Reducing The G force on a scope in both directions on a Diana 54

[Poor Ballistics]

Hello to all:   I recently purchased a Diana 54,  and as with all the sledge type systems, even harder on scopes than regular springers. 

Not wanting to eat my scope,  I  came up with a solution somewhat different from the Diana Zero recoil mount, but accomplishing the same goal.   I am probably not the first one to do something like this, so if anyone has any information about this approach to saving the scope, please let us know. 

BKL makes an extruded one piece mount whose base slides onto the rails. There are no removable side plates, if it does not slide on, you have to use the  supplied set of special screws to expand it.  Perfect for what I wanted to accomplish.

Using the 220 grit lapping paste from my scope ring lapping kit, I lapped in the BKL mount to the rails, (if anyone is interested I could add pictures and go into details of the lapping) .  Prior to lapping, I taped off everything except the rails, and after lapping and cleaning  I lubed and tensioned the screws so that when fired the scope and mount moves forward 1/4 of an inch relative to the rails.  There is absolutely no side or vertical  play when I apply force to both ends of the scope.  I could back off on the screws slightly, and the scope/mount would  still have no play, but I did not want the scope/mount  to be sliding back an forth to easily when moving around with the rifle.

I clamped a rail mounted level at the rear of the rail to act as a stop and the scope to be reset to after each shot.  Someday I may add a spring, but for now, when I cock the rifle with some vertical angle, it slides back into position and because of the way I lapped it, there is a bit of stiction the last 1/32 of an inch that holds the scope/mount in place for bench shooting purposes.   I put a stop  at the front of the rail as insurance, though with the slight stiction is almost not needed.  I am pretty sure that I have minimized the g forces in both directions considerably without affecting accuracy.  LONG LIVE THE SCOPE !!!   

[Yogi]

What scope is mounted on your rig?

-Y

[Poor Ballistics]

Hi Yogi,
At the moment I have a  Leapers Accu Shot  fixed 10 power from 2016 I had on my .30 caliber / arrow  FS  Independence  (which is going to be put up for sale  soon) I have an Arken LH-4 6-24x50 FFP | Capped Tool-less Turrets  on the way.   The leapers supposedly are built to withstand the two way recoil of a springer,  not sure about the Arken.   I just found out recently about Arken,  they are worth looking into.   I am getting this scope just to test the accuracy,  it will be on only  for a short while.

I really prefer peep sights, and will soon  be mounting the front globe and  rear peep from my Anschutz  250.  Bless the designers of  Anschutz in the 60's,  the front globe is screwed on, so an easy job to drill and tap the removable aluminum barrel tuning weight designed by Hector.   By the way, if anyone knows where to source the inserts for that vintage of an Anschutz front sight, please let me know. 

[JPSAXNC]

I thought the sledge system on the 54 was supposed the gun recoilless ?

[H95Kidd]

Hello to all:   I recently purchased a Diana 54,  and as with all the sledge type systems, even harder on scopes than regular springers. 

Not wanting to eat my scope,  I  came up with a solution somewhat different from the Diana Zero recoil mount, but accomplishing the same goal.   I am probably not the first one to do something like this, so if anyone has any information about this approach to saving the scope, please let us know. 

BKL makes an extruded one piece mount whose base slides onto the rails. There are no removable side plates, if it does not slide on, you have to use the  supplied set of special screws to expand it.  Perfect for what I wanted to accomplish.

Using the 220 grit lapping paste from my scope ring lapping kit, I lapped in the BKL mount to the rails, (if anyone is interested I could add pictures and go into details of the lapping) .  Prior to lapping, I taped off everything except the rails, and after lapping and cleaning  I lubed and tensioned the screws so that when fired the scope and mount moves forward 1/4 of an inch relative to the rails.  There is absolutely no side or vertical  play when I apply force to both ends of the scope.  I could back off on the screws slightly, and the scope/mount would  still have no play, but I did not want the scope/mount  to be sliding back an forth to easily when moving around with the rifle.

