I think I might be going a tad overboard... but if I'm going to be working on Gunday, I am using some of my cycle time to play
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The scope has anti-tilt "bumpers" that warn you if you are past a threshold that you can set in the accompanying app, so I figured I want it pretty square. I don't usually use the scope with the illumination (and thus the BDC and all the other features) but I'm really still in the load development phase shooting almost entirely at 100 yards. In this case, with upper reciever bottom to top scope cap as my datums I'm out about .0005 over 3". Probably close enough.
I think the parts on the table behind my upper will be of some interest to those here, they are components of a system that mounts to the new JLTV (replacement humvee) and supports an M230 chain gun and a battery of sensors to detect and destroy small commercial drones - apparently before being bombed out of the 24hr news cycle, ISIS was using them in lieu of bomb vests. In tests it scored kinetic kills (direct hits) out to a half mile
05-26-2019, 06:42 PM (This post was last modified: 05-26-2019, 06:46 PM by rabiddawg.)
I set the rifle in a vice or holder and use a bubble level to get it level. Then I hang a plumb bob in front of my door. Then shine a flashlight from the objective end of the scope to project the reticle onto the door. Focus it by using the reticle focus ring. I put another level on the scope turret just for reference. Then I turn the scope until the vertical line and plumb bob are aligned. Snug down the rings and double check before torquing them down.
Knowing everthing isnt as important as knowing where to find it.
rabiddawg Wrote:I set the rifle in a vice or holder and use a bubble level to get it level. Then I hang a plumb bob in front of my door. Then shine a flashlight from the objective end of the scope to project the reticle onto the door. Focus it by using the reticle focus ring. I put another level on the scope turret just for reference. Then I turn the scope until the vertical line and plumb bob are aligned. Snug down the rings and double check before torquing them down.
That makes sense. That way you don't have to assume the scope turret cap is square to everything else. Just to satisfy my curiosity, do you ever come across a scope where you level against the plumb and get bad results from the level when you do your sanity check?
What I do for the ar now is I have a magpul pic rail mounted on my bench. I attach the one peice mount too it and torque it down. Then install the scope into the rings, put a bubble level on the elevation turret and level it, then tighten and torque down.
Remove from bench, install on rifle and never look back.
The only problem I have is making sure I tighten down the rings equally. If you go too far on one side it can cant the scope in the mount. I use a torque screwdriver and start way low.
Knowing everthing isnt as important as knowing where to find it.
rabiddawg Wrote:The only problem I have is making sure I tighten down the rings equally. If you go too far on one side it can cant the scope in the mount. I use a torque screwdriver and start way low.
yes. Use a torque wrench.
Back and forth on the screws, cross-over and back X-patterns, little at a time. watch the bubble level on the scope as you tighten each screw by each amount.
Also, I first do one ring, one pair of screws, to get it level and snug. then the other ring, one set of screws likewise. once both pairs of those are snug, do a "catch-up" on your remaining screws... then do the back and forth, cross over method a little at a time for all screws. Keep the bubble centered.
IIRC the bubble tends to move slightly away from the one you are tightening.
"Down the floor, out the door, Go Brandon Go!!!!!"
Put the gun in a rest, level the top Picatinny rail with a bubble, then rotate the scope in the rings until the vertical reticle lines-up with a plumb line downrange.
You can take a plumb line to the range you use regularly and confirm a permanent vertical structure downrange is plumb. Then use that to check scopes from then on - target frames, flag poles.
I use a 1m length of white PVC pipe suspended with a weight below it as a plumb line instead of string as it's easier to see without having to crank up the magnification.
I have an Arisaka optic leveling wedge set. It's great for quick painless leveling between the scope body itself and the optic mount or rail. It forces the body of the scope to be level in relation to the counterpart only, so I also use a bubble level and a known plumb line - in my case I go to the range with my tools and level the vertical reticle leg to the radio tower behind the target berms and set the level. That way, when the level shows plumb, I know I'm right, regardless of the position of the rifle. It gives me piece of mind that I'm not relying on the turret top to be perfectly perpendicular to the actual reticle, which while close, may or may not be as accurate as I want. We found that even a Khales 318 we tested was off a tad.
There are lots of top tier shooters that advise against using the top of the turret cap as a reticle level simply because some optics makers aren't machining the turret cap to be square, rather they focus on making sure the erector is correct, and the turret cap being perfect is an afterthought. I wonder if they're even tested to be in most lower priced optics.
Nothing kills the incentive of men faster than a healthy sense of entitlement. Nothing kills entitlement faster than a healthy sense of achievement.
05-31-2019, 10:42 PM (This post was last modified: 05-31-2019, 10:45 PM by centerfire.)
