RWS Bullseye ZR (Zero Recoil) Mounts and Improvement

A few have recently asked how I maintain good accuracy using the RWS ZR Bullseye (and clone) mounts. I take no credit for this method. I initially saw these being made by Hector Medina, and his are much more finely executed. 



Here is what I have done to eliminate the slop in the mechanism. Basic home jobber hackery. The pictures are in no particular order. I used a drill press but it can easily be done with a hand drill as well. It sounds odd but I tap the holes with a metric tap and use imperial nylon bolts. This creates an intentional cross thread. It only deforms the sacrificial plastic bolt and ensures they won't back out. I have MANY rounds on a few of these and have never needed to re-adjust them thus far. I tighten the bolt until it just begins to bind on the slide and then back it out until the mechanism moves freely without any remaining slop then cut off the excess of the bolt with a utility knife or razor blade. One bolt can do all 4 holes. One corner is probably enough but I usually do them on all 4 of the rear corners like this one shows while I have it apart. I have seen others do this to both ends but in my usage, I have found there is no need to do this to the front since the front is located by a conical sleeve and post which is very repeatable even if you feel movement. While I have them apart I usually polish the rods and the inside of the bores just to make it all run more smoothly. These will absolutely allow you to run a fragile scope on a magnum springer without damage. I have never hurt a scope using this method and I haven't heard of anyone who has. 

The biggest issue with these is that there is not much room between the top of this mount and the bottom of the rings. Not all scopes will fit. Any scope with a large under belly or a large nitrogen fill nipple under the turret housing will interfere. These are nothing special and the cheap ones from amazon or eBay are just as good/bad as the official units. Unfortunately, I have found no other commercially available solution available. Be aware I have had to lap the rings in order to get a good fit even on new units. You may be better off buying 2 and swapping parts as needed just in case.

It really is a shame that we have to re-work brand new mounts just to make them serviceable. I would love to see someone on here create a sliding intermediate mount. Dovetail on the bottom to fit our springers and Picatinny on the top to fit the most common rings/mounts. I know we have many machinists here and this is certainly needed. I would think that a person could sell as many as they chose to make at a price commensurate with the quality of the unit/materials.

IMG_1244.1609443079.JPG


IMG_1258.1609443081.JPG


IMG_1259.1609443083.JPG


IMG_1260.1609443084.JPG


IMG_1261.1609443086.JPG


IMG_1262.1609443087.JPG


IMG_1263.1609443088.JPG

 
Nice mod that is for sure. Yes it is a shame that we have to modify so many fairly well designed parts to make them werq as they were designed to. I was lucky one of mine has no perceivable slop and the other one is tight when it is at rest. Which is all that really counts. So I have as yet not had to do this mod.

If you mount has slop in it when in it's resting position this is a great mod. Have you tried a single screw towards the middle of the mount? I would think that that would be all that is really needed. Although what you have done is a far more precise way of doing things.
 
Nice mod that is for sure. Yes it is a shame that we have to modify so many fairly well designed parts to make them werq as they were designed to. I was lucky one of mine has no perceivable slop and the other one is tight when it is at rest. Which is all that really counts. So I have as yet not had to do this mod.

If you mount has slop in it when in it's resting position this is a great mod. Have you tried a single screw towards the middle of the mount? I would think that that would be all that is really needed. Although what you have done is a far more precise way of doing things.

I am sure you are correct. Even with quite a bit of slop, there is usually no effect on accuracy. As you pointed out, if it returns to the same resting position you are good. I have taken one that has a TON of slop and placed it on a rail secured in a vice, after tapping gently and eventually not so gently the scope in the mount returns to zero every time anyway. This sure makes me more confident though. On second thought, maybe I shouldn't be doing this, I am always looking for something to blame my missed shots on!
 
Last edited:
This might be a better product if you have a scope saddle that won't fit into these anti-recoil mounts. It's spendy at around $70. I'm very tempted to try one. Anyone has experience with this riser?


Pair that with a Burris signature zee ring adjustable mount ...


to optically centered your scope and it should be a winning scope mount system for most recoiling springer.
 
Last edited:
By most accounts, the 1st generation ZR mounts were made by Diana themselves in Germany, had slop issues and what prompted the fixes Lewis detailed above in his post. You'll have to do a search here, but there's another thread from back more than a bit ago that details the same thing.
The 2nd generation ZR's (the box even says New Version), were made in China and the one I have. Has a Made in China sticker on the bottom. Mine, like biohazard's, has no perceivable slop and why I haven't tinkered with it. I also have a pair from a company called Mizugiwa that have none either and they even have a version to fit a pic rail:
Jury is still out at least in my case, but so far, I haven't had any problems with either the real one or the clone.
 
I have a Bullseye mount and yes it does have some play, but even with it there is absolutely no need to do any modifications to eliminate it because it ABSOLUTELY DOES NOT affect accuracy. How so? It’s because the conical metal guide slots back and orients the scope to its original, exact position after every shot cycle. Those two—conical guide and hole—are the reason for maintaining POI.

Come on now, folks. Quit doing unnecessary mods to a well-designed and -functioning mount that actually does as intended.
 
  • Like
Reactions: (F)Airgunner
I have a Bullseye mount and yes it does have some play, but even with it there is absolutely no need to do any modifications to eliminate it because it ABSOLUTELY DOES NOT affect accuracy. How so? It’s because the conical metal guide slots back and orients the scope to its original, exact position after every shot cycle. Those two—conical guide and hole—are the reason for maintaining POI.

Come on now, folks. Quit doing unnecessary mods to a well-designed and -functioning mount that actually does as intended.
Biggest question I have, does it save scopes?
 
Nice mod that is for sure. Yes it is a shame that we have to modify so many fairly well designed parts to make them werq as they were designed to. I was lucky one of mine has no perceivable slop and the other one is tight when it is at rest. Which is all that really counts. So I have as yet not had to do this mod.

If you mount has slop in it when in it's resting position this is a great mod. Have you tried a single screw towards the middle of the mount? I would think that that would be all that is really needed. Although what you have done is a far more precise way of doing things.
Did you mean like this?

17140578803391254428205498046957.jpg


17140579230594904867460674075696.jpg