I clamped a rail mounted level at the rear of the rail to act as a stop and the scope to be reset to after each shot.  Someday I may add a spring, but for now, when I cock the rifle with some vertical angle, it slides back into position and because of the way I lapped it, there is a bit of stiction the last 1/32 of an inch that holds the scope/mount in place for bench shooting purposes.   I put a stop  at the front of the rail as insurance, though with the slight stiction is almost not needed.  I am pretty sure that I have minimized the g forces in both directions considerably without affecting accuracy.  LONG LIVE THE SCOPE !!!

In this setup, exactly where is the movement taking place? I hope you don't have the mount sliding back/forth on the actual dovetail cuts in the receiver! Please explain this in a bit more detail. Please forgive my ignorance, but I'm having a bit of trouble envisioning exactly what you are doing here (where is the sliding taking place?). A pic or two would be nice for us more visual types. Also, I fear that the "slight stiction" you mention will quickly become NO stiction after many shot cycles, and will therefore need constant adjustment to control the friction component relative to the rails.

[Motorhead]

I don't like ANY optics mounting to move .. PERIOD
If you don't want the Diana 54/56 to beat up your optics .. SHOOT IT with the supplied iron sights !!

Convinced you need optics ? .... Then purchase a scope that is Spring gun rated and has a no time limit life time warranty ... shoot it without worry 

[tripiy]

My RWS 48 came with fixed 4x RWS scope. It worked well for around 2 years when it developed condensation around the edge(It had still held the zero). Umarex, replaced it and the new one worked fine for over a year before i swapped it for peep sight. The scope now sits on Hatsan Mod95 and does the job fine.
The thing that seem to have worked in its favor is probably the one piece RWS Locked Down Scope mount

[Poor Ballistics]

     I am replying to  JPSAXNC,   H95Kidd,   and   Motorhead in that order:

JPSAXNC,  The the sledge system as made first by Feinwerkbau,  then Diana 54 / 56 has the metal bits sliding on a mechanism inside the stock. If you watch slow motion video on YouTube you will see the metal bits sliding first back, then stop (AKA reverse recoil, it is this sudden stopping that kills scopes) as the piston reaches the end of its stroke.   The stock does not move, or at least not much, depends on how much friction is in the system. So, as the shooter,  you do not feel much, but you can see the metal bits move, so it is  recoilless  in the sense of the stock not moving. 

If you take the Diana 48, which does not have the sledge system, the metal bits are securely attached to the stock, and you feel the recoil. In fact, on the 48, the recoil g forces are less on the scope than on the 54 / 56 because of the mass of the stock slows things down a bit.  The 54 / 56  have a reputation for eating scopes because those g forces. 

There are two sledge type rifles that I know of that are different:  the Anschutz 380 and the recently on the market Norica Omnia, they have the moving metal bits inside a shell.  The 380 is simply elegant and I am in the market for one if anyone has one to sell or trade (I have an FX .30 cal Independence with Arrow barrel that needs a new home).  On these you can mount any type of scope just as you can on all the pneumatic types and not be concerned about the scope holding up. 

H95Kidd: I read in the rules that I need 20 posts before I can post pictures, not sure why, maybe I misread ?  Anyway, go to the BKL website  and check out their 200, 300 and 400  one piece scope mounts.   

The way I have set things up the scope and mount do indeed slide on the rails.  As I said in the original post, I lapped the mount in, and I did it in a very precise way, and the result is  super smooth and zero horizontal or vertical play

The mount is aluminum, and after a certain number of shots the screws may need a smidge more tightening as the aluminum wears,  but because of the lube, not very often.

Motorhead:  Please read my reply to Yogi.

 

[Denby95]

I don't like ANY optics mounting to move .. PERIOD
If you don't want the Diana 54/56 to beat up your optics .. SHOOT IT with the supplied iron sights !!

