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jhend170
November 20, 2016, 21:15
Bought a brand new M1a Loaded with the ProMag precision stock. Sticking to the theme went ahead and got their low profile scope mount as well. I get everything together and finally off to the range yesterday. Go to the 100yd range, have NO idea where the rounds are going. Go over to the 50 and have the same problem. So, pull the scope and give the irons a go. After about 4 rounds I'm popping near hole-in-hole bullseyes. So I set the rifle up on sandbags with the sights centered on the target. Set the scope back on the mount and it's aimed a good 2ft right of the target, elevation seemed pretty good.

SO my question is how would you go about shimming the mount to correct the windage? I was thinking cutting some strips of aluminum from a can and placing them under the front end of the mount to bring it back to the left. However, if there are better ideas out there I'm certainly willing to listen.

So what say you?

jhend170
December 01, 2016, 18:59
Bumpity... anyone? Buhler?

TenTea
December 01, 2016, 19:21
2 feet off at 50 or 100 yards?

Does your scope not have enough windage adjustment to zero the rifle?

easttex
December 01, 2016, 19:43
I say there's absolutely no excuse for a brand new $2,000+ rifle not to be a tack driver. It sounds like either your scope, it's mounts, or the manner in which it is mounted on the rifle is defective. Put a different scope on it that you know to be good and try it again. If it works, then you'll know you have a defective scope. If not, and that scope runs out of windage, put your original scope back on it and take the whole lot back to where ever you bought it for warranty work. Something is mechanically out of alignment with the bore of the rifle and needs to be addressed.

ArtBanks
December 01, 2016, 19:54
Whatever scope mount you are using is off. I would suggest a Sadlak mount and take the time to install in correctly.

2barearms
December 01, 2016, 20:00
Springfields mounting points and or the mount are probably the problem.
It can be very difficult to see the issue without a second known good mount.

I have Arms 18 and a Fulton Mount that we could try and see if the problem is the mount or not. I'm in Houston if you want to give it go.

Jarhead504
December 01, 2016, 21:13
A SADLAK mount is what you need. I would 2nd a Brookfield Precision and then a Smith Enterprise or an A.R.M.S mount. Other mounts may work but not without a lot of work, The aforementioned mounts need LESS work to get them right. Scoping an M-14 clone is tricky business.

HTH,
Jarhead

jhend170
December 05, 2016, 23:14
Sorry all I hadn't realized I finally got some responses here...

jhend170
December 05, 2016, 23:15
2 feet off at 50 or 100 yards?

Does your scope not have enough windage adjustment to zero the rifle?

I'm seriously doubting that it would have that much. I think where I was hitting wasn't even in the field of view.

jhend170
December 05, 2016, 23:18
I say there's absolutely no excuse for a brand new $2,000+ rifle not to be a tack driver. It sounds like either your scope, it's mounts, or the manner in which it is mounted on the rifle is defective. Put a different scope on it that you know to be good and try it again. If it works, then you'll know you have a defective scope. If not, and that scope runs out of windage, put your original scope back on it and take the whole lot back to where ever you bought it for warranty work. Something is mechanically out of alignment with the bore of the rifle and needs to be addressed.

I'm quite certain it's the mount, but I haven't had a chance to pull and reinstall to make sure there's not something under it somewhere that is holding it out at the back. Guess I need to verify that first.

Once I went to irons though I was drilling it when I did my part. 3 adjustments and I was popping bulls. Quite certain the gun was doing its job.

jhend170
December 05, 2016, 23:22
Springfields mounting points and or the mount are probably the problem.
It can be very difficult to see the issue without a second known good mount.

I have Arms 18 and a Fulton Mount that we could try and see if the problem is the mount or not. I'm in Houston if you want to give it go.

That's an exceedingly generous offer. By some chance do you also have one of the in-chamber laser units? I think the combination would make it easy to see where the bore vs the scope are aligning. If not I'll pick one up and reinstall my mount first to make sure I didn't screw up.

jhend170
December 05, 2016, 23:23
A SADLAK mount is what you need. I would 2nd a Brookfield Precision and then a Smith Enterprise or an A.R.M.S mount. Other mounts may work but not without a lot of work, The aforementioned mounts need LESS work to get them right. Scoping an M-14 clone is tricky business.

HTH,
Jarhead

So I have quickly come to notice.

Jarhead504
December 05, 2016, 23:51
So I have quickly come to notice.

Also brother, like always when dealing with firearms, take your time, do not "force" anything, have patience, as plenty patience is required when dealing with M-14 clones. Don't work on them when you are tired or botherd by something else. Working on an M-14 type rifle is NOT something you do to relax or ease you mind, as in other "hobbies". It is more like trying to solve a rubic cube blindfolded while the colors are labeled in Braille.

Jarhead

ArtBanks
December 06, 2016, 07:00
If you want the best possible and most stable way to mount optics on an M-14 type rifle, you could always go to a Bula Defense Systems XM21. The rail is machined as part of the receiver during initial manufacturing.

http://i1180.photobucket.com/albums/x413/nf1e/IMG_0497_zps7m8qeyo4.jpg (http://s1180.photobucket.com/user/nf1e/media/IMG_0497_zps7m8qeyo4.jpg.html)

Semper Fi
Art

jhend170
December 06, 2016, 10:47
Also brother, like always when dealing with firearms, take your time, do not "force" anything, have patience, as plenty patience is required when dealing with M-14 clones. Don't work on them when you are tired or botherd by something else. Working on an M-14 type rifle is NOT something you do to relax or ease you mind, as in other "hobbies". It is more like trying to solve a rubic cube blindfolded while the colors are labeled in Braille.
Jarhead

So it's a woman... got it!

jhend170
December 06, 2016, 10:53
If you want the best possible and most stable way to mount optics on an M-14 type rifle, you could always go to a Bula Defense Systems XM21. The rail is machined as part of the receiver during initial manufacturing.


Semper Fi
Art

Definitely a fix SA should have looked into long ago, but I have faith that there are many thousands out there that have successfully scoped the standard receiver. Beyond that it's hard to justify tearing apart a new rifle, to build, a new rifle. Maybe one day I tackle a build, but it will likely be some years (and a few thousand rounds from this one) down the road.