How to Avoid a Common Mistake When Mounting Your Rifle Scope

[@jamespollard1670]

We can all agree , if the screws are loose , it will move .

[@bobhamulak3646]

Yeah, it seems like a no-brainer to me! I don't want my scopes moving forward OR backward, so I make sure all screws are sufficiently tight! PERIOD!

[@jppiercy9154]

Wait......how can we be sure?......lol😅😅😅....like how 'the words book says???........Naaaahhhh!!!!....😅😅😅...

[@danakinscheuer]

I installed this optic on a crossman 760 air rifle.I have now shot the riffle around 500 times during target/plinking practice, and the kzbin.infoUgkxc4K63Fd5LglDMObu7-Bgapxp_ef0W8hE scope has done well.With this optic, I have neutralized around 30 pigeons that were invading one of my buildings.For my short range air rifle, I will continue to use this scope, but will be upgrading to a more powerful scope, when I buy a more powerful air rifle, in order to shoot at longer distance.For the money I have spent, this scope has truly been a great buy.

[@bretboyd7114]

I have been mounting scopes as a gunsmith for over 40 years I have always pushed the front ring forward back ring to back tighten to 15 inch pounds on ring caps and 25 inch pounds on base screws. My rifles have been all over the world by vehicle and plane never had a scope move

[@brandongriffin1990]

This makes more sense than anything right here!

[@languagesource355]

Come to think of it, this covers all bases, pun intended! The sad part is: people who are not scientifically inclined will conclude from this that the experiment proved the engineer wrong, without critically trying to understand what's happening. Newton's laws are not wrong. There's just more than one vector during recoil - first back (initial recoil), then forward (after the shoulder resistance), so the scope mount experiences these in turn. And it will move where there's available travel. So setting the base forward against the rail will prevent movement forward, but allow the movement backward, if available. And setting the base backwards will keep it from moving that way, but not the other way, if travel is available. Personally, I had a couple of scopes gradually slide forward in the rings (not on the rail) under 45-70 recoil, all the way to the turrets/ocular. This was the rings' fault, I think.

[@languagesource355]

Makes me wonder about single-piece cantilever "sled" mounts, how would you mount them?

[@tonyyoung4223]

If the screws are loose enough the scope will move backwards after moving forward and bouncing off the forward picatinny lugs. Under recoil of the rifle the barreled action has a rearward G force that the scope/mounts have to catch up to. The most force of recoil is when the bullet leave the barrel and the scope is pulled forward from recoil force of the barreled action moving rearward while the scope is static. The moving backwards is a secondary action caused by the scope mounts bouncing off the picatinny lugs in front of the ring lugs.

[@customgunsammorepairs]

Tony, That’s not what the video seems to show. Video shows the scope marches back. Perhaps you could argue that the scope bounced off the front rail on the first shot. I don’t believe it did, but if you make that argument, once the scope is off the front rail, how does it continue to march back on the following shots? Tim

[@gouldgibbonsiii4742]

Exactly. Tony, I agree 100%.

[@scottluther6699]

@@customgunsammorepairs actually it didn’t look like it marched back anymore after the first shot. I replayed the video and it doesn’t appear to move backward after first shot. If you’re convinced your right, redo the test again starting at the back. If you are truly correct, it shouldn’t move at all.

[@customgunsammorepairs]

@@scottluther6699 Scott, The scope mounts started on the front rail of the base and stopped resting on the back rail. If you are correct that all the movement occurred on the first shot and the scope mounts did not move further on the last three shots when up against the back rail, then the test you suggest we do has already been done. Tim

[@phillipcaster8605]

Tony your 100% correct! I have my grandfather’s old Sako L579. The scope rings mount to Sako’s proprietary tapered dovetail base machined into the receiver. There is no picatinny rail for the rings to bounce backwards from. Instead what happens is the first few shots will drive the scope rings forwards into the taper creating a tighter scope ring to receiver fit. Removing these scope rings requires a wooden dowel and hammer to tap them back off the receiver. If the “video interpretation” was correct, my scope would fly off the rifle after a couple of shots. So if anyone wants a definitive professional opinion call Sako engineers and I’m sure they’ll clear this nonsensical video presentation right up. And yes the Sako rings I am using has a side clamp that I torque to 65” lbs, after I have fired 3-4 shots to fully seat the rings.

