A high speed analysis of the way the ZR Mounts work

2/9/2015

Some things are too fast for the human eye to see.

If you have been following the development of the ZR mounts by Diana, I am sure you will have seen the VIMEO video that purports to be slow motion.
Well, it is and it isn't. It is a digitally created slow motion. As can be seen from the deformation of the turrets upon firing the rifle (a Diana 54 BTW).
We all know that turrets do not deform, they are too short. Barrels do flex, actions also do, even some scope bodies. But not turrets.

When Hannukkah came around, I subliminally dropped the hint that I needed a high speed camera to capture the action. So, lo and behold, through the generosity of my In-Laws, I now have a Casio Exilim 700.

It is pink. But I do not care. It shoots at 1000 frames per second and while the "movies" are grainy and dark and will definitely win no academy award, they do show EXACTLY what is happening because each frame takes 1 msec (1/1000'th of a second).

The camera also has the ability to take a "picture" of every frame, so that you can display as an image.

Here is a slideshow composed of the 13 msecs that it takes from the moment the sear breaks:

And here is a Youtube version of the film. Displaying at 50 fps while the film was made at 1000 fps:

As you can see, the action starts from a point forward, then the whole action recoils while the mount stays stationary. This takes about 8 ms. By then the pellet is out of the barrel. The action then stops and even moves forward a little bit, the famous forward recoil of all piston airguns.

It is only then that the ZR Mount starts moving to its original place that is indexed with the conical lug at the front of the lower base.

It is important to note that even when the action is stopped and the mount starts moving backwards, you can still see a further movement of the action backwards. This is the extent of the piston re-bound in a CCA WFTF D54, it takes about 1/5 of the overall recoil distance. In a standard D54's this rebound takes about 1/2 of the overall recoil distance.

When using a full power D-54, the distance that the action moves reaches the rear end of the ZR Mount and pulls the scope, thereby negating part of its virtues. But it is still a big help, and as long as you mount a good scope, you will be lengthening the life of the scope by a good amount.

In full power, non-sled actions, the ZR Mount does a better job. And this covers 99% of all spring-piston airguns.

Overall, I think the ZR Mount is a valuable addition to the arsenal of solutions available to the airgunner. While it is not for everyone, it will provide a service to those that like to shoot powerful spring-piston airguns and it opens the options of possible scopes to be used to a wider range of brands and models that would otherwise not be considered.

Keep well and shoot straight!

28 Comments

Alejandro O. Martinez

2/9/2015 12:18:01

"When using a full power D-54, the distance that the action moves reaches the rear end of the ZR Mount and pulls the scope,
thereby negating part of its virtues."
Perhaps what is needed are stronger ZR-Mount reaction springs and/or the addition of synthetic buffers/bumpers to further absorb the greater recoil being generated by a full-power M54. Better yet, consideration should be given by Diana to introduce a second FAC-version.

HECTOR J MEDINA G

2/10/2015 10:16:56

Maybe, Alejandro.

In truth the further development of the ZR Mount will have to wait till Diana is completely reorganized under GSG tutelage.

For the time being, I am told we can expect to get the same lineup of products.

Alejandro O. Martinez

2/14/2015 13:25:54

With respect to the Diana Model 54 ... "When using a full power D-54, the distance that the action moves reaches the rear end of the ZR Mount and pulls the scope, thereby negating part of its virtues." ... does the size and the weight of the scope have an impact on the effectiveness of the ZR-Mount.
And, is there a general-rule-of-thumb you advocate when selecting a telescopic sight to be used on a M54 in-conjunction with a ZR-Mount.
For instance, whenever possible give strong consideration to employ a smaller/lighter scope.

HECTOR J MEDINA G

2/16/2015 05:01:03

Alejandro;

The mainstay for the D54 is the Vortex Optics Diamondback 4-12X40 AO DH/BDC.

It is relatively light, small, very stoutly constructed with excellent glass and has a GENUINELY useful reticle if you want to learn how to use it. It is also a 1" tube, which makes for lower overall profile, and being an AO scope, it can be uncased/cased easily in the field.

