Please help with NFORCE NSX Set-up

[Mikeir96]

Thank you for taking time to help answer this question. I'm new to Nightforce and ballistic turrets. I have a Zero Stop NXS on top of a 300 Win Mag. Had it all built/rigged by Gunsmith. I laser bore sighted it (to try to avoid wasting rounds), and took it to the range today.

I Zero'd it at 100 to take complete advantage of the turret system. Came home to set the Zero stop, and found I can't do it because to get Zero at 100, required the turret to be turned up high, past the 2nd turret ring. Is that normal?

I came back home and turned the turret all the way down to where it was seated just above the 1st turret ring, and put the laser bore sight device in, and, have confirmed that in order for the rifle to be Zero'd at 100, I would have to spin the turret all the way up high again, past the 2nd turret ring. When it is that high, you can't set the Zero Stop because the set screws on the turret cover are too high to tighten the cap on, after the upper clutch face is turned down against the lower clutch face.

Could it be that my scope is mounted too low? I did as much on-line research as I could to try and find an answer, but came up empty handed. Any advise is appreciated very much.

 

[Broz]

With a zero cant rail or standard rings and bases you should have 50 moa up and 50 moa down. If you are at the end of your adjustment it is one of two things.

Wrong bases or a canted rail installed backwards. The thickest end is to be mounted closest to the shooter.

I am not following your description well ( second ring??)

Once zeroed, remove turret knob by loosening two set screws and pulling up. Then loosen 4 clutch screws just enough you can rotate zero stop clutch. Rotate clutch clockwise until it stops and tighten it. Reinstall turret knob.

If you can not do this for any reason something is wrong with base , rings or the scope is broken. But I have never seen a NXS fail and I have been around plenty of them.

Jeff

 

[Mikeir96]

Thank you so much Jeff for taking a stab at answering my question. My explanation was a little confusing so I will try to re-word it with hopes that it makes a little better sense.

I had all the components of my weapon, including the scope, assembled by a Gunsmith. Nightforce rings were used on standard bases that his shop supplied, (and i confirmed the "thicker" base is closest to the shooter), and he fired the weapon providing me with a target demonstrating less than 1/4 MOA 3 shot group at 100 yards.

When I took the rifle to the range myself, (after double checking his work with my laser bore sight, which did not require me to make any adjustments), I also shot a strong 3 shot group, dead on bulls eye. It was now time to set the Zero Stop, so I came home to set the Zero Stop.

I pulled out the instruction sheet as to setting the Zero Stop and followed the instructions exactly. When it came time, however, to put the turret cover back on, I could not screw the set screws to hold the cover on, because INTERNALLY (under neath the turret cover) above the Zero Stop clutch and below the top of the turret cover, there was a void; open space that could not be closed no matter how hard (within reason obviously) I tried to push the cover down any further. I therefore put everything back to normal and tried to run through the exact same process again, only to find the same exact thing was happening over and over again.

In looking at things, I soon realized that the only way to zero the scope in, (as it was assembled by the Gunsmith), is if the turret is turned up so high, that you can see at least 2, closer to 3 REVOLUTION LINES below the turret cap. I'm talking about the horizontal revolution lines that go around the turret body, that get exposed more and more the further up the turret cap is turned. In my case, since i have the new NXS, It looks like I have only 4 of those lines, and they are labeled 1-4.

My thinking is that zeroing in at 100, that being my Zero Stop point, means my turret shouldn't have to be turned up so very high. If that is the case, then am I not losing all the scoping range BELOW that 2nd or 3rd Revolution Line since my zero would be stopped at the 2nd or 3rd revolution ring?

 

[Broz]

I think I got it now. Here is the deal. With a zero cant, also known as a zero MOA or standard rail / mount. Your scope should zero at 100 yards close to the middle of your elevation travel. This equates on your scope to 50 moa of dial up elevation and 50 moa of down adjustment. That 50 down will not be used with your current scope base if it is indeed a standard, 0 moa. mount. If you want to be closer to your #1 line, or zero line on that scale, you will need to change your rail mount out for a 40 MOA canted rail. Or a 20 moa would also get you closer if your existing rail is indeed a zero moa or standard rail / mount.

That said with your current set up you should have at least somewhere around 50 moa of elevation adjustment. That will get many rifles to 1500 plus yards. What caliber and bullet are you using and what is the max distance you intend to use this rifle? Then I can offer some better defined advice to your specific application.

Jeff

 

[Rockfish Dave]

Keep in mind as you move towards the extreme of your vertical adjustment up (dialing for distance) or down (40 MOA canted rail) your field of view, light transmission, and clarity will not be optimal.

As you move to the center of your adjustment the image begins to be optimized.

My personal preference is for more cant in my scope base. There is less of a premium on a crisp clear image up close as there is when shooting longer distances.

Plus with a variable scope you can dial back the magnification to optimize the FOV and light gathering ability of the scope and still be usable when shooting close in.

Hope this helps.

- Dave

 

[Broz]

Dave, I am not doubting this at all. But it makes me want to ask what scopes you use and notice this visual difference in?

I have used zero, 10, 20, 30, 40, and 65 moa rails and have never noticed a difference in the field of view when dialing even within 1 or 2 moa from the end of my elevation travel. At least not in my NXS scopes or ATACR's. A while back I dialed the ATACR to 119 moa for a 2971 yard shot. I noticed no difference in the view and was only a few moa from its max elevation. I am just curious if I am missing something or if it is not as big of an issue with a Nightforce NXS or ATACR?

