Inclinometers / bubble canting devices. worth it for long range rifle shooting, is plumb line enough?

want2learn

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Minuteman
Sep 7, 2013
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Hi, just starting out to learn longer range rifle shooting. Working hard at developing my skills, reading a lot. Maybe 300 to 1000 yards. I've got two rifles, a little older but both in really good shape.

I was wondering if its worth purchasing inclinometers and bubble canting devices for my .308 rifle. One rifle is a Tikka .308 and uses proprietary optilock rings so there's no space to mount anything except onto the scope itself. The other rifle is a Sig ssg3000 and my scope is mounted on a fixed unit american defense mount so there is only just a little rail left.

If you feel they are important adjuncts would you be kind enough to list specific makes and models to look for.

Cost as always is a real factor but i don't want to buy garbage.

One other related question....is it enough to orient the scope reticle to a plumb line... does putting a bubble level on the rail add any more accuracy to the scope alignment and mounting?

I really appreciate your help, insight and recommendations.
 
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Want,

long range shooting demands a level (IMO) , hell you can't even trust your tall target test without one.... the level is oriented to the scope not the rifle... if it works to the rifle fine but if your shoulder pocket wants to the cant the rifle let it. but level the scope.this has been well documented here on the hide but look it up. inclinometer could be useful but you have to figure how you put inputs into your ballistic solver. at 1K or under anything under 15 degrees, with a flat shooting cartridge is a no problem at 15 you need to correct for angle. many phone/ipad/other ballistic platforms will have a measuring method and just take that slope measurement and input your you ballistic calculator and run.
Idahoorion
 
wow thank you. i really appreciate it...I will look for a scope mounted bubble level.

will try to search outa ballistic platform for my iPhone....will it also calculate the angle of inclination/declination?
 
wow thank you. i really appreciate it...I will look for a scope mounted bubble level.

will try to search outa ballistic platform for my iPhone....will it also calculate the angle of inclination/declination?

The iPhone has an inclinometer app built in. It's part of the compass. Also get a slope doper for a no battery solution. Works every time. Get a bubble level that goes on the scope.
 
thanks...i didn't know that the iPhone had that function. I think i will finally get to the range today. will try it out. Saw that Mr. Tubb has a bubble scope level but its a bit expensive, got to shop around a bit more. There are some cheap ones on amazon that seems to have received very good reviews.
 
thanks...i didn't know that the iPhone had that function. I think i will finally get to the range today. will try it out. Saw that Mr. Tubb has a bubble scope level but its a bit expensive, got to shop around a bit more. There are some cheap ones on amazon that seems to have received very good reviews.

Don't cheap out. I highly recommend the accuracy1st bubble level. It uses a bead and isn't subject to heat affecting the bubble
 
Watching thlr YouTube videos, the Norwegian dude, he demonstrates your perception looking a scope is a more sensitive level than a bubble level. My experience too.
 
Here is why you need it. I'll write this so anyone can understand it, even the math challenged. It's based in Trig and Calc. so I'll keep it simple.

Imagine a clock with one inch hands. All of them are one inch long. The clock face is a rigid grid with the center (0,0) being the point from which the clock hands radiate. Now when the clock is at, say, 1.30, then the hour hand will be pointing at 45deg. The location on the grid here is Sqrt.(2)/2, Sqrt.(2)/2, or "root two over two". The x coordinate will always be your cosine. The line of sight is the hypotenuse of the angle and consists of components of both the sine and cosine. You aren't interested in sine values usually, gravity takes care of that. But at an angle, you want to shoot the COSINE distance, NOT the line of sight distance! The cosine will always be a fraction and will always render your distance "shorter". Actual distances are calculated thus: Line of Sight Distance x cosine (of the angle) = Actual Distance to target to dial in. Line of Sight Distance is only the SAME as the Actual Distance when the cosine is 0 (and you are perfectly level to the target).

The farther away you are from the target, the more all this matters. I still use my TI89 calculator, but I'm gonna get one of those CONX laser range finders/Kestrel weather and ball. comp. soon to outfit a nice spotting scope with. And of course a couple ACI's. Bader and Era-tac make some I'm interested in. I think Badger has one of the better offerings for the price, I like the one that fits on the rail under the scope.

Incidentally, two cosine indicators would work better-- One mounted normally, the other mounted perpendicular (90deg. to the other one). This will give you the cosine values of two axes instead of one. When the second cosine indicator is at "0" then the rifle is perfectly level horizontally. Now keeping both on a rifle may be a bit much, but having one to use for adj. your reticle to a plumb bob would be nice. More accurate than a bubble level, but more of a pain to make it work. More junk hanging off the rifle.

I saw some device --could have been build into one of those digital scopes?-- that does exactly this, and combined with the ballistics computer, it gives you the corrections. Wish I could tell you who had those, what they were, but I can tell you they'll be costly.

An ACI and that CONX setup seem to be the most user friendly and cost effective way of doing all this.

I feel the ACI, for BOTH planes, should really be a standard to all scopes by now, the technology is there to build them into the optic itself such that it's in view, say somewhere at the bottom of the reticle or the very top. Should be standard on high end, long range scopes and as an option on others. Doesn't need to be digital either. Just building one onto the scope itself would be nice too. But they'd have to get it right at the factory or it would be nothing but problems.
 
While cant is important, watch this https://www.youtube.com/watch?v=iChDlTNmk0I and then decide if you think a bubble is more accurate than the human sensory perception. Especially if you are shooting a timed exercise, moving targets, etc. To setup the scope on your rifle, nothing will define "level" better than a plumb line; but then you need something to assure your rifle is plumb as well.I use a couple of cheap 1" bubble levels placed at a couple of points to assure a consistent reference.

For inclination, all of the ballistic phone apps I have seen have a built in capability to "sight" the incline and make a suitable adjustment for vertical.