[@GUN-TV]

I am an engineer and the mathematical engineer and forces says the scope will move backwards. You now why? After shooting the recoil will move the stock backward, after that that the shoulder of shooter will stop the recoil and mange the stock going forward, so as the second role of Newton says the hole system of scope will moving backwards due to the shoulder forward movement of stock. Yeah thats the point gus 😅. So Mr. Tim Muss says right and the PhD guy said false. By all thing into consideration, the scope have 2 step movement. Step 1: Rightafter of shooting the scope will move forward. Step2: After blocking the recoil of the weapon, the shoulder will apply force to the butt and cause it to move forward. At this moment, the whole scope system moves back. Here, we find out that, the firmly mounting scope in place is more important than tightening the scope to the back or front of the picatinny rail. But my personal opinion is to fasten the scope to the back of the Picatinny rail as Mr. Muss said. Thanks for reading the comment 😂❤❤

[@customgunsammorepairs]

Exactly right. Makes me wonder if the manufacturers prefer scopes being mounted forward because it could be easier on the scope during recoil? Less stress on the scope would mean less warranty work, which hurts profits.

[@iallreadyknowsunshine57]

Moral to this story is-make sure all your scope mount screws/bolts are tightened to the correct torque specs and neither forward or rearward movements will occur.

[@MrNeverlost1]

I'm not convinced because you only performed 1/2 of the demonstration. I would like to see you mount the scope to the rear, and use identical torque to see if the scope moves forward when fired.

[@drewb5738]

You have to do the test again with the scope mounted forward. It’s hard to make a claim when you only tested it one way. My guess is that a loose scope will move in both directions, which, if true, means that these tests do not provide any evidence to support your theory.

[@customgunsammorepairs]

Drew, We have two videos. One with the scope mounted to the front which the scope moved back. One with the scope mounted to the back and scope does not move forward.

[@alantewebdesign]

@@customgunsammorepairsDoesnt count if one was loose ans one was tight lol.

[@bwr3rd]

In a similar fashion, when mounting a barreled action into a stock, you should hold the stock and barreled action in a vertical position (butt down) so that the recoil lug rests against the inlet on the action side. This prevents the barreled action from moving rearward when fired and thus improves performance.

[@customgunsammorepairs]

Absolutely correct. Good tip.

[@jt8180]

You are absolutely correct! That is why when I use a picatinny rail, I always use rings with a locking lug in the base. That way it is impossible for the scope rings to creep backwards..... Nicely Done.....

[@michaeldoe4805]

Only the mechanical forward stop is strong enough to withstand the initial recoil and the tendency of the scope to shift forwards. The mounting screws and friction will take care of the rearward movement of the scope when rifle hits your shoulder and comes to a gradual stop eventually. Long story short, during a firing sequence, scope wants to stay still (as all objects do) so the first force is rifle coming back and hitting the scope VIOLENTLY at the front of the scope, then scope and rifle starts moving backwards towards your shoulder and rifle comes to a stop GENTLY, and scope wants to still travel backwards but now being held in position by mounting frictional forces. So, the more violent slamming of the rifle and the scope happens at the front of the scope, that's why we always mount scopes physically resting forwards with mechanical connection. Otherwise, the screws and mounting friction cannot withstand that violent slamming. But, they can withstand the forces generated because of the rifle coming to a gentle stop on your shoulder

[@customgunsammorepairs]

Makes sense, but I’ve not experienced rear mounted scopes marching forward, only forward mounted scopes marching backwards.

[@dvet9]

"No, I understand impulses. I'm having one now!" Priceless!!

[@danfabisac]

The first man in the world to kick physics ass.

[@danellebarnette6380]

Even though engineers are very smart they are usually bullheaded. Assuming nobody outside of a engineer isn't smart enough. I run into this a lot in my profession as a tech!

[@customgunsammorepairs]

Best engineers I’ve met gather information from techs and other reliable sources before jumping to conclusion. I once told my doctor that coming to conclusions without investigation is self induced stupidity. Doctor dropped me as a patient claiming I called him stupid. I guess he, like many people, jump to conclusions without investigating.

[@danellebarnette6380]

@@customgunsammorepairs "Self Induced Stupidity" couldn't have said it better myself!

[@clarence4735]

If its mounted on a picatinney its only going to move a tiny bit either way and not have any diffrence on target. Onece it seats either way give it a snug and be done

[@joelsmith6050]

I disagree. I've experienced scope creep forward several times, never backwards. I commend you for discussing the issue, but I think you have a faulty test.

[@dragonflyfab9703]

Objects at rest tend to stay at rest. Objects in motion tend to stay in motion.

[@savage22bolt32]

The scope on my springer air rifle moved back, then it fell apart. Now I use the iron sights.

[@jeffmurphy9987]

I personally follow the manufacturer recommendations. All of the scopes I’ve had never moved rearward. Just my experience.