The magnification range is also useful for practical purposes. Not so much for FT, but for general shooting and hunting is almost the ideal scope.

Not cheap in any way, and not inexpensive either, but the service it renders is more than commensurate to the price, rendering it an excellent value.

HM

Alejandro O. Martinez

2/16/2015 07:29:21

With respect to the Bullseye ZR-Mount ... is there a general-rule-of-thumb you would advocate when selecting a specific telescopic sight to be used in-conjunction with a ZR-Mount?.
For instance, when determining what a scope to best to be used with the ZR-Mount, are there any size, weight and/or objective diameter limitations to be considered?

Alejandro O. Martinez

2/9/2015 12:26:22

Since Umarex USA is not importing the ZR Mount ... how or where can U.S. airguners buy a ZR Mount in America.

HECTOR J MEDINA G

2/10/2015 10:17:58

I am working on putting together the second group purchase. Stay alert on the Network 54 FT Forum

kubi11

2/28/2015 09:08:02

amazon.com pyramidair.com

Alejandro O. Martinez

2/9/2015 13:10:46

Héctor, have you considered evaluating the Attacchi Ammortizzati Benaglio (http://www.benaglioattacchi.it/) recoil absorbing scope mounts. (http://www.benaglioattacchi.it/Attacco1pCaratteristiche.html)

References:

http://www.network54.com/Forum/184474/message/1393618918/last-1423529718/the+dynamic

http://www.network54.com/Forum/184474/message/1393628976/last-1423529718/CLOSE-UP-++BENAGLIO+ATTACCHI+AMMORTIZZATI+PER+TUBO+DA+30+MM

HECTOR J MEDINA G

2/10/2015 10:19:40

Not really. Completely different price ranges.

If $100 for a mount is hard to justify, double/treble that is much harder.

Sorry!

Alejandro O. Martinez

2/12/2015 12:45:21

The Attacchi Ammortizzati Benaglio mounts are going for approximately 109 Euros = 124.21 USD (http://www.store.armeriacaspani.it/aria_compressa/attacchi/benaglio_attacchi_ammortizzati_per_tubo_da_30_mm.html) to 115 Euros = 131.07 USD (http://www.armeriasportconsoli.it/attacchi.html). Not too unreasonably priced. I do realize international shipping and import tax(s) must also be calculated-in.

HECTOR J MEDINA G

2/14/2015 07:31:00

My Dear Alejandro;

If I were to bring those mounts in, there are costs you have not considered:
1) Customs inspection for export of ITAR related parts
2) Paperwork for export
3) Bank fees for money transfer on both ends of the Atlantic
4) US Customs brokerage fee and Customs themselves
5) Come commercial margin

So, what starts out as a €128 part, ends landed in the USA at something like €250 retail.

Compared with the first group buy offering, it is a substantial difference.

Alejandro O. Martinez

2/14/2015 13:18:18

Héctor, thanks for putting more into perspective the Attacchi Ammortizzati Benaglio mounts.

Marcos

4/15/2015 02:40:34

Hi Hector.

I need help trying to understand how this mount works. It seems to me a tricky dilemma.

I think we may assume the ‘number one priority’ of this mount is to protect scopes from rifle’s recoil. So, in order to not be confused, let’s forget for a while about the built in droop compensation.

To put it simple, spring piston rifles have two recoils. The first, kind of light and backward, when you pull the trigger (as a firearm). The second, forward and much harsher, when the piston suddenly reaches the end of its course.

As far as I know, it would be this rifle’s forward recoil the main cause for scopes’ damages.

So, in order to protect the scope from this forward recoil, the ZR mount should stay on the rifle with its white arrow pointing backward, to the shooter. Otherwise, the mount's spring would not absorb the forward rifle's recoil.

As for the built in droop (downward) compensation, it seems to me there is a “180 degrees” error. Anyway, if the scope's protection is accomplished, the droop issue (even enlarged) would be a secondary, and simpler problem to deal with.

