Help! Bad mount?

[berettaprofessor]

Trying to mount a new 6-18 x 50 scope on a new 224 Valkyrie upper with new 2-piece Nikon P-series AR rings. Have used the P-series before on other ARs and like them. But today, needed substantial shimming of the caudal ring to zero scope with a laser bore sighter (indoors, 8 yds), and scope turret is at maximum elevation. Yes, I know the 8 yds isn’t ideal, but before when I’ve done that, at the range when I zero later, it is still sighted low, not high. Switched to another spare scope and same issue, so I’m suspecting the mounts? I switched them around with the same result. Should I be using a 20MOA anyway, given that it’s on a 224 Valk? Frustrating.

 

[troy fairweather]

did u fire the gun yet? those laser bore sighters are pos. even the old bushnell or tasco are much better. if u did fire the rifle the front of the upper may not be tru.

 

[illinoisburt]

Uh, dude! A 50mm objective on an AR with P series rings puts the centerline of the scope far above the barrel bore. Most flat tops are about 1-1/4 inches above centerlibe of the bore. Add in the distance of clearance of the bell (maybe 1/8 inch) plus 1/2 the objective (half of 50mm is about 1 inch). So your centerlines are going to be between 2 -1/4 to 2-1/2 inches apart. 8 yards is nowhere near far enough away for the angle of the barrel and scope to convene. If that's your starting point, adjust the scope to a point around 2-1/4" above the laser dot. That should have you close to paper at 100.

 

[z7]

Probably not a base/rings issue, probably the fact you are trying to bore sight an ar at 8yds with a scope that has limited elevation,

Is the mount on the correct way? 20moa in the wrong direction would make things real odd

How much elevation does the scope have (factory specs)

Try taking the upper off the rifle, taking the bolt out, and finding something 100-200yds away through the bore (like a light pole/fence post) then adjust the scope to show that at center,

Takes some trial and error, but should get you on paper at 50yds

 

[berettaprofessor]

The scope has 40 moa elevation. The current rings are flat moa, not 20, so reversing shouldn’t and didn’t make a difference.

Illinoisburt that makes perfect sense about the bore height. But the scope is below the laser dot and full adjustment and shimming just gets me to the dot. I’ll never get 2 inches about the dot without a 1/4” shim!

Going to fire the gun tomorrow.

 

[troy fairweather]

pull your upper of and your bcg and get the upper so it wont move, look out your window and find a target 50 to 100 yards away. look down the bore and line it u with your target outside the window, more your scope and u will be very close for your next range trip.

 

[243winxb]

scope turret is at maximum elevation. The scope is below the laser dot

If scope cross hairs are below the laser coming from the bore. Bullet impact will be high.

 

[jono]

And, I’m sure you checked this, make sure both rings are properly seated on the rail and that the cross bolt isn’t hanging up out of the selected cross slot. (Not that I’VE ever screwed and mounted one that way)

 

[243winxb]

turret is at maximum elevation.

Turn it the other way.

 

[berettaprofessor]

Probably not a base/rings issue, probably the fact you are trying to bore sight an ar at 8yds with a scope that has limited elevation,

Try taking the upper off the rifle, taking the bolt out, and finding something 100-200yds away through the bore (like a light pole/fence post) then adjust the scope to show that at center,

So, the winners seem to be Z7 with the advice copied above and Troy Fairweather in the later post! Yeah, the problem was me trying to get it sighted inside the basement on a cold night with an 8 yard zero and a stupid bore laser. I sighted it today directly looking through the bore out the window (which wasn't very easy given that small 0.224 bore and 24" length), but I was immediately cranking the turret back down. And when I went outside to shoot, it was zeroed at 25 yards in two shots and at 50 (my farthest safe range at home) in 2 more.

I left the shims in, which means the turret is actually near the bottom...so I have lots of room to eventually elevate for long-range adjustments....sort of my own 15MOA or so mount.

Thanks everyone, I appreciate all the good advice.

 

[cdb1]

those laser bore sighters are pos.

I have this laser boresiter and it’s definitely not a POS.
https://www.swfa.com/wheeler-professional-green-laser-bore-sighter.html

I also have two arbor boresiters. I use one of them to boresite levers and bolt guns. I then pop the laser on see if there is any difference. I use the laser boresiter by itself on AR’s. Have had the laser boresiter for four years and it’s had heavy use since I have a scope mounting business. It’s always been spot on.

 

[troy fairweather]

I have this laser boresiter and it’s definitely not a POS.
https://www.swfa.com/wheeler-professional-green-laser-bore-sighter.html

I also have two arbor boresiters. I use one of them to boresite levers and bolt guns. I then pop the laser on see if there is any difference. I use the laser boresiter by itself on AR’s. Have had the laser boresiter for four years and it’s had heavy use since I have a scope mounting business. It’s always been spot on.

u got one that is good. i have tried many at the gun shop i work at and most are not true with there center line.

 

[cdb1]

I actually believe almost all laser boresiters suck too. The Wheeler one doesn’t though. I didn’t luck out and get a good one, it is a good product.