Scope caps are not square to the erector or the reticle. Square the bottom of the scope to the mounting base (Pic rail in this case), I use feeler gages but there's tons of ways to do it including a deck of cards. Once the scope is square to the rail go shoot the rifle. Scope mounted bubble levels are largely worthless and a waste of time. If you're concerned the reticle isn't square to the erector you'll need to shoot a tall target to tell how far out it is (unless it's visually noticeable).
The level isn't necessarily for leveling the reticle, it's to ensure that the sight radius from your point of aim is plumb to your bore axis. This matters, but just as you say centerfire, if the scope is square to the mount then you should be good to go.
Nothing kills the incentive of men faster than a healthy sense of entitlement. Nothing kills entitlement faster than a healthy sense of achievement.
Kswhitetails Wrote:The level isn't necessarily for leveling the reticle, it's to ensure that the sight radius from your point of aim is plumb to your bore axis. This matters, but just as you say centerfire, if the scope is square to the mount then you should be good to go.
That wasn't what I was talking about but since we're on the subject, the plumbline is a waste of time too. How many AR uppers have you seen with a canted Pic rail? How about an R700? The only instance I can think of where the bore didn't match the base was a Remington with a receiver warped like a banana and you could see it with the naked eye. There is all kinds of scope mounting mumbo jumbo, and like everything else in shooting, it's over thought and makes no difference on the target down range. Again, level the scope to the base and shoot it.
centerfire Wrote:Scope mounted bubble levels are largely worthless and a waste of time.
Why is that?
centerfire Wrote:If you're concerned the reticle isn't square to the erector you'll need to shoot a tall target to tell how far out it is (unless it's visually noticeable).
I bow to your wisdom here Centerfire. Obviously I'm doing it wrong.
Here's the fun part. If your axis to axis distance is what it is on an AR - 2.7" or thereabouts - and you're off 2 degrees, (you cant tell me you can see that under pressure); then you're off a few inches windage AND elevation at distances greater than 400. And it compounds further out. You're saying that you're going to go shoot at distance with a possible 2-3 tenths error, account for wind, environmental, and the nagging time limit, and still confidently hit your targets? I call Oscar Mayer sandwiches.
It's even less of an issue on bolt guns because the radius from bore to sight planes is smaller. Still - I don't know any truly competitive shooter that would tell you leveling your optic, and having a visible level to look at under pressure is a bad idea, or as you put it, stupid.
Do I have a level on my hunting scope? Nope. Because at hunting distances it really doesn't matter. All my competition optics do though. If I dial, it does. If I plan on shooting over 300, it does. Because it's smart, easy, and reliable.
Most folks do overthink these things. But, the process of overthinking and overcoming is how we advance and find our own way. Your optics erector MUST be plumb, or you're not dialing true elevation and windage. If you're moving a point of aim upward and sideways without realizing it's doing so, good luck on figuring that out on the bench...
Tall target test? I actually laughed at this one. Mount your rifle, and go shoot a plumb line to check your elevation clicks? Does that tell you your optic is off, or that you've mounted it off? Or that your rail is off? Or that you're not getting back in position between shots? Or that you're holding the rifle plumb? Here's another problem with your points. What do you do if you mount your optic into a mount that isn't square? Or if the rail is off? (yes sir, it does happen) If you're not going to use a level to ensure you're not canting your rifle, how would you ever know the mount is the problem?
You MUST level and plumb the erector. You MUST level the rifle with the optic mounted. Not mostly, not "good enough" - it MUST be true. Dead on. Otherwise all the testing in the world is pointless as you have variables you're unable to account for. Good luck chasing that rabbit down it's hole.
Nothing kills the incentive of men faster than a healthy sense of entitlement. Nothing kills entitlement faster than a healthy sense of achievement.
06-01-2019, 09:07 PM (This post was last modified: 06-01-2019, 10:52 PM by Sinclair.)
Chapter 12, pg 173 - 183, "Long Range Shooting Handbook, A beginner's guide to Precision Rifle Shooting" by Ryan M. Cleckner, Esq. $24.95 and 25% of the proceeds of this book will be donated to these two military charities: Special Operations Warrior Foundation and SUA SPONTE Foundation.
"A Patriot must always be ready to defend his Country against his government"
Edward Abbey
"Stay out of trouble, Never give up, Never give in, Watch you're six, Hold the line, Stay Frosty."
Dr. Sabastian Gorka, Hungarian by birth, American Patriot by Beliefs.
06-02-2019, 01:30 AM (This post was last modified: 06-02-2019, 01:39 AM by Klem.)
centerfire Wrote:Because if you're holding the rifle canted enough to create error in your dialed elevation you can visually see the reticle is canted.