[@customgunsammorepairs]

We frequently get firearms in with complaints of accuracy issues. One of the first things we do is check the screws on the rings and bases. Frequently tightening them to spec solves the accuracy problem. Rather than having a torque driver, many shooters guess as to whether screws are tight enough. We’ve found the other frequent cause of loose scope or base screws is air travel. Airlines can be rough in handling baggage and airplane vibrations can loosen screws. The experiment we did on video was to see which direction a scope moves with screws not torqued to spec.

[@mikefinley4367]

Amazing that a college educated engineer, doesn't comprehend expansion and contraction which by the way is the biggest used pattern repeatedly in creation.

[@garywalsh7322]

Lets take a look at a scope from a while back. Unertl, used an external spring with compression against the front mount and secured with a tension adjustment ring to return the scope back forward after firing.

[@aaronsmith21]

This is the exact opposite of what I have heard and have been doing. You should move the mount forward as much as possible before tightening.

[@codyjudd6164]

Another way you could have explained it is how an axehead is seated onto a new handle. The furniture moves backwards when the rest of the element runs forward.

[@waynevandetta2455]

It will march backwards if your shoulder is stopping the recoil. Under free recoil it will march forward. Thanks

[@customgunsammorepairs]

Wayne, Tried it under free recoil and still moves back. Tim

[@willelliott5052]

I can't explain why the scope moved backwards, but there must be a reason why some rails come with a protruding tab that is to be shoved against the front of the ejection port.

[@JohnHilman1968]

What I do is mount the rear ring so that it is against the rear of the rail lug. And the front ring to the front of the rail lug. Torqued down to correct specs and vibratight on the screws to lock them in place. Ring caps torqued down to correct specs. And this is on my Browning X-bolt .300 wsm with no brake. It has not moved in years. ;)

[@yuccaman3545]

Thinking about it's possible that during the initial recoil the scope is moving forward, but as the rifle comes to a stops from the impact into the shoulder the scope comes to a rest rearward since that is the last force exerted on the scope. Maybe a high speed camera would be able to pickup the movement. Either way proper torque, blue loctite and carrying a torque wrench in your travel kit to validate torque setting prior to a hunt/shooting session is key. Missing a big o' buck for a $50 tool?

[@DeeDee-vu5mi]

I agree. Its only gonna march back so far, which IMO is the tolerence btween the rail slot and the shaft that goes across the slot.

[@Mantitude]

Meanwhile, I just press the front ring against the rear surface of a picatinny lug, and the rear against the front face of another lug, and then properly torque the screws/bolts. Has worked thus far.

[@russellehrgood9835]

Makes sense, if the firearm recoils backwards, the scope will too. I have seen some videos by manufactures to mount the optic forwward.

[@jppiercy9154]

I always loved engineers......I read a book.....lol.....meanwhile us mechanics, living in the shit, day to day proof otherwise......like they can't comprehend.........bwaaaah.....😂😂😂...

[@jppiercy9154]

Easy money......

[@dougcook9282]

You are right. But an exception is a piston air rifle.

[@jackvaniciaadams4089]

I've found the rear scope ring to mount to the rear against the rear rail and the front ring to the front of the rail. I've found that all but one in my life march back. So.. an ole timer showed me this way. It can't go forward or backward. Never had another issue. I agree with you but I did have one go forward for some reason over 50 years. That saying I can say this is about 4 or 5 rifles out of about 50 or so rifles. Loose screws mainly. One set of faulty rings.

[@vwmountainman9701]

Not to start an argument - Just a comment - I have a Sharp's 45-70 w/ Montana Vintage Scope.. The scopes are meant to float - so the recoil does NOT knock the reticale loose inside. These scopes slide forward. As they are meant to move. So - before each shot - the shooter must remember to slide the scope to the reward position. Might be scope design - I'm not a PHD in anything. I did see that ur setup shows the scope moving reward.

