Missing Rifle Scope Features?

[BjornF16]

Form, on the basis of physics, help me understand why when a manufacturer says they are "shock tested to 1000 or 1500g forces" that doesn't seem to translate to being able to withstand any sort of drop impact. Surely a simple 3 foot drop on a padded mat doesn't cause 1500 g forces, yet the scopes fail predictably fail a drop test. If we remove the marketing of the G forces claims, what the hell do they even mean?

Is that a single g-force application?...or numerous applications added up to 1,000 or 1,500g's?

Got to pretend Bill Clinton is on the witness stand...;-)

 

[Formidilosus]

Form, on the basis of physics, help me understand why when a manufacturer says they are "shock tested to 1000 or 1500g forces" that doesn't seem to translate to being able to withstand any sort of drop impact. Surely a simple 3 foot drop on a padded mat doesn't cause 1500 g forces, yet the scopes fail predictably fail a drop test. If we remove the marketing of the G forces claims, what the hell do they even mean?

Not an engineer. So this is what I understand from speaking with people, and from seeing it and thinking about it.

Usually the “1,500 G’s” is just rearward moment. Sometimes the test forward and rearward movement. In any case, none of them to my knowledge are checking the position of the reticle after each movement to determine if it is still “zeroed”. The general thing is they are put in a machine that simulates 375 H&H recoil for instance for 1,000 times, then pull they scope out look, through it making sure the lenses didn’t break, and maybe spinning the turrets and checking that they still work. Then in “testing” they may put it in a rifle and zero it in. What they are basically doing is seeing if the scope just falls apart- not seeing if they hold zero through that. They ARE NOT checking position of the reticle in relation to a target, nor are they receiving forces of a drop.

Another instance is in the Tanget Theta thread, Tk421 posted videos of “The Shaker” test that TT did on their scopes. Like the recoil testers, it looks really impressive. But think about it- how does that simulate anything that happens with a rifle scope? And, they’re hot checckinh whether the erector/reticle is staying in the same position through that shaking.

What none of these “G forces tests”, shaking tests, recoil tests, etc do- is measure and check that the position of the reticle has not changed in relation to the rifle/aiming point; nor do they account for the fact that the rings attach to the tube, nor that with the scope being attached to the rifle by rings in the middle- the end LW’s of the scope (eyepiece and objective) are now floating and will take nearly all the impact of the drop with the middle functionally being locked in place.


Checking whether vibration or shaking will rattle a scope apart, is not the same as checking its ability to hold zero when mounted to a rifle and dropped. It also does not tell you whether a scope will hold zero on a rifle from actually shooting it. If you want to know whether a scope holds zero from firing, you have to mount it in a rifle, zero it, and shoot it for thousands of rounds and check zero constantly. If you want to know whether a scope will hold zero from a drop- you have to mount it to a rifle, zero it and drop it, then check that it held zero.

There’s a reason that Trijicon has started advertising that at least some of their scope designs (hint) are zeroed and shot for 1,000/3,000/5,000 rounds and checked for zero, as well as zeroed on a rifle and dropped to check zero retention- because that is the only way to know.

 

[Formidilosus]

As of right now, I am standing by my assertion that my comments to this question were on the money. "Or, if generally, such an accidental drop should occur, can we expect to the scope to retain zero and have no mechanical failures?"

And it needs to be clear, that the mounting of the scope and the mounting of the action really, truly have an effect on maintaining zero. How I assemble rifles is specific and for that very reason.

For example- if you take a factory Tikka T3 (which is better at this than most BTW), and have the scope system removed as a variable, using factory torque specs on the action screws (35 in-lbs) on an unbedded stock- a drop from 36” on hard packed dirt will generally cause a .4-.5 mil shift (1.5-2”) at 100 yards. Take that same rifle and totally degrease, threadlock, and torque to 65 in-lbs, and the shift will be .3 mils (1”) or less. And it seems to be about 50%. That is about half the rifles will present no shift when assembled as above (degrease/loctite/torque 65 in-lbs, amd half will have between a .1 and .3 mil (roughly .25” to 1”) shift from 36”. Now, take that same rifle and bed the tang and lug tight, assemble as above, and the shift is not detectable.

 

[SDHNTR]

Gotcha. BTW, you said "hint"! LOL. Please don't go all Big Stick on us!

 

[Formidilosus]

Gotcha. BTW, you said "hint"! LOL. Please don't go all Big Stick on us!

Haha. No. Though, in general the dude shoots and knows. Hint, is because Trijicon isn’t saying that they test every scope before it ships.

 

[Sled]

I've only had 1 scope lose zero resulting in a eviscerated antelope. It was on a trip with my kid to Wyoming and took 2 shots before I realized what was happening. I held windage and put the animal down but it was not a good feeling and was not good for my kid. I re-zeroed the rifle and finished my hunt with no issues since then. I don't recall dropping the rifle and can't recall any of my guns falling more than a "leaned up on a tree" height. In the future, any scopes I purchase will have some level of confidence they will hold zero for mild drops. So, to bring it full circle, dependability is a feature I'd like to see in a scope. I appreciate the testing form is doing and will likely make my next purchase off his results.

 

[ljalberta]

Gotcha. BTW, you said "hint"! LOL. Please don't go all Big Stick on us!

I couldn’t understand half of what that man wrote, but there is no doubt he knew how to drop test (Hint, throw test) and shoot a rifle.

 

[SDHNTR]

Haha. No. Though, in general the dude shoots and knows. Hint, is because Trijicon isn’t saying that they test every scope before it ships.

Dude made me laugh. He came up with some dingers!