If it's a gross cant, sure, but a subtle one you might not notice. I use a bubble on my long range rifle and I am convinced it helps.
There's dozens of youtube videos on the subject.
Was wondering whether you had some alternate take on the test given your strident beliefs are at odds with others.
The idea of squaring a scope by its reticle (plumb line) or squaring a scope by its body (base or top cap) are both based on assumptions.
Those advocating using a plumb line assume the reticle is exactly square with the erector mechanism.
Those advocating using the flat base assume the base is exactly square with the erector mechanism.
Neither is guaranteed and I agree, the only way to prove either assumptions is to square and zero the gun and then carefully dial up the scope to check for any cant in the group. That includes your preferred method.
I once returned two Leupold MRT compacts as both reticles were about 11 O'clock/5 O'clock to the dials and square base. Clearly out of the box something was wrong. If that can happen then smaller errors, not so obvious to the eye are probably out there.
I would appreciate if you would not infer others are stupid simply because they do things differently to you. By all means lets have a debate but the degree of troll in you had a mod intercede on another thread and it just pollutes the goodwill we have for each other. Have a little more respect please.
Klem Wrote:Was wondering whether you had some alternate take on the test given your strident beliefs are at odds with others.
The idea of squaring a scope by its reticle (plumb line) or squaring a scope by its body (base or top cap) are both based on assumptions.
Those advocating using a plumb line assume the reticle is exactly square with the erector mechanism.
Those advocating using the flat base assume the base is exactly square with the erector mechanism.
Neither is guaranteed and I agree, the only way to prove either assumptions is to square and zero the gun and then carefully dial up the scope to check for any cant in the group. That includes your preferred method.
I once returned two Leupold MRT compacts as both reticles were about 11 O'clock/5 O'clock to the dials and square base. Clearly out of the box something was wrong. If that can happen then smaller errors, not so obvious to the eye are probably out there.
I would appreciate if you would not infer others are stupid simply because they do things differently to you. By all means lets have a debate but the degree of troll in you had a mod intercede on another thread and it just pollutes the goodwill we have for each other. Have a little more respect please.
I'm sorry you agree with me, that's gotta be hard for you.
I have an entire shelf filled with crap that people who claim to be smart convinced me I couldn't live without. When did mastering the fundamentals become so unpopular? I'm guilty of trying to buy my way in too. Not that I need Frank's opinion to know a worthless shiny trinket but here he takes on bubble levels: https://forum.snipershide.com/threads/do...l.6935344/
Kswhitetails Wrote:I bow to your wisdom here Centerfire. Obviously I'm doing it wrong.
Here's the fun part. If your axis to axis distance is what it is on an AR - 2.7" or thereabouts - and you're off 2 degrees, (you cant tell me you can see that under pressure); then you're off a few inches windage AND elevation at distances greater than 400. And it compounds further out. You're saying that you're going to go shoot at distance with a possible 2-3 tenths error, account for wind, environmental, and the nagging time limit, and still confidently hit your targets? I call Oscar Mayer sandwiches.
It's even less of an issue on bolt guns because the radius from bore to sight planes is smaller. Still - I don't know any truly competitive shooter that would tell you leveling your optic, and having a visible level to look at under pressure is a bad idea, or as you put it, stupid.
Do I have a level on my hunting scope? Nope. Because at hunting distances it really doesn't matter. All my competition optics do though. If I dial, it does. If I plan on shooting over 300, it does. Because it's smart, easy, and reliable.
Most folks do overthink these things. But, the process of overthinking and overcoming is how we advance and find our own way. Your optics erector MUST be plumb, or you're not dialing true elevation and windage. If you're moving a point of aim upward and sideways without realizing it's doing so, good luck on figuring that out on the bench...
Tall target test? I actually laughed at this one. Mount your rifle, and go shoot a plumb line to check your elevation clicks? Does that tell you your optic is off, or that you've mounted it off? Or that your rail is off? Or that you're not getting back in position between shots? Or that you're holding the rifle plumb? Here's another problem with your points. What do you do if you mount your optic into a mount that isn't square? Or if the rail is off? (yes sir, it does happen) If you're not going to use a level to ensure you're not canting your rifle, how would you ever know the mount is the problem?
You MUST level and plumb the erector. You MUST level the rifle with the optic mounted. Not mostly, not "good enough" - it MUST be true. Dead on. Otherwise all the testing in the world is pointless as you have variables you're unable to account for. Good luck chasing that rabbit down it's hole.
Maybe you just need to practice more so you stop holding your gun crooked? :ohsnap!:
