Odd Scope Question.

I have an odd question for you folks.

I had a Nikon PROSTAFF P3 TARGET EFR 3-9x40AO PRECISION scope on our Weihrauch HW97-K underlever spring piston air rifle.

This scope would work fine for a while, and then the POI would abruptly drop 2" and 1 1/4" to the right. I'd re-zero the scope. It'd work fine for a while again, and then would abruptly drop down and to the right the same amount again. This happened several times, until there was no longer any elevation adjustment left.

I sent it in to Nikon to see if they'd repair or replace it under warranty.

In the meantime, I had a new in the box Weihrauch 3-9x40 scope sitting around unused. I mounted it on the rifle using SportsMatch medium scope rings. And keep in mind, these are not the same rings I was using with the Nikon scope.

I went to sight it in at 20 yards, and even with the elevation adjusted all the way up, minus a few clicks, the POI is still 1 1/4" low.

Do any of you have any idea what is going on here? This is not a break barrel.

Do I need a droop compensator mount?

Would a Bullseye ZR-mount help?

Have any of you even heard of a problem like this with an HW97-K?

I don't know what to make of this!


 
I have a scope on one of my air rifles that is not able to lift the pellet's POI any higher - my pellets are hitting about 2-3 inches below the bullseye, dead center, just low. I thought about shimming the back ring or using a droop mount, but instead, bought this set of adjustable rings tonight. I'll be getting them in a few days.

Looking forward to trying them out.

https://www.amazon.com/gp/product/B07L4ZT7CT/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1


 
Scope mount or a slightly crooked barrel could be the issue. Dont fight it, go to a fully adjustable mount! Use one on my R 1. For years never moved! Center your scope before mounting always....never go beyond one full turn on any scope dial or the internals can be damaged..if you cant O within one turn adjust the mount. Many scopes are damaged by going beyond one full turn. All scope mfgrs recomend not going beyond one full turn to O there scope!

The sportsmatch fully adjustable one pc mount is an excellent choice. After all the money spent on a good rifle and scope, dont go cheap on the mounts!!
 
Well, I looked up on the internet how to shim a scope. I'd never done that. I gave it a try, and it looks like it brought the elevation adjustment down just above the mid-point. So it's probably going to solve the immediate issue.

I ran out of daylight, so I wasn't able to get it zeroed quite as precisely as I'd like.

I'm still thinking about the Bullseye or some other compensating mount.

@AirShot, I appreciate what you said about never turning them more than one turn; but it's a little late now! Oops. Next time...

Overall, thanks, guys. All of you!


 
If your guns are shooting LOW you should shim the front rings, not the back, to bring the poi UP. OK, Centercut just texted me to tell me I'm wrong about this. IN MY EXPERIENCE when I've run out of adjustment & still shooting LOW I've always shimmied the front. It's worked for me.. ymmv (I have dovetail rails, not pic) I'm wrong, DISREGARD (WOW, never been wrong before! )
 
If your guns are shooting LOW you should shim the front rings, not the back, to bring the poi UP. OK, Centercut just texted me to tell me I'm wrong about this. IN MY EXPERIENCE when I've run out of adjustment & still shooting LOW I've always shimmied the front. It's worked for me.. ymmv (I have dovetail rails, not pic) I'm wrong, DISREGARD (WOW, never been wrong before! )

Yep, you are wrong about that. And I'd bet all the money in my pocket that it IS the first time. As well as the last, right?
 
After destroying several scopes I put the Bullseye mounts on both of my springers and have not had any problems since. I think they are the answer to your problems. They are droop compensated as well.

Yes, you would want to raise the back of the scope.

My Diana 460 Magnum killed the crap out of a Hawke 3-9x40 Vantage scope. So, I put a Diana Bullseye mount like you mentioned on it and put on another scope. The new scope is doing well, looks like the Bullseye is working.

My Air Arms TX200 and Diana Model 48 springers still have regular mounts on them and their Vantage scopes are doing well, also.