I wouldn’t expect every single scope to be extensively drop tested as that would be too inefficient to get them out the door expediently. But I do expect a certain standard that capital ALL their scopes must conform to.

 

[Formidilosus]

I wouldn’t expect every single scope to be extensively drop tested as that would be too inefficient to get them out the door expediently. But I do expect a certain standard that capital ALL their scopes must conform to.

NF checks every scope they sell for impacts, tracking, adjustments, and RTZ. It can be done. And the way they check POI shift from top, back, and side impacts seems to work in real life.

However, you are correct- it seems to be sufficient for most uses for a well executed and designed scope, to be batch tested or checked versus every single scope being checked. It’s why SWFA SS, high end Bushnells, some S&B’s, and maybe some Trijicons for example, can be good and generally are- I do not think they can match another scope line that is having every single scope checked before it ships.

 

[Fartrell Cluggins]

NF checks every scope they sell for impacts, tracking, adjustments, and RTZ. It can be done. And the way they check POI shift from top, back, and side impacts seems to work in real life.

However, you are correct- it seems to be sufficient for most uses for a well executed and designed scope, to be batch tested or checked versus every single scope being checked. It’s why SWFA SS, high end Bushnells, some S&B’s, and maybe some Trijicons for example, can be good and generally are- I do not think they can match another scope line that is having every single scope checked before it ships.

One of the biggest surprises in all of your testing is how often you detect shifts when the gun has ridden in your truck seat. I would think a long ride on a bumpy road in a 4 wheeler would be even harder on a scope.

 

[Sled]

One of the biggest surprises in all of your testing is how often you detect shifts when the gun has ridden in your truck seat. I would think a long ride on a bumpy road in a 4 wheeler would be even harder on a scope.

I believe that's what got my PST. Wyoming two track can be a rough SOB.

 

[Castle Rock]

One of the biggest surprises in all of your testing is how often you detect shifts when the gun has ridden in your truck seat. I would think a long ride on a bumpy road in a 4 wheeler would be even harder on a scope.

Side impact seems to be the issue, guns held in vertical racks don’t seem to suffer as much
I built a gun box for traveling that holds the rifles vertically for this reason

 

[Castle Rock]

Happy to report that I have been bouncing this one on its side a fair bit and so far it is holding a solid zero

 

[Sandstrom]

And it needs to be clear, that the mounting of the scope and the mounting of the action really, truly have an effect on maintaining zero. How I assemble rifles is specific and for that very reason.

For example- if you take a factory Tikka T3 (which is better at this than most BTW), and have the scope system removed as a variable, using factory torque specs on the action screws (35 in-lbs) on an unbedded stock- a drop from 36” on hard packed dirt will generally cause a .4-.5 mil shift (1.5-2”) at 100 yards. Take that same rifle and totally degrease, threadlock, and torque to 65 in-lbs, and the shift will be .3 mils (1”) or less. And it seems to be about 50%. That is about half the rifles will present no shift when assembled as above (degrease/loctite/torque 65 in-lbs, amd half will have between a .1 and .3 mil (roughly .25” to 1”) shift from 36”. Now, take that same rifle and bed the tang and lug tight, assemble as above, and the shift is not detectable.

Do you have any pictures or details on how you bed a factory Tikka stock?
Thanks,
Ryan

 

[Formidilosus]

One of the biggest surprises in all of your testing is how often you detect shifts when the gun has ridden in your truck seat. I would think a long ride on a bumpy road in a 4 wheeler would be even harder on a scope.

Yes indeedy. I have said before that I could basically forgo most everything else, just zero a scope and put it in in the truck vault on cardboard and drive mountain forest service roads for a day and check zero at the end. I used to live where it was just over two miles to the shooting spot, and the vast majority of scopes would lose zero every single time driving up or down that road. However, vibration like that is only one part.

 

[Castle Rock]

Do you have any pictures or details on how you bed a factory Tikka stock?
Thanks,
Ryan

Tikka bedding

 

[Dioni A]

Anyone else get the impression that tract was pandering with this post and not really interested in improving their product line?

 

[260madman]

Anyone else get the impression that tract was pandering with this post and not really interested in improving their product line?

I have a thread about their new hunting scope and how they missed the mark after starting this thread. I think they were looking for confirmation in what they brought out because it was finalized at that point and no turning back. I ranted. I kept it PG rated.

 

[Pocoloco]

Ultralight reliable sub 12 ounce scope

Our nikons 3-9x40 track reliable and in at 13 ounces, but I want to upgrade to a zero stop. Looking at nightforce 2.5-10x42 but 20 ounces and a couple dollars… wish they had a reliable zero stop, lighter

 

[Pocoloco]

It’s a bit more involved than that. Tasco never made anything, just like the vast majority of companies now, they contract from the manufactures to make what they sell. The Tasco SS was made to compete in a Navy sniper optic trial- it won. Eventually when Tasco went under SWFA bought the rights to them and improved them. Any of them but the original fixed power “Classic” scopes are SWFA’s creations.



People always believe they need huge power. You don’t. Not only is it not required for medium to long range on big game, it causes way more problems than it solves. The problem is people spend their time shooting groups on paper at 100 yards and believe that translates to field shooting animals. Spotting your impact/splashes/or misses through the scope is WAY more important than some visual comfort gained with high magnification. If you can see it in 8x or 10x binos, you can kill it with a 10x scope… and you get the added benefits of seeing more, reacting quicker, with a larger eyebox and longer eye relief.

I prefer 3 power at 300 and 5 power at 500…etc. so a 10 power is more than enough for hunting and I would like you not likely take a shot on an animal at 10 power. Wonder why nightforce doesn’t embrace FFP. Still considering upgrading our current scopes to this one to add zero stop.