Marcos

HECTOR J MEDINA GOMEZ

4/15/2015 03:19:44

Marcos;

Yes, there are TWO recoils in a spring-piston airgun as you state. And it is NOT ONLY the second, forward, extremely steep, recoil what kills scopes. Vibrations also play a role. Vibrations tend to loosen all threads that have not been locked. Once some looseness is in there, then parts have space to accelerate and when recoil comes, the accelerations/decelerations break the parts.

If you watch closely the frame by frame slideshow, it tells you what you want to know. I know it is small, but technology has its limits. Sorry.

In essence, what happens is that you are not "cushioning" the scope with a spring. What you are doing is allowing the scope to "free-float" in space.

Watch closely the distance between the base and the rail-mounted rings: From ms's 1 to 6, that distance is growing. Which means that the scope is STAYING PUT, while the action is recoiling to the rear. At ms 7, the action stops recoiling to the rear and commences its forward travel (very small). But still, the scope tries to stay put by simple inertia. It is not till ms 8 that the spring commences to drive the rail mounted rings to the original relative position to the base, which is now to the rear of where it started.

This means that when the piston reaches the forward end of the stroke and when the harshest decelerations take place, the scope is "suspended" in space and the very high number of g's do not have any point of contact to transmit a force that will break the scope.

THAT is how the ZR mounts do their job, by "isolating" the scope, NOT by "cushioning" it.

Since what you want is to isolate the scope from the forward recoil, then the mounting position is right with the arrow forward and the droop is correct.

You may be puzzled by the old externally adjustable target scopes that used a "recoil spring" (Lyman, Unertl, Litschert, Bausch & Lomb, Tasco), but you have to remember that those scopes were made for powder-burners that have ONLY the backwards recoil.

Hope this helps!

HM

Marcos

4/15/2015 15:34:13

Héctor.

Thank you for your patience and the quick and VERY didactic answer.

To be honest, I can't see what happens at each mS… Also, I think you should refer to a “normal” springer. In my opinion, the 54 introduces unnecessary ‘noises’ to think about, even more in a case already tricky enough by itself.

So, even in abstract, I'm trying to realize it about my 350 (Magnum recoil..), my ZR mount and my brand new scope, simple model/fragile, 4x32.

I have to confess that, after some weeks looking to this ZR mount spring.., right now, I’m still at the point – this is too good to be true.., but, at the same time, it’s overwhelmingly logic!

Congratulations for the excellent work!

Sincerely,

Marcos

HECTOR J MEDINA GOMEZ

4/16/2015 03:29:51

Marcos;

You are right, my friend. The 54 is indeed a complicated machine. Guess I am so used to it that I, unintentionally, tend to think of it as a "primary" gun while, in reality, it is not for everyone.

Thanks for your kind words. It is the writer's "food" to hear someone actually reads the stuff! LOL! Thank you.

In a "nornal" springer (without the sled system of the 54), the situation is still the same. Gun starts (ideally) from an "artillery hold", which is a loose hold, and will recoil first backwards, then forwards. Here, it may be worthwhile to note that while the backwards recoil takes place over 6 ms. the forward recoil stops the gun in about ½ ms. to change the direction of travel of the whole rifle in such a short time takes an enormous amount of "g's".

The sled system of the 54 is the "ideal artillery hold" by itself. Always consistent, always releasing exactly the same, always returning to the same point. BUT it applies to a reduced mass, as ONLY the barreled action is at play. When it is the shooter the one performing the artillery hold, then the mass of the stock, plus the arms and shoulders of the shooter ALSO form part of the system.

In the case of your 350, the whole thing will be there to absorb the deceleration of the sudden compression developed by the piston. And you need to add the mass of your hands, arms and shoulders. Depending on how tight or loose you hold the gun.

The last thing I want to say about the ZR Mounts is that you will never get scope creep or base creep. ¿Why? because there is no force applied now trying to make things slip.

Tighten things good and snug, but the 35 in-lbs of torque that are needed in some other mounts/rings are not needed here.
And that is also important for the scope.

;-)

Thanks again and Un abrazo!

