need help with scope zeroing problem.

[2sec]

Hi there, I just bought a NightForce NXS 3.5-15x50 scope, Non-zero stop, nor hi-speed turret model. And at the range I zeroed the scope at 100yards, this scope holds zero perfectly, tracking is great.

However, I noticed one thing that when I zero my scope at 100yards, the elevation turret has 6 revolutions already, the maximum revolution is 10, that only gives me 4 more turns, 40MOAs left that I could adjust. So I couldn't engage targets pass 500yards effectively.

[/url]IMG_7529 by 2sec1, on Flickr[/IMG]

Is that normal? Im using a 0MOA base, if I switch to a 20MOA base that would definitely give me more adjustments, but I don't think NF scopes designed like that, those scope should work fine with 0MOA base, am I correct?

Is there anything I missed when zeroing and setting back turret?

pls help~ thanks

 

[2sec]

Oh btw Im using 308win w/ 168gr SMK when I zeroed my scope, is bulletdrop a concern for such problem? I tried 175gr, at 100yards it drops about half inch, that means if I use 175 I would have 1/2MOA more adjustment. But I don't think its the core problem, 1/2MOA more or less isn't that significant.

 

[supernova]

Sounds like an issue with the mounting. Is it a Remington? Did you check for gap under the rear of the base with only the front bolted down? Scope isn't sitting on the rail or barrel at the front? You should have about half your elevation used up plus height above bore plus bullet drop to zero distance. In other words I think your scope is canted upward slightly. And yes, a canted base is a good idea. NF nor any other scope is designed with cant in mind, you add a canted mount if you need it. I would first check that the scope is not contacting the base or rifle and if that checks out, remove the scope and the 2 rear scope base bolts to see if it springs up away from the receiver. If it does then bed it.

*edit* I just noticed its an ADM QD mount on an AI. What scope base is on the AI? And is the ADM mount canted? I think they make a 20 MOA mount.

 

[2sec]

You have good eyes, yes it's an ADM mount on an AI, the ADM mount is 0moa, the base is a standard AI base with 0moa cant. mostly I shoot at targets within 500yards, even tho it max out of elevation adjustment easily, but still could be zeroed with crosshair on target. I tried to shoot at >600yards and all I could do is using my elevation reticle to compensate for bulletdrop, however my reticle is NPR1, nowhere close to what they called the "Christmas tree reticle", so every time I aim at targets at those distances, the windage reticle is far above and is hard to aim, so I want to get my crosshair back to target at those distances. I checked the mounting and it's the way it suppose to be mounted, torqued, I agree with you that 20moa mount should be the solution. If I ever found it I would get my hands on it.

Thanks for the reply, greatly appreciate it!

 

[ultimate_monkey]

generally speaking, if you want to push way out, then 1/2 of the scopes internal elevation, should be built into your mounting system...

any scope will funtion the best when its mechanically centered (like yours is , right now) but on the flip side you dont have the adjustment to dial for those way out there shots... so with a good rifle (machin work wise) a good rail and good mount, there is no problem to run cant in your mounts. the last scope i mounted and zeroed, i literally was 1 click on my windage off mechanical center, so for me to run 10MILs in my mounting set up isnt a problem

 

[2sec]

generally speaking, if you want to push way out, then 1/2 of the scopes internal elevation, should be built into your mounting system...

any scope will funtion the best when its mechanically centered (like yours is , right now) but on the flip side you dont have the adjustment to dial for those way out there shots... so with a good rifle (machin work wise) a good rail and good mount, there is no problem to run cant in your mounts. the last scope i mounted and zeroed, i literally was 1 click on my windage off mechanical center, so for me to run 10MILs in my mounting set up isnt a problem

When I mount my scope I torqued it to 25in/lbs, and I think it's mechanically centered, because elevation turret is all I dial when zeroing the scope, I didn't touch the windage turret at all. Is it normal to use out half of the internal adjustments to zero a scope at 100yards?

Thanks for reply.

 

[TDC]

40 moa adjustment at 100 equates to 200 moa/inches at 500. That's more than enough adjustment. Keeping your reticle at mechanical centre as mentioned is ideal so a canted base may be your answer.

Tdc

 

[ultimate_monkey]

40 moa adjustment at 100 equates to 200 moa/inches at 500. That's more than enough adjustment. Keeping your reticle at mechanical centre as mentioned is ideal so a canted base may be your answer.

Tdc

No, 1 MOA at 100 is still 1 MOA at 500.. while the over all measurement changes per distance, IE 1MOA is 1" at 100, 2 @ 200, 3@300 and so on... 1MOA is always going to be 1 MOA... While i know what you meant, some one new reading this might get confused by miss use of the terminology..

When I mount my scope I torqued it to 25in/lbs, and I think it's mechanically centered, because elevation turret is all I dial when zeroing the scope, I didn't touch the windage turret at all. Is it normal to use out half of the internal adjustments to zero a scope at 100yards?

