Ran out of elevation

[Ruger007]

The gun is a Savage Axis in 308.
I have tried 2 different sets of rings. First set was Talley 2pc and second set is a Leupold dual dove tail both in mediums.
I have tried 2 scopes, Leupold vx1 3-9, and a Bushnell 6-18
With Talley both scopes ran out of elevation. So I tried a set of dual dove tail rings and bases. But this time I only used the bushnell scope. Still a constant 4" low at 25yds. Windage is perfect.
The rings have been lapped.
I have used the Talley mounts on a different axis in 223 with no problems.
Is it time for a shim and how much?
I have mounted lots of scopes before. But never ran into this much hassle to even hit paper! WTF.

 

[Peecos]

Sounds like you’re going to need shims under the rear base, aluminum can shims will work cut to the same dimensions as the base with screw holes or more simply a 20 moa one piece rail. Factory issue, it’s happened to me before.

 

[grauhanen]

You might consider Burris Signature Zee rings that can use the offset inserts, +/- 0.005, 0.010, and.020 MOA.

 

[Redblack]

+1 for signature Zee rings. Mix and match the inserts until your happy.

 

[nitro-express]

Hate when that happens. Usually means the barrel and receiver are not on the same axis, (no pun intended), or the barrel is crooked. Had a 25-06 that when you looked down the bore it looked like 0. Took a heck of a lot of shimming to get it sighted in, but it would string the shots unbelievably. What a waste of powder and bullets.

If you open the bolt and look down the muzzle, is the firing pin hole centered in the bore? If it is, shim or Zee. If not, you have issues that will haunt you as long as you own it.

YMMV, but I don't label these as keepers.

Surprising from Savage, I though Remington had the exclusive on this.

 

[Ruger007]

I looked down the barrel. Firing pin looks centered. I'm past the warranty for the gun. Savage says 1 year.

Will try a shim.

 

[Ruger007]

So here is my math if anyone wants to try it. Or i am wrong let me know.
Distance between rings = A. 4.3"
Distance to move at 100yds = B 24moa
1"= 1moa at 100yds. Or 3600"
.25"=1moa at 25yds.
Need to move approx 6" at 25yds. 6÷.25= 24moa.
(AXB)÷3600
(4.3X24)= 103.2
103.2÷3600= .0286666" of shim

Pop can is .005" so i will add five layers.
Added a shim on the back screw on the front to help with angle. Also added an extra on the back. 4 on the front back screw and 5 on the back, back screw.

Seems like alot but we will see tomorrow.

 

[Dogleg]

Rule of thumb is .001” of shim for 1” adjustment at 100 yards; so your math passes the “logic test”.

I’d rather see a single shim than a stack of five though.