HM

Tom

8/10/2015 14:13:39

Hector,

I just picked up a NIB set of these mounts. I've been told they have a reputation for not holding zero. Is there anything that can be done to fix this? A tool & die friend of mine owes me a favour, and he's good at his craft.

HECTOR J MEDINA GOMEZ

8/10/2015 15:38:42

Tom;

I have been using a set of "accurized" mounts for the last two months and a half, and I will be taking them to Europe for the World's that will be shot in Lithuania between August 14 and August 25th later this month.
Last Saturday I got twice the 3/8" @ 13 yards target that BCSA setup as a trainer:

http://www.network54.com/Forum/451309/message/1439075200/BCSA+August+8%2C+2015+Match+Report

So, yes, they can be MADE accurate.

The procedure is not complicated but, in life, the simple things are usually the best.
Cost would be around $60.00 + Sh.
If you are interested, send them to me (after August 25th) at the company's address:

Ct Custom Airguns
51 Hoyt St.
New Canaan, CT, 06840

BEFORE we tackle this, make sure that the scope you want to use WILL clear the watertable of the fixed section of the mounts.

MOST of the high power scopes that have an enlarged saddle will need additional milling to gain clearance.
Read the note on the Special Scope designed for US shooters, part I:

http://www.ctcustomairguns.com/hectors-airgun-blog/a-special-scope-designed-for-usa-shooters

to see how the mounts can be milled to accept scopes that have larger than normal saddles.

HTH

HM

Marcos

8/26/2015 05:32:56

Hi Hector.

I've decided to compare 3 mounts: a) one piece, no dampa, no brand..; b) DM 60; c) ZR mount.

Instead using a scope on the mounts, I've used a PVC pipe, about 8" long.

I've attached my mobile phone with an accelerometer app to the PVC pipe; the pipe was with some lead inside, and, also considering the phone weight, all together about the same weight as the scope.

It was a 3 axis referential. X (forward +/ backward -), Y (left/right) and Z (up/down).

I was not interested about Y and Z values.

Compared to the common e NO dampa mount, I was just interested about what 'fractions' would be the X values for the other two mounts.

I've shot 5 rounds with each mount; seated, front rested on a sandbag and with the 350 snugly on my shoulder.

For the negative X (backward), round average numbers: no dampa = -16, DM 60 = -15 and ZR = -16 m/S2. No relevant differences to me.

For the positive X (forward), average round numbers: no dampa = +10, DM 60 = +14 and ZR = +5 m/S2.

Please consider I was not interested about accurate measures, but just about the comparison..

Any thoughts?

Did you try something ""similar""?

Thank you, Marcos

HECTOR J MEDINA GOMEZ

8/28/2015 03:11:01

Hello Marcos!

VERY INTERESTING! THANKS!

No, I do not believe in the smartphones to that extent, LOL! I do use them as the platform for the PP Calc app, but the phenomena we are trying to see/measure here are so fast that I doubt the accelerometers in the phones can pick up the full scale of the acceleration/decelerations.

STILL, as a comparative analysis your data is extremely useful and to the point, congrats!

I find it interesting that the DM60 mount actually AMPLIFIES the forward section of the recoil, as it rates +14 vs. the + of the ordinary mount.

I find it even more interesting that the ZR mounts cut the forward recoil by 50% in relation to the ordinary mount and more than 2/3 in relation to the DM60 mount.

Thank you for some great data and I would say that you just proved my point. ZR mounts WORK for recoil reduction.
They do need to be accurized if you want to use for precision shooting, but for hunting, as a D350 is designed to do, they are ample accurate enough.

Keep well and shoot straight!

HM

Marcos

8/28/2015 04:53:58

Hi Hector.

Thank you for answering.

I decided to try just because is very easy to a common shooter to arrange it.

Btw, I forgot to mention the accelerometer has recorded the 'maximum' value for each axis; not the 'dynamics'.

I also don't know about the reliability at all.

