I have a Nightforce 8-32 X 56 NXS scope mounted on a new Remington 700 VS .308 with the Badger Ordinance 20 moa 1-piece mount. I have to dial up the elevation in the scope 30 moa just to be able to zero the rifle at 100 yards. I run out of elevation adjustment before I get to 1000 yards.

Should I consider trying the Nightforce 40 moa 1-piece mount? If my thinking is correct, an additional 20 moa cant in a different scope mount would allow me to drop my scope elevation adjustment from 30 moa down to 10 moa, thereby giving me 20 moa additional adjustment in the scope.

Have any of you run into this problem before? The 8-32 Nightforce permits 65 moa total elevation adjustment. Since my 100 yard zero requires me to use almost half of the 65 moa (30 moa scope elevation adjustment) I run out of adjustability before I get to 1000 yards.

Any comments would certainly be appreciated. Thanks.

Is the base on backwards?

George

Hello nzzytb,

Is it possible that the 20 moa base is on "backwards"? The Objective should be tilted down towards the barrel.

If the the scope adjustments are centered, and the reciever/bore is "straight", the 20moa tapered base should require you to move the elevation down approximately 20 moa for 100 yard zero. If you need 30 moa up from the scope center for a 100 yard zero, something is seriously amiss.

The specs on that scope indicate 65 moa Elevation adjustment, so you probably do need some cant in your scope mount (20 moa SHOULD be plenty). I need 40 moa up from 100 for my 308 - Sierra 190 HPBTs @ 2500 fps.

Regards,

Bill

Have you lapped your rings? Check that the scope is sitting in the rings properly. Check that the Base is also fitting your action properly and squarely.

The mount is installed correctly. I lapped the rings with the Sinclair lapping tool. I installed the scope, when to the range, and found my bullet point of impact to be low. I turned the elevation turret to cause the point of impact to rise. This is what I am referring to when I say that I dialed the elevation UP. I had to dial all the way up to 30 moa just to get to zero at 100 yards. Normally, I would have been looking for a 200 yard zero, but I suspected I would run out of elevation adjustment if I zeroed at 200. I found that I needed an additional 52 moa to get out to 1000 yards. That equates to 20 moa from the mount, plus 30 moa adjustment of the scope to zero at 100 yards, plus 52 moa additional to hit the 20" by 40" steel silloette at 1000 yards. Since the scope only allows 65 moa total adjustment, I had to gain the additional 20 moa by using the elevation increments provided by the NP-R2 reticle, which, by the way, works great.

I speculated that if I were to replace the 20 moa scope mount with a 40 moa mount, then I would be able to dial my 100 yard zero back down to 10 moa which would leave me with 55 moa to get to 1000 yards without using the additional elevation provided in the reticle.

I thought I would run this by all of you to make sure I wasn't missing something.

I don't have a chronograph to check to see if my hand loads are slow. I do seat my bullets to within .010" of the rifling. This results in an increase of .110" over the 2.800" measurement to fit most factory magazines. I load one round at a time. I'm shooting the 168 grain Sierra Match Kings with 42.0 grains of RE 15. I will try the 175's next, but it looked to me like I needed more cant built into my scope mount before I went any further.

Have any of you noticed an appreciable decrease in velocity as a result of seating bullets out to touch the rifling. I realize .110" is a long way out, but that is what the factory chamber requires.

Any thoughts or comments are greatly appreciated.

Is it possible that the scope's elevation was bottomed out, and you've just brought it back to mid-range?

Have you checked how many MOA upward adjustment is left in the scope?

George

I still wonder if the base was installed correctly? Or did you install something incorrectly machined or labeled? Did you measure the bases with a micrometer yourself to verify the thickness? When loctite was applied to the base mount, did it harden prematurely and raise the front base higher than the rear thus reversing the intended effect of the 20 MOA base? Is there a machining defect in the receiver/action that causes the opposite effect you intend?

I suggest that you adjust the scope through its full range and set it 15-20 MOA up from its lowest setting.

Then remove the bases from the receiver/action. Check to see the loctite has not interfered with the mount. Remove the material and retap if necessary to ensure a proper installation.

Cut some aluminum can tabs and place these under the rear base between the base and the receiver/action. The top of the can or the sides can be used. Try a single thickness of the top here, it is thicker. Distribute the aluminum evenly with a large enough piece to ensure enough contact. Retighten the base and torque properly after installing fresh loctite.

Leave the gun outside or in a cold location over night and retorque in 24 hrs.

Shims are also available from Sinclair International. The same trick works for windage too. I use this procedure all the time when I mount Mark 4 scopes as they have only 30 MOA of windage and I need them centered as well as possible.

Good luck.

[ 04-24-2003, 15:54: Message edited by: sy308 ]