Scope Level

Which one? I will be ordering one today or driving to SWFA to pick one up. They are a relatively inexpensive part of the rifle so I'm not looking much at the prices. I just want the one that will reliably keep me level without breaking position. 30mm tube. LH

JEC makes the best one around, but I don't think you can go pick one up today. It is an invaluable tool for shopting as well as mounting scopes. I rely on it to hold the rifle level while I line up the scope reticle to a known level line. The tube mount type anti-cant levels require you to get the rifle level with a level on the pic rail anyways, level the reticle, then level the spirit level. That is a too many extra steps in my opinion. The JEC is tool-less to remove from the pic rail, so I move it to what ever rifle I am shooting.

In second place is the U.S. Optics pic rail mounted level. It is the same design as the JEC but you will need to confirm its' calibration. Attach it to the pic rail, place an additional torpedo level on the rail and see where the bubble rides in the tube. For instance, the U.S. Optic level I have, I have to make the right side of the bubble touch the right line as opposed to keeping it perfect center. The U.S. Optics model may very well be in stock at various locations.

I really like to mount scopes when I can set up outside in the back yard....so I can get out of the cramped work space in the shed....and use the neighbors roof gable where it meets the chimney to a get a nice 90* angle 2 line joint about 50 yards away....good thing he is an absentee owner...but I did freak out one of his Weekend Renters one time that showed up early...

Turned out he understood what I was doing after his wife calmed down, and came over to watch and yak about rifles. Really enhanced my relations with the neighbor... He shoulda helped his kid buy my place 2 years ago when he said he would...and bailed on the deal without ever telling me.
Ron

Are the Knights armament rail mounted levels any good ?

I have no personal experience with them. Any model purchased, I would verify calibration before using it as an anti-cant.

I use the levels that attach to the tube of the scope. All you have to do is line the recticle up with a plumbob of some sort then put the bubble of the cant level wherever you want it and tighten it down. Level the rifle and level the scope on the rifle with the cant level. Once the level is correctly positioned in accord with the recticle and the rings, they stay on the tube even if I change the scope to another rifle.

How do you know you kept the rifle level once the scope is over the pic rail?

If the pic rail is level with the action, it makes no difference what angle the rifle is when I change the scope from one to the other because my level, reticle, and the bottom of the rings are all in agreement with the plumbob. To put it another way, I can level the reticle with the anti-cant before I even put the scope in the rings... Of course you are right that in the initial set up it is necessary to use a second level to level the rifle. If you think about it, the recticle being level is way more important than the scope being exactly over the barrel.

Not correct.

With a 1 1/2" to 2" sight offset (center of the scope to center of the bore) canting causes left to right error on target. The farther the shot, the more elevation dialed in, the more this is magnified. A one degree cant error at 100 yards may not be seen, but at only 500 yards with 2.0 to 3.5 Mils dialed in, (depending on BC and MV) it will be come apparent. So it is inportant that the scope is as close to exactly over the barrel as possible.

Go search the rifles section where I shot the sideways rifle (90 degrees of cant) and see how much I had to dial to get the scope zeroed at 100 yards.

Think about it, it doesn't magnify... The reticle offset magnifies, but as long as the reticle is level, the barrel offset stays constant.

When you turned your rifle over to shoot 90 degrees, if you rotated your scope to perfect verticle, your POI would then be a constant 1 1/2" or whatever to one side of your original POA, no matter what the distance...

It does magnify at distance. It is triginometry. Add to that the two arcs you are trying to make meet on the target. Those being the verticle due to gravity and the horizontal arc due to windage. Think about how 1.0 Mil at 100 yards is 1/10 of a yard (3.6") and how 1.0 Mil at 500 yards is 1/2 a yard (18"), and 1.0 Mil is 1 yard (36") at 1000 yards. All are 1 Mil, and all are magnified the farther your target is. Cant the scope OVER THE RIFLE 1 degree at 100 yards and it is not as significant as 500 yards. Especially of you are dialing elevation. A right handed shooter tends to cant counter clockwise, so you will have an impact left of center of the target at distance when canted.

That is also false.

You forget that you have built in compensation for gravity at 100 yards when you zero. The bullet is falling as soon as it leaves the barrel. We make the sight picture and the bullet path meet in space at a determined distance and call it zero. Turning the rifle sideways you now have a sight offset problem as well as a gravity problem. Windage knob becomes elevation, and vice versa. If I remember correctly (I wrote this down and stored it in the stock pack) I have to dial the windage knob (now elevation) .9 Mil to get the bullet back up to the center of the scope due to gravity. And elevation (now windage) .4 Mil to compensate for sight offset.

We're talking apples to oranges. You didn't turn your scope 90 degrees back to vertical when you turned your rifle 90 degrees or the drop would have already been compensated for. The anti-cant is useless unless it is reading "level" when you shoot. You used the horizontal for vertical which is not what I am saying.In your case, you had to ignore the anti-cant. I am saying the anti-cant level needs to be in accord with the reticle first and foremost, because if the reticle is canted, it will affect the POI much more than if the scope is slightly to one side or the other of the barrel's centerline. With all that being said, there is no reason not to get the scope centered as correctly over the barrel as possible, but far more important thing is to have the reticle truly vertical and that is the purpose of the anti-cant level.

Still wrong.

And I'm done repeating myself.

You'll eventually figure it out, if the bullet is always falling straight down and if the reticle is straight up and down it will always track the bullet's trajectory correctly... If it takes .1 mil to correct the horizontal, that .1 mil will correct it no matter what the distance. Wind correction will be the same as you would normally calculate it. If you have a base that is not horizontal to the barrel (20 moa offset) all bets are off...

Pretty sure I have it figured out.

It's not worth arguing over, we all agree to get everything as close to level as you can. The theory about one being more important than the other is just an interesting sidenote for me...

Sounds like y'all need to meet up and put the apples and oranges to a test. I'm sure y'all come up with a friendly understanding.

I'd do that, but I'm a lousy shot...

This is a good read about the subject of getting not only level but correctly aligned with the bore

http://www.longrangehunting.com/articles/reticle-alignment-1.php

http://www.horizonfirearms.com/products/accessories/zerolight.html

I use a Segway to level the rifle and the level that goes on the scope from the Wheeler Level Level system. That works ninety percent of the time. Occasionally you run across a rifle with no flat surface for a level and sometimes the turrets on scopes are not level, or you have the situation with both scope and rifle. When that occurs I use a Reticle Tru,

http://www.amazon.com/Segway-Reticle-Lev...reticle+leveler

http://www.cabelas.com/product/Wheeler-reg-Level-Level-Level/728535.uts

http://parabola-llc.com

I went with the U.S. Optics

http://www.midwayusa.com/product/629842/...=ProductFinding