Thanks for reply.

I mean "perfect" function when mechanically centered in both windage and elevation.. which you are close too... think about it this way.. your scope has (IIRC) 110 MOA of internal adjustment. thats 55up and 55down, you havnt used 1/2 your elevation to get your zero, youve only used 15MOA... which leaves the scope pretty damn close to mechanical center, which is how it was designed.. there is nothing wrong with your scope. and chances are nothing wrong with your mounting set up, its just not what you want...

 

[Ganderite]

If you want to shoot long range, use the 175, not the 168. It is the same bullet with a better boattail.

If you have 40 minutes of up left on the scope, that is enough for 1000 yards.

However, if I was building the rifle, I would use a 20 minute base, so as to not waste all that elevation. I don't like to use scopes near the limit of movement.

Burris makes a good ring that has inserts that allow you to shift elevation. You want to point the scope down.

 

[supernova]

Another way to look at it is at what distance would you like your scope mechanically centered? If you only shoot a couple hundred yds then this setup is fine, however to push it out there you are topping the scope out before reaching your desired distance. The OP's issue is running out of elevation for the distance he wants to shoot. I'm not familiar with AI bases but ADM makes plenty of canted mounts in 20, 30, and 40 MOA. You could sell yours and buy the same mount but canted. Problemo solved.

 

[TDC]

No, 1 MOA at 100 is still 1 MOA at 500.. while the over all measurement changes per distance, IE 1MOA is 1" at 100, 2 @ 200, 3@300 and so on... 1MOA is always going to be 1 MOA... While i know what you meant, some one new reading this might get confused by miss use of the terminology..




I mean "perfect" function when mechanically centered in both windage and elevation.. which you are close too... think about it this way.. your scope has (IIRC) 110 MOA of internal adjustment. thats 55up and 55down, you havnt used 1/2 your elevation to get your zero, youve only used 15MOA... which leaves the scope pretty damn close to mechanical center, which is how it was designed.. there is nothing wrong with your scope. and chances are nothing wrong with your mounting set up, its just not what you want...

I see your point, thanks for keeping that clear for those who I may have confused.

Tdc

 

[2sec]

No, 1 MOA at 100 is still 1 MOA at 500.. while the over all measurement changes per distance, IE 1MOA is 1" at 100, 2 @ 200, 3@300 and so on... 1MOA is always going to be 1 MOA... While i know what you meant, some one new reading this might get confused by miss use of the terminology..




I mean "perfect" function when mechanically centered in both windage and elevation.. which you are close too... think about it this way.. your scope has (IIRC) 110 MOA of internal adjustment. thats 55up and 55down, you havnt used 1/2 your elevation to get your zero, youve only used 15MOA... which leaves the scope pretty damn close to mechanical center, which is how it was designed.. there is nothing wrong with your scope. and chances are nothing wrong with your mounting set up, its just not what you want...

I have 100moa of internal elevation adjustments, and I used 50moa(5 turns, 10moa per turn) to get to my zero, for my windage I have 80moa of internal adjustments, I used 40moa of them, so my elevation/windage=50%/50%, would it still be considered as machanically centered?

 

[2sec]

If you want to shoot long range, use the 175, not the 168. It is the same bullet with a better boattail.

If you have 40 minutes of up left on the scope, that is enough for 1000 yards.

However, if I was building the rifle, I would use a 20 minute base, so as to not waste all that elevation. I don't like to use scopes near the limit of movement.

Burris makes a good ring that has inserts that allow you to shift elevation. You want to point the scope down.

Another way to look at it is at what distance would you like your scope mechanically centered? If you only shoot a couple hundred yds then this setup is fine, however to push it out there you are topping the scope out before reaching your desired distance. The OP's issue is running out of elevation for the distance he wants to shoot. I'm not familiar with AI bases but ADM makes plenty of canted mounts in 20, 30, and 40 MOA. You could sell yours and buy the same mount but canted. Problemo solved.

The rifle was purchased used, so the setting is already there, not something that I could change, and AI parts are hard to find, but I agree with you of the mounting solution, I found myself a pretty good ADM 20moa mount, now my scope has 60moa of freedom compared to previous 40moa, I'm pretty happy with that. Now all it left to do is my marksman skill to really reach out and touch something.

 

[BigUglyMan]

You ask if it's normal...well, these things happen. I had a 300WM built by ATRS and when I zeroed my 5.5-25x with a 0 MOA rail I had +70 MOA on the scope. The remaining 30 minutes should have gotten me to 1000 but I prefer to work in the middle of the tube rather than out at the top or bottom to allow the windage adjustment plenty of room to move. A quick call to ATRS and a few hours of machine time had me a custom +40 MOA M70 base built and installed. Now I'm zeroed at 100m with 70 MOA still in the scope. All my adjustments out to way far away are made in the middle of the scope rather than getting into the limits of the erector assembly. Ev'rbody happy happy happy.