[@tdmmcl1532]

I confirmed this same experiment with a "magnum" air rifle...picatinny rails. What I did was place painters blue tape at a KNOWN distance..precisely 1 mm just behind the rear scope ring on both the scope AND the barrel. (remember, there are two different assemblies here mechanically joined by tension/compression). I also place painter blue tape at a KNOWN distance, precisely 1mm just FORWARD the front scope ring and also at the scope. A "magnum" air rifle is: accelerates the pellet to supersonic speeds. Classic "crack" at muzzle is heard....typically about 1130 fps. . These higher powered air rifles even when "down rated" with heavier pellets still develop tremendous forces throughout the entire barrel breech scope mount assembly. Even when properly torqued and blue locktite, after about 100 shots, there is a noticeable creep of the scope AT MOUNT/rail AND ALSO the scope itself within the rings. The creep is more noticeable at the mount/rail attachment than the ring/scope attachment. So I then decided to start thinking about the physics involved in simple terms. It's mass and acceleration = force.. If one can reduce the WEIGHT of scope and rings and mount to rail, one can expect the FORCE to be reduced. Also thinking about physics in terms of center of moment...the longer the center of mass stands AWAY from the center of mass OF THE ENTIRE RIFLE...the higher the forces will be ...think of it as a simple LEVER. Thus, we want a scope and mount that is as close as possible to the rifle center of moment. when you put these two simple things together you have: use the lightest weight scope, rings and rail system you can install it as close as possible to the rifle. as far as preventing scope "creep" from these forces, Frankly, I do not have a good practical recommendation other than following some basic torque and thread locker advice. So have offered the idea to use BOTH forward and rear scope mount stop as two dead anchor bookends. Others have offered that instead of two separate scope rings go with a single block style where the torgue surfaces are spread out over a longer distance of the barrel. I think all of these things are worth exploring. but in my experiment this is what I found. yes, creep happens...but at a certain point, its just stops moving. It's either going to continue to creep OR it "jams" to one fixed place, shot after shot. This "jamming" effect is exactly what I found with my scoper air rifles...To INDUCE IT, I USED SMALLER WEIGHT PELLETS ON PURPOSE TO PRODUCE THE HIGHEST FORCES POSSIBLE. And after the creep stopped..about 300-500 pellets, I moved up to what the air rifles really shoots accurately (subsonic), at the higher weight pellets. I believe these shadetree "experiment" do cross over to powder rifles as the same principals remains the same. you are welcome

[@sidewalkhillbilly6636]

How about mount the front ring pushed forward and back ring push backwards or vis versa, then torque the rings down extra good. Then Your covered both ways

[@joeyzagari4155]

Interesting. I would intuitively think the rifle recoils backward and the stationary pic rail and/scope mounts creep forward, like pulling the table cloth from under the glass. The stationary scope inside the stationary rings would also creep forward. However I can also imagine a bouncing wave like a spring could also be happening, the scope in the rings is flung forward like a driver in a car crash and under momentary tension at its maximum is then flung back as if the rings were like a seat belt and the energy stored under tension has to spring back and release drives the scope and rings backwards during a reflecting wave carrying momentum. Sounds like a job for Steve Mould or Smarter everyday channel to answer with the help of super slow mo camera guys.

[@aaronsmith7854]

I'm sorry your wrong. The scope moved back because it couldn't go forward and once the recoil impulse was transfered to your body it moved back because it couldn't go forward. Do the test in reverse and I bet it goes forward. I had a set of rings with no recoil shoulder just a dove tail and the scope almost came of the front of the rifle.

[@josephrogers8213]

Engineering states a bumblebee can't fly

[@oubliette862]

I like the left hand bolt on that gun, very nice. I only have 1 rifle with a scope and as far as I can tell its never moved.

[@franzfranz9144]

With loctite and proper torque scopes should stay put right?😇

[@Lisabarrington]

Yes!

[@franzfranz9144]

@@Lisabarrington Have not experienced optic creep due to recoil. Installed correctly they do not move unless abused.

[@Lisabarrington]

Exactly.

[@kalliste23]

Theory guides but experiment decides.

[@allexthebeast93]

When the scope rings are separate, then one is torqing towards the front and other towards the back of the play in picatiny chanel where it seats! But, when you torque it up to 55 in/lb you'll have no issues whatsoever!

[@bobcole9274]

I know that it moves backwards, I just wish you had a slow mow close up. Before I got a Torque driver I was cautious and did not tighten enough.

[@REDNECKROOTS]

I e had this same argument so many times. You are correct sir !

[@sappysiggy2351]

I just mtd one last night and considered the slop in the Pic rail for the first time and mtd it Forward, Redo tonight. Whiplash type effect?

[@lxrrxl]

Can you repeat experiment with the same torqued screws but mount it to the back to see if it moves forward?

[@xenomorph1317]

You also have scope ring caps with three screws, so what torque do u use then?

[@srankin8022]

This is odd to see. I have a 44mag Contender pistol and could never get the rings tight enough to keep the scope from moving and eventually just let the turret housing come to rest against the front ring. not what I wanted but it was the only solution I could get to work. So, it seems odd that the mounts move rearward on a picatinny rail, but the scope moves forward in the rings.

