Rifle Scopes Setting up Anti Cant Device?

[mram10]

I setup my rifle on the bench and leveled the action. I then leveled the crosshairs on the scope to match a distant horizontal roof. Now, here is the big question.

I look down at the ACD and the bubble is centered, but when I get behind the rifle, the bubble is no longer centered due to my head position.

I assume it is better to center the ACD with head behind the scope. What do you gentlemen do?

 

[tickled pink]

Re: Setting up Anti Cant Device?

What I did was to put a wood dowel in the end of the barrel so it sticks straight out without drooping. then I put a level on top of the dowel and adjust the rifle so the dowel & bore is level. When this is accomplished I adjust the ACD to zero and then the job is complete. The important thing is to get the bore and ACD parallel to each other then as you tilt the rifle up or down the ACD will give you the angle of the bore.

40gt

 

[JC Steel]

Re: Setting up Anti Cant Device?

as long as your gun is level, your scope is level and your Anti cant device is level to those than thats fine. If your head or body pushes soemthing out of level than that is another problem. It sounds like everything is level though. Just go with it. Practive shooting when the bubble is level. It might take some getting use to because over time you have probably pushed the gun one way or another to make it un level. Make sense?

 

[bward]

Re: Setting up Anti Cant Device?

I recently bought an USO rail mounted level and have noticed that when I get behind the rifle and use the level the reticle appears to be canted. It appears this way on both my Premier and Hensoldt so I know the reticles are not actually canted. What is causing this appearance?

 

[christian77]

Re: Setting up Anti Cant Device?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bward</div><div class="ubbcode-body">I recently bought an USO rail mounted level and have noticed that when I get behind the rifle and use the level the reticle appears to be canted. It appears this way on both my Premier and Hensoldt so I know the reticles are not actually canted. What is causing this appearance? </div></div> I have heard that a some USO level mounts were machined poorly & the level sat at a tiny bit of an angle causing a problem like this.

I read about it on here and have no personal experience with this problem since all of my USO levels have been fine, but perhaps that is the culprit (at least for bward)?

 

[bward]

Re: Setting up Anti Cant Device?

Mine was off, but I shimmed it so that it was level with the action and the scope. I am guessing the reticle just looks different to me because I am used to holding the rifle slightly tilted instead of level. Just looking for confirmation.

 

[clmayfield]

Re: Setting up Anti Cant Device?

I am trying to understand your question. For mounting the ACD:

Here is how I do it. First, I attach my scope to the rail using the feeler method. Then, I set up a plumb bob about 50 yards away and I make sure my reticle is leveled. Then, I attach my anti-cant to the scope with a ring. Usually, it is an iterative process because as I tighten down the scope ring, the device stops being level, so I have to loosen it to do it again. I have found that using better rings makes this process go smoother.

If you have a rail-mounted anti-cant device, then it should automatically mount level. If the bubble is off when you shoot, it is because you are off, not the device.

If you are asking when to level the rifle, the answer is once you are behind the rifle. Leveling before you are in the shooting position is useless because once you load the bipod, that position will be off. I use a really sensitive Level Grouse for paper work and I will start to cant my rifle just after running the bolt (I think the force of actually chambering the round cants the rifle to the right a little). I am in the habit of shooting and then using my cheek and non-firing hand to cant the rifle back to the left after each shot for slow fire. For fast fire, I just live with the fact that I am not going to be able to be as careful.

 

[shooter19802003]

Re: Setting up Anti Cant Device?

wrong thread

 

[mram10]

Re: Setting up Anti Cant Device?

My point is this:
Everything is level and centered when it is in the vice. However, when I get behind the rifle, the bubble does not APPEAR centered. It is either centered as you look at it from behind the scope, or it is centered when you look from above, but not both.

Hope this clarifies it a little.

 

[sobrbiker883]

Re: Setting up Anti Cant Device?

I'd go with setting it (if the rest is known to be level and the scope is plumb) for appearing level from behind the rifle.

More often than not that is where you will be firing from I'd venture.....

 

[mram10]

Re: Setting up Anti Cant Device?

Makes sense SB. It is just easier in the vice.

 

[Macdaddy]

Re: Setting up Anti Cant Device?

mram,

I found the same thing with my Heritage but came to accept that it's me. My instructor (who is very well known and respected in this field) told me that a significant number people mount their rifles with a cant unless they have something like the bubble to tell them to do otherwise. It's just a habit one has to learn to break. He even admitted that when he first used an anti cant device, he was amazed at how far off he was from level.
Having said that however, my USO ACD is a little off center too even when the rifle is level. Mine is a rail mount and is the type that swings out of the way. My bubble actually changes a little as I swing it out because I think it actually goes a little beyond the 90 degree perpendicular position. Just something I have to keep in mind. Not sure what the fix would be for that except send it back but they may all be that way.
Would be curious as to whether the bubble is centered when you look through your scope at the distant roof line and your horizontal is level? If not, it would seem your bubble is off.

 

[427Cobra]

Re: Setting up Anti Cant Device?

I had a USO rail mounted level and IMHO there OK, my 260 has a Tubb ACD mounted on the barrel just aft of my Muzzle Brake, with the scope removed I put a level on the scope rail, level the weapon then lock the Tubb ACD down in the level position, I level my scopes with the feeler gauge method.

 

[Hellbender]

Re: Setting up Anti Cant Device?

You are getting parallax from your head position (eye) not being perfectly square with the bubble.

Level it from your shooting position.

 

[mram10]

Re: Setting up Anti Cant Device?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Hellbender</div><div class="ubbcode-body">You are getting parallax from your head position (eye) not being perfectly square with the bubble.

Level it from your shooting position.</div></div>

That makes sense. Just wanted to make sure you guys agreed.

 

[ronas]

Re: Setting up Anti Cant Device?

I had the same or similar problem with the USO swivel rail mount level. I could not get it to function properly so I returned it. The vendor Optics Planet even emailed me a link where I could download a return shipping label at no cost to me. Below is what I told Optics Planet in the comments section.

<span style="font-weight: bold">There is too much freeplay in swivel for item to maintain indicated level position. Please see below.

The item is defective because the bubble level capsule will not achieve level because there is to much freeplay in the swivel. If I tighten the swivel knob tight enough for there to be no freeplay it will not show level. If I loosen the swivel knob to have the capsule show level then it has excessive freeplay and a repeatable level can not be obtained.

I know problem is with item because I attached my bipod, which can be canted one way or the other to the rifle, then placed rifle on level workbench. Next made sure the picatteny rail was level in the area where the quick release mount is located, then checked to confirm the scope attached to the quick release was also level. Everything was level on my end. With this being the case the bubble level should be able to show rifle is level and not canted one way or the other. The excessive freeplay in the 45 degree swivel will not allow a repeatable level read on the bubble capsule.</span>

 

[George63]

Re: Setting up Anti Cant Device?

too many variables for an anti cant level that attaches to the rail, to be right on a given rifle. When they attach to the scope with a separate ring it is so easy to fine tune it by picking which side to tighten. If you really want to use a fixed mount (non adjustable) anti cant level you may be able to remove the lines with solvent or scraping, set everything up perfectly level and remark the bubble with paint (use a fine wire to apply the paint) I have done this on carpenter levels with some success