Convinced you need optics ? .... Then purchase a scope that is Spring gun rated and has a no time limit life time warranty ... shoot it without worry 

Exactly this. It's what I did and I've never had a single problem with a standard mount and Hawke Air Max.

[Poor Ballistics]

Reducing the G forces on scopes:

Ladies and Gentlemen,  AS I SAID IN MY POST,  I did not want to take a chance on killing the scope I have, and the one coming,  I will save those for pneumatics, the  Anschutz 380 or the Norica Omni.  AS I SAID In MY POST,  I will  be putting the peep from my Anschutz 250 on the Diana 54.   I prefer peep sights to scopes,  I use scopes and a bench rest  to test pellets  etc. 

When I have the required 20 posts, I will upload pictures and maybe video of what I did. It works perfectly.  Smooth as butter, absolutely no vertical or horizontal movement when pressure is applied at the ends of the scope.   

It does require me to make sure the mount is pushed back the 1/4 inch after each shot, but other than that no downsides,  all upsides.    This system as with the Diana Bullseye allows you to use any scope you want, not the supposedly "springer rated" scopes.  And, it does not cost much.     There are a tremendous number of scopes to choose from made for the one way recoil of a firearm, and those can be used on any springer if the reverse recoil can be canceled relative to the scope, and my system can cancel the recoil felt by the scope  in both directions.

 So, for those of you that want scopes on your springers,  and want the freedom of choice as to scopes to purchase, try this G force elimination method.    From my research, the Arken scopes are the most scope for the least money at the moment, and that is what I have arriving sometime today. 

[Yogi]

Yes Mark,

But most of those Firearm scopes do not have A/O or the ability to focus down to 10M=/-.

-Yogi

[Poor Ballistics]

Yogi, 

True,  the choices get much more limited  when looking for scopes adjusting down to  10 yards.   The Arken 6x24  that was delivered today adjusts down to 10 yds,  and of course that was a requirement of mine. I would have bought another scope of theirs, but that one only went down to 25 yds. 

[HectorMedina]

I am replying here at Mark's request.

So, let's take a step back:
The FIRST recoil mitigating mounts were the old mounts made for the externally adjustable bench rest scopes. Brands like Bausch & Lomb, Unertl, Litschert, Lyman, Tasco, and the modern replicas by Hi-Lux:



produced amazing scopes with the power that BR shooters demanded but, they could neither guarantee the life of the reticle (remember some reticles were actually made of spider web, some were actually "hairs") nor guarantee the "zero" of a miniaturized version of the adjusting rings of the time being put into 7/8" tubes. The parts were too small and weak for the resistance needed as calibers for BR got more and more powerful (we need to remember that BR was born during the heyday of the Velo-Dog cartridge).

On TOP of that: shooters back then were savvy enough to not TRUST something that was hidden. They wanted to see the scope move.
And on TOP: shooters that trusted scopes knew a thing or two about optics and they KNEW that any optical system taken out of its optical axis was not performing at its top level (back then all lenses were simply spherical).

So, there were MANY reasons to use an externally adjusted scope, and if I may digress a little here, the most sophisticated / most expensive scope currently in production that would remotely have some application to airguns IS an externally adjusted scope:

For a while, US Optics also offered a similar product.

So, fast forward to 2016.
Someone approached DIANA with the idea of "floating" the scope while the piston did its "boinger boogey" thing. I was consulted and I suggested using conical pins instead of the cylindrical pins that are the "rails" where the floating part rides. Needless to say, I went unheeded and the small cone at the front of the ZR Mount remained.
AND, the need to "accurize" the OEM ZR Mounts was born. At least for those that want absolute precision, return to register, AND long term maintenance.