[@customgunsammorepairs]

Have you considered that possibly the dynamic forces exerted on a rifle are not the same as those on a pistol? Rifle is stopped with your shoulder, is heavier and usually has less recoil. A pistol has more recoil due to light weight and your hand offer less resistance than a shoulder.

[@srankin8022]

Well, I hadn't given it any thought until I watched your video. I've never had a scope move, to my knowledge, except on the 44 magnum. Yes, the 44 magnum with stout loads for the contender has quite a violent recoil rearward, and the hand slowly stops the recoil. Whereas I suppose the rifle has a slower recoil due to the weight and slower burning powders and then a more abrupt stop, your shoulder. Have you ever thought about the possibility that the scope on that rifle you were testing might actually move forward a bit when it fires and then be slammed rearward when hitting the shoulder? After all, the scope is at rest when the rifle tries to leave it, just as in the case with the pistol. I've never had a scope move except on that contender. This is a great video and one that definitely made me re-think the situation.

[@glennanderson2790]

So this is a very interesting video. I’ve had two guns in my lifetime that have moved in the rings. The first was a 12 gauge shotgun where the scope slid back as you demonstrated, the second was a muzzleloader just last year that did the opposite and slid forward.

[@customgunsammorepairs]

Glenn, I believe when screws are slightly loose the scope has a tendency to move backward under recoil, but when the screws are very loose the scope has a tendency to move forward, or actually stay in place as the gun moves backwards under it, sometimes in dramatic fashion. Most people notice a scope moving forward with extremely loose screws and I think that’s why most people are under the impression that if a scope is going to move under recoil, it moves forward. Most people don’t notice the movement of a scope creeping backwards due to screws that appear tight, but actually aren’t torqued to factory specifications. Tim

[@glennanderson2790]

@@customgunsammorepairs That makes sense to me. On the shotgun the screws for the rings were snug and on the muzzleloader they were very loose.

[@kennethunkefer7163]

So... If what you are saying is true. Why does an Unertl scope need to be pulled rearwards to reset for the next shot? One that is not equipped with a spring anyway. Some are, some are not. The scope slides forward during recoil.

[@customgunsammorepairs]

In my opinion there is a forward motion imposed on a scope upon initially firing the gun, but the secondary rearward motion is stronger. As for the Unertl scope, I don’t have hands on experience with them, but I can tell you what I’ve heard and read. The Unertl scope had very short eye relief and the internals were not very rugged. The allowed movement and spring was to keep the scope being damaged. The spring acted as a shock absorber and the movement prevented the scope, since eye relief was short, from hitting the shooter’s face. Upon Colonel Townsend Whelen’s observations about the scope, spring was removed for military use and upon firing the scope would reset itself if the rifle had some modifications allowing it to do so. The earlier scopes with springs mounted to heavy recoil rifles had a tendency to compress the spring upon initial firing and then hit the shooters face upon the rearward motion of the scope. As mentioned before, that’s not from hands on experience, but from accounts of others. I tend to think that information would seem to align with my observations of scopes marching

[@ericrumpel3105]

.....witness marks don't lie, same as a scope that slides in rings from recoil - it moves rearward,.....just happened to my buddy a year ago,....must be from the recoil being arrested so quickly on the shoulder while in full vibration & harmonics.

[@YouveBeenMiddled]

It's obviously due to the wrong-handed rifle.

[@glenlivett78]

The video shows what it shows, kind of hard to argue, but it sure goes against the common logic. They didn't steal me from MIT so I don't know what the PHD was trying to say but I do know the old Unertl scopes the military used had the rear of the tube free floating to allow them to move when it accelerated under recoil and the shooter and had to pull the rear objective BACK after each shot because it drifted forward under the recoil.

[@glenlivett78]

clearly, there is a gremlin in the formula the good professor was trying to convince you with

[@cbsbass4142]

Demonstrating Scope moved forward here then resets backward, hence the spring kzbin.info/www/bejne/Y5fUk6idi9d4ps0

[@kilekinney253]

the brake make a lot of difference in recoil and scope movement mount in middle and remeasure

[@heathhalfhill6401]

Marches forward! ha ha ha maybe on a strong break barrel airgun. Most of my mounts have a bolt that goes across the pic rail grove that stops any rearward or forward movement like experiences on some airguns that have reverse recoil. Using a torque wrench is the best way to prevent any movement as you said.

[@teddybaham6673]

When I mount One it don’t march anywhere, it stays put

[@johnsmith-ub7vr]

Shooting starts at 5:30

[@davidshatusky8755]

I believe the scope moves forward. The recoil of the gun is pushing it back so fast that the scope or any mounted device will move forward due to the gun moving so fast under it. Put anything on a board and simulate recoil and see which way it moves. The gun moves back, and mounted devices move forward. Fact.