Thanks
Jeff

 

[Rockfish Dave]

Dave, I am not doubting this at all. But it makes me want to ask what scopes you use and notice this visual difference in?

I have used zero, 10, 20, 30, 40, and 65 moa rails and have never noticed a difference in the field of view when dialing even within 1 or 2 moa from the end of my elevation travel. At least not in my NXS scopes or ATACR's. A while back I dialed the ATACR to 119 moa for a 2971 yard shot. I noticed no difference in the view and was only a few moa from its max elevation. I am just curious if I am missing something or if it is not as big of an issue with a Nightforce NXS or ATACR?

Thanks
Jeff

Hi Jeff,

I had a total of 45 MOA on my SS 5-20. It brought it down to with in 5 MILS of bottoming out the scope with a 100 yard zero.

Although the scope is my favorite for color and sharpness of image (No I do not own a s&b or Hensfolt (sp?), etc.).

Here is a link that we discussed what was happening.

40 MOA base with SS 5-20 - The Optics Talk Forums

At the extreme edge the image on the scope was not as crisp as the image in the center of the viewable image. Then by moving the vertical travel to the extreme limits it only had that to use.

Was it usable at 100? Yes.

Was it as good an image as at the middle of the vertical travel? No.

Did the image improve the further I shot, and hence dialed moving 'up' the erector? Yes. That is why I posted what I did.

Hope that explains my post a little better.

After I get back from shooting I will see if I can find a graphic I came across that really did a good job depicting what I am trying to explain.

- Dave

 

[Broz]

Thank you for the explanation Dave. So you saw this in a Super Sniper. Have you ever seen the same reduction or similar in a NF NXS?

Jeff

 

[Mikeir96]

Jeff:

I am shooting a 300 Win Mag; 180 grain Acubond. I can't imagine ever shooting any longer than 1500 yards, so your explanation makes sense. The only problem is, if I were to leave it as is, without changing to a rail, I will never be able to set the Zero stop because of the space that is left on top (internally) over the Zero Stop clutch and the turret cover? Does that sound right?

Funny enough, when I had the weapon put together initially, I HAD a rail on it that I thought added 20 MOA. I took the weapon to my local gunsmith here, and he convinced me that adding that rail was not necessary, and that's why I agreed to allow him to take it off and assemble it with bases alone, and no rail.

Follow me on this and tell me if it sounds right:

If I put that rail back on, it will add the MOA. By adding the MOA, it will allow the turret to be turned down towards the bottom revolution lines. If its turned down to that line, that will eliminate the INTERNAL space when I put the cap back on, and will allow the cap nuts to make contact with the Zero Stop clutch, as opposed to simply turning and turning and turning into the empty INTERNAL space and making contact with nothing. Does that sound right?

 

[Broz]

You are doing something wrong or something is out of whack. You should not be having the issue you are having.

Lets start from the beginning.

Once you shoot the rifle and have it zeroed on your bullseye at 100 yards. And you remove the turret cover, then loosen the 4 zero stop screws, which direction are you rotating the loosened zero stop clutch? Clock wise or counter clockwise?

Jeff

 

[Broz]

A. Remove elevation turret cap by loosening the two

set screws 1½ to 2 turns. Take care not to remove

the screws entirely or lose them. See Figure 1.

B. Lift the cap upward with a slight twisting motion

to remove it from the body. You should feel slight

resistance. Set the cap aside on a

clean surface.



Note: You should not feel any "clicks" during

twisting motion. If you do, loosen the set screws

an additional ½ turn.

C. You have now exposed the

ZeroStop™ clutch



assembly. Take care to maintain the cleanliness of

the inside of the cap and the clutch area.

D. Loosen each of the four Allen head screws on the



ZeroStop™

clutch assembly 1½ to 2 turns counter



clockwise. DO NOT remove the screws from the

clutch assembly. See Figure 2.

E. To set the

ZeroStop™ clutch assembly, rotate the



upper clutch face downward/clockwise until it is

firmly against the lower clutch face. See Figure 3.

Note: You should not feel any "clicks" or resistance

while making this adjustment.

 

[Broz]

A couple thoughts of what could be wrong.

1: Make sure you are rotating the zero stop clutch down or clock wise till it stops.

2: There should be no clicks while rotating the loosened zero stop clutch.

3: Did you remove the 4 screws from the zero stop clutch completely? You should not do this and it could have caused an issue.

4: Do you have the two screws in the turret cap loosened far enough to allow the cap to go back on? Probably not this but I am tossing all thought out there.

 

[Mikeir96]

Jeff:

Yea, you are running through all the trouble shooting steps I have taken.

I'm staring at it right now and something just came to me...

There are 3 internal parts: 1) Zero Stop Clutch assembly; 2) Upper Clutch Face; 3) Lower Clutch Face. If you read letter E of the instructions, it says "... rotate the upper clutch face downward, clockwise until it stops against the lower clutch face." I have done that over and over again, WITHOUT MOVING THE ZERO STOP CLUTCH ASSEMBLY.

When the cap is put back on, it necessarily has to seat itself on the upper and lower clutch face, and when you turn the set screws on with the cap in place, the set screws are supposed to make contact with the Zero Stop clutch assembly but they cant, because there is empty space inside because for the cap to seat itself on the upper and lower clutch face, it has to travel less distance down, since my 100 yard zero requires the turret to be turned so high up. Am I making sense?

I don't want to violate any forum rules, but if its easier, and your not offended by it, I will gladly call you so we can communicate by voice, if your OK with that.

 

[Broz]

I will send you a pm with my number