Rifle Scopes Tips to "Safely" Reset NightForce Zero Stop?

[ICanSeeYourPixels]

Morning! A few weeks ago I shot a match, and had a ~0.2-0.3 shift in my zero when I verified it at the start of the match. I corrected it, and went to reset my zero stop prior to the start of the first stage.

I gave 0 thought to holding that turret still, and when I turned the first screw to back it out I spun the dial and completely lost my zero. Hindsight is 20-20, and holding my thumb on it as I loosened the screws is a quick and easy fix solution. However the damage was done and I had to completely re-zero the elevation.

I was curious - are there any redundancies or tricks you use to protect against this, or to more quickly recover in an instance this happens?

 

[Trigger Monkey]

The NF manuals tell you to hold the turret while loosening the set screws.

 

[Rodney65]

The best trick I have used to safeguard against this, and it may not work with every scope, is to dial your elevation until it tops out. If you have something like 20.0 mil available if you adjust your zero up 0.3 there should now be that much less elevation travel available and it will now max out at 19.7 mil.

This is something you can check and write down in a data book. It may not be perfect with a zero landing on a half click or what have you. Also I think some scopes only dial a fixed amoubt above their zero stop but in most cases it will get you to within one "click."

Also by doing this you know how much elevation you can dial in the event you are considering adding a sloped base, send your scope for servicing, a turret cap comes loose, or you have a ridiculously long shot to take where you might max out elevation and have to hold over.

 

[ICanSeeYourPixels]

The best trick I have used to safeguard against this, and it may not work with every scope, is to dial your elevation until it tops out. If you have something like 20.0 mil available if you adjust your zero up 0.3 there should now be that much less elevation travel available and it will now max out at 19.7 mil.

This is something you can check and write down in a data book. It may not be perfect with a zero landing on a half click or what have you. Also I think some scopes only dial a fixed amoubt above their zero stop but in most cases it will get you to within one "click."

Also by doing this you know how much elevation you can dial in the event you are considering adding a sloped base, send your scope for servicing, a turret cap comes loose, or you have a ridiculously long shot to take where you might max out elevation and have to hold over.

That's a clever idea. Almost like maintaining a "zero" value from the top of the range.

That would have for sure helped in this situation to at least be in the ball-park resetting.

 

[NateVA]

Any idea on the culprit for the shift?

 

[Ronws]

I had learned that going to the top and then back down to half the total range gets you a mechanical zero. It may not be the actual zero for your rifle but it gets you close enough to bore sight and start over again.

 

[ICanSeeYourPixels]

Any idea on the culprit for the shift?

Went through a bunch of ideas in my head. Velocities were within 5fps of one other. It was raining when I zeroed originally, 95deg and sunny when I shot again. Internet seems to say that that shouldn't impact a 100yd zero.

My primary thought is maybe the slope difference in ranges? I'd need to measure it, but my home range is at a slight downward angle and where the match was was fairly flat. Other than that, the tool behind the tool is always a solid guess lol.

 

[JayOpticspecialist]

I've never had issue holding while i engage the zero stop. depending on the scope. Guess you just have to rezero, I would for piece of mind anyway. on the older scopes, you used to be able to hold it with an allen wrench or screw driver while setting the zero stop. on the poi shift, probably obvious and might be silly mentioning it, but was your barrel hot? don't here it's hard to zero and shoot groups because barrels get hot quick then take forever to cool down because of the humidity.

 

[NateVA]

Other than that, the tool behind the tool is always a solid guess lol.

Always possible. I kind of doubt it's the scope but there are always other factors. Is the rifle in a chassis or stock, and is it bedded? It's seemingly become a topic of discussion on whether certain chassis benefit from bedding. The owner of MPA, for instance, says MPA chassis benefit from bedding specifically in regards to zero-shift.

Then there are the rings and any possible loose screws I guess. Who knows though, probably worth looking into if it happens a second time.