[@customgunsammorepairs]

Putting something on a board and simulating recoil is not an apples to apples comparison. The rifle has a scope base, rings, then the scope, which are fixed in place. Will give a different reaction than placing something on a board.

[@jackson4861]

A more important question when referring to supposed Precision equipment, why is there enough space for it to move at all?

[@customgunsammorepairs]

Jack son, That’s how Picatinny rails are made. Tim

[@jackson4861]

@@customgunsammorepairs yeah, my point exactly it’s not precise enough, bad design.

[@stevo1166]

​I agree with your point, no slack, no movement, no arguments. The slots on the rail and the bar in the ring mounts should be precisely engineered to a snug fit. ​@@jackson4861

[@yuccaman3545]

Very interesting and thanks. Would be great if someone with a accelerometer could measure the forces on the scope on the initial recoil and when the recoil stops. Formula/equations are great and does solve a lot of things but until it is validate by real world experiments its just theory. Nice work.

[@stephenheer8449]

you both are correct - with the firing of the rifle the scope moves forward and stays forward until the but of the rifle enconters a sholder or stop but if and when it does the scope will shift bacwards more than it did forwards because the rifle is heavier than the scope. The scope moves forwards perportionaly in relation to the mass of the scope where as it will move backwards perportionally in realtion to the mass of the rifle

[@customgunsammorepairs]

Stephen, I believe deceleration exerts more force than acceleration. That’s where the backward movement comes from. Say a scope shifts forward 1/32” right before it shifts backward 1/8”, most people would still conclude the scope marches backwards. Tim

[@stephenheer8449]

​@@customgunsammorepairs thanks for response - yes the scope takes one step forwards and two steps backwards but in this situation would it be wrong to wonder as to why? that the greater two steps backwards might not be resulting from the rifle being heavier (greater mass) and being stoped "deceleration" compaired to that of the lighter scope (less mass) and initial "acceration" of rifle towards the stop

[@customgunsammorepairs]

@@stephenheer8449 Stephen, I think it’s a good thing to question why. I also think, upon rapid deceleration, a lighter scope would exert less force than a heavier one, which means a heavier scope would be more prone to move back. I also think the heavier gun in same caliber would be less prone to make a scope move. In the same caliber the heavier gun has less recoil. Tim

[@williamgaines9784]

@@customgunsammorepairs the sum of the forces is zero. The mount forward "rule" is because the scope moves 2nd. The scope will suffer less shock if its ring base is mounted forward in the weaver/picatinny cutout, because the rifle will not move as far ahead(behind) of the scope ring base before the base begins to move. If it is moving rearward, that is occurring on the rebound where the gun is moving forward from your shoulder while the scope is still moving reward. Having rings that fit the base and the scope properly, then tightening sufficiently, reduces the movement. Think of which way you fall when the rug gets jerked out from under you. It is the opposite direction the rug is pulled. Same or the scope.

[@customgunsammorepairs]

@@williamgaines9784 William, I believe the bullet puller or car accident analogies are more applicable in this case than the pulled rug analogy. No trick photography was used. Why did the scope not march forward? Tim

[@michaelbarrett2346]

Thank you

[@Bigfish1day]

Get precision scope rings, the recoil lug fills the pic slot, no space to get play

[@7norton4]

Would be interesting to try the same experiment using rings with lugs removed.

[@jerrycandelaria8845]

I believe the engineer is probably a student of the same engineer that said a helicopter can fly

[@flightbyrd]

PhD left out a negative sign in his calcs.

[@MoSportsUSA]

Simply put, under recoil the gun is accelerating backwards while the scope is momentarily stationary. Until it catches up to the rearward recoil of the gun, it wants to move forward. Mount the scope on the rail and push it that slight bit forward in the Picatinny slots before tightening.

[@albertramirez1501]

I have always known that it moves backward. But should we be saying that it settles back after a shot

[@nevisstkitts8264]

The rail standard(s) has/have no specifications for maintaining zero. The requirement to maintain zero falls on the mount and optic side. The manufacturer sets the quality on return to zero and maintaining zero with their proprietary methods which include instructions on how the mount and optic are installed, positioned, and fixed in the rail ...

[@jofo1736]

SEND THIS TO THE "slow motion guys" to watch in slo-mo. Maybe it'll show it bounces front to rear and or back to front !!

[@c.showers6859]

It looks like this is a result of different coefficients of friction between the scope rings mounted on the picatinny rail and the scope itself. If it were possible to slow the footage down, we should see the picatinny rail is sliding from underneath the scope mounts as the rifle accelerates "backwards" due to recoil, suddenly decelerates to "zero" as it hits the shooter's shoulder, and then reaccelerates "forward" as the rifle itself (picatinny rail) has changed directions. Since the scope is fixed to the mounts, it moves at a different pace than the rifle (fixed picatinny rail) and we begin to see what appears to be the scope creeping backwards. A different way to explain it that what we're seeing is two objects moving at different paces due to the result of one of the objects being impacted by reduced friction. If you completely fix the mounts to the picatinny rail, the mounts do not move, the scope says stationary, all because the impact of the recoil and the resulting coefficient of friction is the same for all...the scope mounts, picatinny rails, and rifle. That's my thought!!!

[@minhquinn439]

So what are the proper torque specs generally?

[@customgunsammorepairs]

Minh, Varies by manufacturer, but in general scope rings to Picatinny rail around 15-25 in/lbs Tightening rings to scope tube around 15-25 in/lbs. Tightening Picatinny base to action around 15-55 in/lbs. Tim

[@minhquinn439]

@@customgunsammorepairsThank you. Yea after I asked the question I looked it up on IV8888 channel and they said the same thing. They used red lock tight though. And some guys in their comments said maybe blue lock tight, but not red, and some said don't use lock tight at all. What are your thoughts on applying lock tight?

[@Wheelchair-bear]

Thank you, I had always mounted it forward, the bullet remover was a great example. I will always mount them back from now on.

[@mikegreen2214]

Then you’ll be doing it wrong.

[@jdr285]

Look at how the UNERTL scopes work. Real world answer.

[@joe-dp3ng]

It's exactly like when you take an axe head and hit it on the bottom on the ground to make that axe head seat backwards yeah there you go okay

[@stevewalker4638]

I always put Loctite on the screws check your your gun after a long trip that it’s on target..

[@miker2888]

Repeat this experiment with a .22 and 3/8” dovetail . There shouldn’t be anything for it to bounce off of. I remember when I was younger shooting a .22 a lot, the scope did walk backwards

[@michaelthrelkeld212]

Hell any scope will move if the mount is not torqued properly

[@abengelbrecht]

The scope slides backwards since the bolt is lefthand 😂 For a proper scientific test you need to test both conditions of forward and backward using the same method i.e. looser then spec mounting bolts with the scope forward and backward. To refine the test increase the bolt torque slightly and actually measure how much it moves in each situation.

[@bobgyetvai9444]

I mount 1 forward and 1 rearward . No slop , no movement .

[@calvinmulford6110]

All you proved is that you need to torque it down properly . Both times scope has moved on you screws were lose on your rifle so it has nothing to do with mounting forward or back

[@dannyblackburn1972]

Also depends on the caliber… !!!

[@josephrogers8213]

Before and after shooting or traveling scope and rifle should be man handled. Scope to action . Action to stock. And back again You may not see it. But sometimes you will. feel it . Especially if groups are opening up

[@garyendres2266]

They move backward it is a fact and I have had one do it also 👍🏻

[@paulbishop5569]

Spring airguns are opposite of firearms in recoil. Every free-recoiling external adjustment scope moves forward. That is why the stop is forward of the front ring. You must pull the scope rearward to the stop after every shot. Of this I am certain. Anything can happen in an experiment where screws are left loose and recoil stops are in place. Incomplete test!

[@customgunsammorepairs]

Paul, This has nothing to do with air guns or semi autos. The video addresses bolt action and break action center fire rifles. We tested with tight screws and loose screws. In both instances the rings crept backwards. You are correct on air guns. Totally different dynamics involved with air guns. I broke many rifle scopes as a kid putting them on air guns.

[@jaredmaki892]

Ok- so now do the same test, with inappropriate torque in screws mounted rearward- let’s see what happens…

[@davidmartin4774]

With the rings you are using and loose it will move forward or backwards due to the no lug in the picatinny rail slot .you just proved you are not going to keep a high recoil rifle with loose rings in zero

[@cw5865]

Great demo and the use of the bullet puller will produce the opposite from the internal force going the opposite direction. That said, the body stopping the recoil is like the puller... However the pulse of the powder is far more severe as your "non-PHD" education appears correct as the body is stopping the recoil and thus a rife in motion remains in motion (used to be elementary school education stuff) until it meets another force. I started watching this recording thinking you will be wrong (sorry college educated in aeronautics no less) to realize we hopefully don't meet the opposite force, the ground in this case... Yeah your are right. using common sense and Newton's Laws, damn. I want my money back...