Well, although the multiple possible imperfections within this "experiment", I was expecting the ZR would show a VERY different value in the negative X , about the - backward - acceleration (force) at the pipe (scope). In deed, I was expecting an "almost zero" value when the pipe was supposed to be floating..

As the big difference was in the positive X, I've kept thinking about the ZR spring. As a provocation to myself.. after all, would it be the only significant dampening factor in this "experiment"?

Marcos

Al Bergin

8/16/2022 00:05:52

Just purchased this for my new Diana54 mainly for the droop compensation factor. I noticed some slop in the mounted scope, lateral movement on the rails ? Is this normal? Didn't have much time to test it as with scope optically centered, ( Helix Elements 6x24 x50) pellets were hitting 6 " low at 21 yards. Took 120 clicks to bring it up to POA at 21 yds. Turrets horizontal adjustment maxed out at about 35 yards , AA 10.3 doomed. This was a good way to destroy the scope shooting it that far of center. Excessive barrel droop , sending it back under warranty to correct this. Was told this will be fixed in house, not sure what that means? Gun is brand new. They will probably just bend the barrel up but I hope not. , Maybe they will replace barrel and the receiver with a new component. I am not thrilled to have this done to a brand new rifle. I hope when I do get it back , these ZR mounts will function well . First Diana product , not impressed. .

Hector Medina

8/16/2022 10:42:24

Sorry you're having problems with the gun.
You can contact me directly through the contact page of this website and we can then continue this conversation over the EMail.

It sometimes happens that crates are not handled as carefully as we would like. A bent barrel is almost inevitable in a shipment of 300 guns in a container that also carries other merchandise.
Container ships are not the smoothest of sailings.

In any case, IME, I have only had to correct one D54 for misaligned barrel/rails and that was an extremely rare case.
In more than 350 cases (Accurized ZR Mounts sold and mounte to date), that is less than 1/3%
But, every gun is different and I understand your feelings.

Let me know which retailer you bought it from and how it goes.

HM

Al Bergin

8/16/2022 21:51:48

Thanks for the reply Hector.
Seems like my gun was the exception . Your explanations makes sense.
I purchased the gun at D& L Airguns, BC, Canada. I live in Nova Scotia, the other side of the Country. I did contact the them immediately with the issue hoping they might suggest I send it back
and they would ship another one. That didn't happen and was never suggested, very disappointing I now have to send it to a company called , Blueline Solutions They preform the warranty work for Diana guns here in Canada. They are also located in British Columbia . The gun will be shipped at my expense, all the way back across the Country again. I did contact them and received a quick reply. I would receive the shipping information in a couple of weeks.
As previously stated , pretty disappointing to have paid over $1000.00 for a new gun and now this. I will assume they are professional and have the expertise to correct this problem. It might take quite a while before the gun is back.
I'll let you know how it all works out.
I have a question about the placement of the ZR mount on the gun 11mm rail. I am unsure of which direction the mount is placed on the gun? I used the pin stop which placed the mount with arrow facing down the barrel towards the end? The open spring section of the mount is at the back so as to absorb the inertia created when the piston slams into the bottom of the piston chamber , correct?
Thanks,
Al

Hector Medina

8/17/2022 10:08:15

Al,
It's just an aspect of modern distribution.
Blue Line Global is the exclusive "importer of record" for all GSG (German Sport Guns) products.
Mayer and Grammelspacher (original owner of the DIANA brand), was purchased by GSG a few years ago.
Blue Line Solutions is the Canadian branch of Blue Line Global.
As such, and under normal distribution contracts, they are responsible for all warranty work and service.
I'm glad they have been responsive for you.
I know they have hired technicians and will surely do the right thing.

The ZRMounts do not "absorb" recoil in the traditional sense.
What they do is use the backwards recoil energy to "float" the scope while the rest of the shot cycle finishes.
After the shot cycle finishes, the spring returns the sliding part of the mount back to battery.
The cone at the front of that part "registers" into the hole on the fixed part and, for general purposes, register is accurate enough to hold a "plinking/hunting" zero.

For more serious target work, the mounts need some work.