To understand how the ZR Mounts, you should read this:
https://www.ctcustomairguns.com/hectors-airgun-blog/a-high-speed-analysis-of-the-way-the-zr-mounts-work
Pay special attention to the slow motion video and observe it several times, note how the action bounces TWICE, and that the whole mechanism settles to a different point than the points where the back and forth movements changed direction.

And this:
https://www.ctcustomairguns.com/hectors-airgun-blog/march-14th-2016
Note how we use the "tightness" of the fit between dovetail and scope mount to determine if the mount moves or not. IF it had moved, it would have meant that the forces and vibrations of the recoils and the "Sproinger Boogey" were being transmitted through the scope to the mount and from there the movement. But there was none.

And the first part of this:
https://www.ctcustomairguns.com/hectors-airgun-blog/truly-taming-the-harmonics-in-spring-piston-airguns

Where we actually measure with a high end accelerometer the forces and vibrations that "remain" in the system after installing a ZR mount.

Once with all that knowledge, let's get into the subject of the matter:

Mark's solution is NOT a bad one.
On one hand, it prevents the scope from receiving the full brunt of the double recoil.
In a sense, just like the ZR mount, it "floats" the scope along the bore axis, while the piston is doing the "sproinger boogey".

What Mark's solution does not provide is a long term/worry free solution.

The Accurized ZR Mount has two teflon buttons that are installed to eliminate friction in a full contact scenario, while allowing the scope to float in THREE DIMENSIONS (not just one), and then ensures that, without any added effort from the shooter, the scope returns exactly to battery.
The vertical and lateral movements of a spring-piston action have been demonstrated and measured. The "HPM" is a way to control the effects of these in the muzzle's LOF (line of fire), but it cannot do anything for the scope. The vertical and lateral vibrations WILL affect the scope's mechanisms.
At this year's World's in Phoenix, I counted 6 shooters from 3 different countries using Accurized ZR Mounts.

And here is the main point:
Under current manufacturing practices, MOST scopes will withstand a bit of double recoil, some will withstand a lot. But NOTHING defends the scope from vibrations in 3D as to make it "float", and that requires some tolerances between the rails and the floating slide that holds the rings. As well as three very precise "register points" so that the scope can return to battery exactly. Remember three points in space define a plane.

Polishing the dovetail and adjusting the "fit" still does not allow for vertical and lateral movements.

Aluminum on aluminum will also wear out faster than teflon on steel (or in the latest, MkVII version, teflon on bronze). So more maintenance is to be expected.

It is easy to think that we do not want our scopes to move AT ALL. The truth is that, whether we like or not, they move, either for mechanical or thermal reasons.
Question is whether we control the movement, and abate those movements that are noxious to top precision and accuracy, or we let them slide (pun intended).
And, BTW, this is a Hawke scope after a few shots in a D54:

And while you may be lucky, you may not be. In THIS case, Hawke refused to comply with warranty terms.

IF you DO decide to use Mark's strategy of polishing the mount-rail interfase, do get a tube of this:


Because if you ever decide to mount something that you do NOT want it to slide, you will need it.

Keep well and shoot straight!






HM

[Poor Ballistics]

Hector,

Great input all around, much appreciated.  History of older scopes and mounts, deep intel on the ZR mount, just fantastic!   I do not understand allot of what you said, I will spend some high quaility brain time and noodle things out!  (quality brain activity is only the first hour of each day, so it may take awhile!)

My first take away is that  the spring gun world needs an improved ZR mount,  one that does not have to be accurized.

I agree with you about my setup, it is just a temporary solution to a specific need:  I  did this so as to not ruin a new scope.  I am going to install  a rear peep and front globe to the Diana 54,  but I did want to have the ability  to shoot off a bench with a high powered scope and find the best pellet and see how small a group I could get at 25 and 50 yds.  (when there is no wind!  🤓) 

I have a tiny bottle of Beeman Ultra lube from 40 years ago or so, and I coated the rails and all screw threads with that, as I did not want the  steel screws to gall the aluminum threads, or aluminum mount on the steel rails.  I will check out that product you supplied a link to.

Hope Diana or some manufacture will produce and sell the ultimate ZR scope mount for firearms and spring guns.
Any machine shop owners out there?  Please talk to Hector!!

[lefteyeshot]

I've had a 56th for several years, got a ZR mount for it when they first came out and put a 4-12x40 AO mildot Vortex Diamond Back on it. Works for me. It's been awhile but seems the 56th broke a couple of scopes when I first got it. My Hatsan 155 broke more.

Correct me if wrong. As I understand it, with the 56th, I don't feel the recoil, the stock doesn't feel the recoil but the receiver feels it and the scopes on the receiver so it feels it.

[HectorMedina]

I've had a 56th for several years, got a ZR mount for it when they first came out and put a 4-12x40 AO mildot Vortex Diamond Back on it. Works for me. It's been awhile but seems the 56th broke a couple of scopes when I first got it. My Hatsan 155 broke more.

Correct me if wrong. As I understand it, with the 56th, I don't feel the recoil, the stock doesn't feel the recoil but the receiver feels it and the scopes on the receiver so it feels it.

You're right Tim.
The 56 T/H is just a 54 in a more elegant stock (thanks to Martin Zedler, then acting CEO of M&G/DIANA).
Apart from the stock, the barrel shim and sleever, and the muzzle piece, all other parts are indentical.

When a shot is fired in a "conventional" piston airgun, the MASSES of the shooter's arms, and torso are added to the mass of the stock (even with the most careful artillery hold) and mechanisms tube.
This total mass is, then, the "resisting mass" to the acceleration provided by the movement of the piston and spring.

In a 54/56 you cannot add the arms, torso, stock to the mass of the receiver. Therefore the "resisting mass" has just been decreased substantially. And the full "brunt" of the piston's movements is felt directly by the scope and the mechanisms tube.

HTH, keep well and shoot straight!



HM

[HectorMedina]

Hector,

Great input all around, much appreciated.  History of older scopes and mounts, deep intel on the ZR mount, just fantastic!   I do not understand allot of what you said, I will spend some high quaility brain time and noodle things out!  (quality brain activity is only the first hour of each day, so it may take awhile!)

My first take away is that  the spring gun world needs an improved ZR mount,  one that does not have to be accurized.

I agree with you about my setup, it is just a temporary solution to a specific need:  I  did this so as to not ruin a new scope.  I am going to install  a rear peep and front globe to the Diana 54,  but I did want to have the ability  to shoot off a bench with a high powered scope and find the best pellet and see how small a group I could get at 25 and 50 yds.  (when there is no wind!  🤓) 

I have a tiny bottle of Beeman Ultra lube from 40 years ago or so, and I coated the rails and all screw threads with that, as I did not want the  steel screws to gall the aluminum threads, or aluminum mount on the steel rails.  I will check out that product you supplied a link to.

Hope Diana or some manufacture will produce and sell the ultimate ZR scope mount for firearms and spring guns.
Any machine shop owners out there?  Please talk to Hector!!

My pleasure!

I do offer the Accurized mount. I've sold well over a couple of hundred.

IF M&G wanted to  issue the Accurized mount as OEM, they could, I've offered them the technology several times.
BUT the price of the mount would go up substantially, and so they do not feel that the BULK of the airgun market needs it.

If you want an Accurized ZR mount, let me know, they are built on order, so it takes time.

;-)

Keep well and shoot straight!





HM

[Poor Ballistics]

Hector,

I do want an Accurized ZR mount, will PM you.

I am still reading  all you have written and watching  the  videos.   

By the way,  your  tip about friction drops:   I checked that out.  How did I go through so many years, researched so many things, especially allot of machining videos,  (I have a mill, a lathe, all the precision tools, just the machinist is weak link) and not know about this kind of product?  It  makes so much sense,  I could have used it many times in the past.