[@saucethekat]

snottie aeruonautics

[@Riley_1955]

I always mount my rings in the grooves so they are tight against the rearward of the rail groove and to see if the scope moves in the rings I have always used a minuscule lead pencil mark on the rear of the top of the scope right where it meets the top scope ring to see if it moves in the rings.....So if your scope moves the mark will also move back away from the ring.

[@languagesource355]

The sad part is: people who are not scientifically inclined will conclude from this that the experiment proved the engineer wrong, without critically trying to understand what's happening. Newton's laws are not wrong. There's just more than one vector during recoil - first back (initial recoil), then forward (after the shoulder resistance), so the scope mount experiences these in turn. And it will move where there's available travel. So setting the base forward against the rail will prevent movement forward, but allow the movement backward, if available. And setting the base backwards will keep it from moving that way, but not the other way, if travel is available. Personally, I had a couple of scopes gradually slide forward in the rings (not on the rail) under 45-70 recoil, all the way to the turrets/ocular. This was the rings' fault, I think. The gunsmith below who mounts front ring forward and read ring back has cut to the crux of the matter.

[@customgunsammorepairs]

If you read all the comments from this video and the follow up video you’ll see that many engineers agree with mounting the scope rings towards the rear of the picatinny slot. From my experience engineers are very scientifically inclined, so you really have nothing to be sad about.

[@languagesource355]

@@customgunsammorepairs a consensus of many (or more specifically "some") is not how things are established. When you understand physics, you don't care how many engineers say anything. There are several comments that explain the duality of force directions acting on the scope. And even a comment specifically stating that the video only had half of the experiment. And a few experienced people saying they set the front ring forward and rear ring backward. Respectfully.

[@customgunsammorepairs]

I must not have understood your first post because it looked like you were giving weight to an engineer’s view point. In response I pointed out other engineer’s view points, since you seem to give more credence to the scientifically inclined, but their opinion doesn’t matter because it’s opposed to yours. Interesting how that works.

[@languagesource355]

@@customgunsammorepairs I think you have yet to understand what I really meant. I meant that people will take the empirical demonstration as "proof" in lieu of understanding what's really happening. Empirically the Sun revolves around the Earth. And someone else can do a video demonstrating the opposite setup and also empirically "prove" something. Still without painting the complete picture.

[@customgunsammorepairs]

Very amusing that I must not understand if I don’t agree with you. Well then there are a lot of people, including engineers that don’t understand.

[@theheck5176]

It does move back.

[@geraldgrieve4106]

Problem...left hand rifle fired by a right hand shooter.

[@kristijanmedved6066]

Put one ring on front and the other on the back so there is no chance it will move..

[@blastradiu5]

TL;DR buy a torque wrench and tighten the rings properly and evenly.

[@waynevincent892]

The rail looks like it need s be reverse to me

[@doc8579]

Hmmmm…. If your scope is walking backwards/forwards, it’s not securely mounted and accuracy will suffer. Your scope shouldn’t be moving at all.

[@lanceroberthough1275]

No. The force of impulse is from the rail bar into the mount bar is instantaneous thus holding it in place. Since the whole gun then moves with the recoil impulse. The rebound ENERGY DISSIPATES. With the mount to the rear the inertia of the rail moving backwards is caused a tiny delay in the changing of the inertia from its resting position and to movement so essentially it wants to remain in place held only by the mount clamp. This is the reason that it will walk forward. Your test is faulty. Your bullet puller analogy is a false equivalence. Your screws were loose lol. OF COURSE IT WILL MOVE!!!

[@Mrblueridgeman]

I think his engineer friend was thinking about the instance the gun fires (first impulse) but forgot that the gun travels backwards and is stopped by your shoulder. It’s this last “impulse “ that moves the scope backwards.

[@Jeff-mv4yy]

Excellent video. I am an engineer. I'm probably not very good because without any equations, my intuition was that the scope would move rearward, using a similar analogy as your bullet puller. I had gone to those other scope mounting videos that said I was wrong, so I compromised and put one ring to the front of the pic rail and one to the rear. 🤓 I have a lot of gray hair and I can't tell you how many times my calculations and expert calculations did not line up to real world. I put the equations away about 30 years ago when i figured out the guys running the machines had the answers in their shirt pocket for just about anything I wanted to know. Thanks for sharing the knowledge !

[@customgunsammorepairs]

Jeff, Thanks for your kind comments. I’ve found the best engineers to have your philosophy on equations vs real world application. Tim