The arrow in the mount should always point towards the muzzle.

HTH, keep us posted.

HM

Al Bergin

8/17/2022 23:44:34

Hi Hector,
Thanks for the explanation concerning Blue line Global and it's Canadian affiliate who will be working on my gun. Your comment stating they should have the expertise was reassuring..
From your explanation. Having the recoil destroy my scopes is not a good alternative but I don't think the ZR is the product I should have purchased for the D54. I am not a hunter nor a plinker . I am a pure bench shooter hunting for those magical dime size or smaller groups at 50 yards and a PCP is not for me, ever. What type of work needs to be done to the ZR to match the results of a good solid mount? It's probably out of my league of expertise what ever it is, darn! I really like the floating concept of the ZR. I have read all the reviews and it seems to be about 60/ 40. with the larger number being very positive comments. This is not just a slap in on and go mount. I think you really have to follow the mounting instructions but actual in/lbs torque numbers for mount and rings are not listed. Common sense suggests 12 ft/ lb rings, 30 ft/ lb mount screws.
If I can't get the ZR tuned up, and assuming the recoil doesn't break the scope with the traditional mount ,could you recommend another mounting system that might be more accurate?
I have seen your name come up many times why researching the Diana 54. You seem to be a Legend in your own right , not only for your shooting achievements but also your work and knowledge for the gun and products like the ZR mount. This is why I was so shocked and impressed when you actually took the time to respond to my issue.
I would like to find the best mounting system so as to achieve the most accuracy out of the gun .I have dropped Vortek kits into my other three springers , a TX200, R9 and 97K. They are equipped with the Hawke Airmax 30 WA SF 6-24 x50. and a Helix Elements 6-24 x50. and all incredably accurate. I think the Hawks are a fantastic scope , very clear glass. I would like to put one on the 54 if and when I can scrape up the money to purchase another one. But I need a good gun to put it on first so have to wait and hope it all works out.
This has been a somewhat stressful time for me but for you to share your time and invaluable knowledge has really helped,
Thanks again Hector.
Al from Nova Scotia.

Hector Medina

8/29/2022 13:10:39

Hello Al;

Sorry for the delay. At last I am back.

In reality I have found no other alternative to an Accurized ZR mount.

The Dampa mounts do not repeat the return to battery, and the fixed mounts do not isolate the scope from the vibrations.

I have seen scopes mounted on ORings, floating magnetic mounts, and even a spring loaded mount that seems to work by Gamo. BUT, the reality is that after a few years, the ZR Mount is still the only one that is still being sold in good numbers, which should indicated that for 90% of the shooters, it does a good enough job.

For FT shooters, and others that pursue extreme accuracy, I ahve prepared more than 140 ZR Mounts, and they have all had good success with them.

When you get your gun back, please contact me through the contact page of this website, and we can decide together what to do.

Keep well and shoot straight!

HM

Hector Medina

2012 US National WFTF Spring Piston Champion
2012 WFTF Spring Piston Grand Prix Winner
2013 World's WFTF Spring Piston 7th place
2014 Texas State WFTF Piston Champion
2014 World's WFTF Spring Piston 5th place.
2015 Maine State Champion WFTF Piston
2015 Massachusetts State Champion WFTF Piston
2015 New York State Champion WFTF Piston
2015 US National WFTF Piston 2nd Place
2016 Canadian WFTF Piston Champion
2016 Pyramyd Air Cup WFTF Piston 1st Place
2017 US Nationals Open Piston 3rd Place
2018 WFTC's Member of Team USA Champion Springers
2018 WFTC's 4th place Veteran Springer
2020 Puerto Rico GP Piston First Place
2020 NC State Championships 1st Place Piston
2022 Maryland State Champion WFTF
2022 WFTC's Italy Member of TEAM USA 2nd place Springers
2022 WFTC's Italy
2nd Place Veteran Springers
2023 WFTC's South Africa Member TEAM USA 1st place Springers
2023 WFTC's South Africa
2nd Place Veteran Springers

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A high speed analysis of the way the ZR Mounts work

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