect, but there was still a little play in the alignment notch in the upper.  It has been rock solid, but I always wondered if I could accidently knock it out.

Thanks.



Find the time to boresight your rifle at the range.  That's the proper way to do it.  Not pointing your rifle at a neighbor's house.  No matter how safe you are, things could still go wrong.  Stay away from liabilities/lawsuits.  Just plain common sense.
Link Posted: 10/1/2005 10:34:14 PM EDT
Link Posted: 10/8/2005 12:59:36 PM EDT
Built a Bushmaster M4gery that had rear sight all the way left when zeroed.  I noticed the front sight post looked canted to the left.  Read the "Build It Yourself" instructions for a barrel install.  Removed the barrel. peened the reciever slot, re-installed while bore sighting......and what do ya know.....It is now zeroed and rear sight is only 2 clicks left.

Should have done a little reading before the first install, would have saved time, frustration, and ammo.
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