Leveling an action before leveling a scope.

[PatMiles]

ARC nucleus action with a scope rail that attaches with torx screws so I am not positive the action can be leveled using a machinist level across the rail. Any other procedures to use?
I'll be shooting F class so I want to remove any cant for obvious reasons.
Thanks,
Pat

 

[BoydAllen]

I would probably set it up using the base and then do a tall target test. Or if you can find one, or have a friend who has one (as I do) this will get the job done.
https://www.brownells.com/gunsmith-...ers/vertical-reticle-instrument-prod6097.aspx
It puts the CL of the scope over the CL of the barrel. You can then roll the scope so that the vertical cross hair is parallel with a plumb line.

 

[Delfuego]

I use little bubble levels on the action. I have the Wheeler kit and some other little ones, plus I run US Optics picatinny rail-mount bubbles. I get the action/rifle nice and level and then use a plumb-line for the scope.

 

[Ned Ludd]

ARC nucleus action with a scope rail that attaches with torx screws so I am not positive the action can be leveled using a machinist level across the rail. Any other procedures to use?
I'll be shooting F class so I want to remove any cant for obvious reasons.
Thanks,
Pat

I looked at a picture of this action/rail and there is not a good way to ensure that the top of the scope rail is perfectly parallel to a tangent line of the body of the scope, or exactly how it sits in the stock; I assume this is what you are asking. For shooting F-Class, I think you're completely safe to level using the top of the scope rail before installing and leveling the scope itself.

 

[dmoran]

From a leveled rifle/stock, adjust the scope rotation in the rings until the reticle is square/parallel to a plum-line hanging at distance.
Using levels only, or leveling off anything else, will not guarantee a square/parallel alignment. Reasons being:

• Action's are not always truly squared in the stock.
• Rings and bases are not always truly squared to the action.
• Turrets are not always truly inline to the reticle.

Myself use levels from the action & base to get close/roughed-in, then final alignments as described above, at 100yds.
My 2-Cents

 

[powderbrake]

I use a level on the top of the rail as a starting point, after I am sure there are no burrs on the rail where I place the level.

If you are doing it at home, I find that setting up on a bench, with the Wheeler kit, and sighting out the back door to a house a 100 or 200 yards away gives me a good reference. (Please do this with the bolt removed).

Siding is generally horizontal, as are window frames. The building corners and window frames are vertical.

 

[PatMiles]

Thank you sir.

I looked at a picture of this action/rail and there is not a good way to ensure that the top of the scope rail is perfectly parallel to a tangent line of the body of the scope, or exactly how it sits in the stock; I assume this is what you are asking.

Ned,
Yeppers, I was wondering if there was a better way or some voodoo to level the rifle first.
Thanks!

 

[Alex Wheeler]

Its not un common for race ways in actions to not be level to scope rails. Its actually not important any of it is level. What matters is that the rifle is level or canted the same every shot, and for cold bore stuff where you dont get sighters you want the scope's erector system to travel vertically so your not turning elevation into windage, out of square to the gun is just not important.

 

[PatMiles]

What matters is that the rifle is level or canted the same every shot, and for cold bore stuff where you dont get sighters you want the scope's erector system to travel vertically so your not turning elevation into windage, out of square to the gun is just not important.

This is what I am wanting to avoid. Having confidence that the gun itself is level and then the scope is leveled with the gun, thus the erector system is vertical.
Old, blind geezers, such as me, need every bit of help we can get.

 

[Billy 30-06]

The simplest way is to put the rifle in a vice with the rail leveled. Then use a plumb bob to get your reticule straight. I wouldn't trust a rail mounted level.
Billy

 

[ronemus]

Rather than a plumb line, I put a level on a reference flat on the action and another on a scope cap and rotate the scope to match the levels. The reticle may not be true with respect to the erector mechanism (should be, but not necessarily so), so I use a scope cap or knob - that is nearly certain to be true to the erector.

 

[BoydAllen]

The reason that I mentioned doing a tall target test is that the tracking of the intersection of the cross hair may not be aligned with the vertical cross hair. This test will reveal any discrepancy. For work at varying distances, it is best if the CL of the scope is directly above the CL of the bore, both on the same vertical line. The tool that I have, and included a link to is designed to produce that alignment. You can use it to position the rifle before rolling the scope to plumb the cross hair, before shooting a test target.

 

[Hydenseek]

The reason that I mentioned doing a tall target test is that the tracking of the intersection of the cross hair may not be aligned with the vertical cross hair. This test will reveal any discrepancy. For work at varying distances, it is best if the CL of the scope is directly above the CL of the bore, both on the same vertical line. The tool that I have, and included a link to is designed to produce that alignment. You can use it to position the rifle before rolling the scope to plumb the cross hair, before shooting a test target.

If you can align the CL of bore and CL of scope I don’t see a reason not to.

 

[_Raining]

I wouldn't rely on any flat spots on the rifle to tell me it is level. I use a plumb line to make sure the scope bubble level is perfect with the vertical crosshair but I would need to do a tall target test to level the vertical crosshair with the center of the bore.

 

[PatMiles]

Gents,
All good information which I am trying to wrap my head around.
Thanks!

 

[M16_4_REAL]

Most modern firearms are machined on a CNC to very close tolerances, especially custom actions. Close enough that I don’t worry about leveling the action first. I use this machined scope leveler to mechanically level the scope to the base. Has proved so accurate I don’t bother with anything else.

 

[Nature Boy]

What matters is that the rifle is level or canted the same every shot,

This is what I thought. Thanks for the validation Alex

 

[Drop Port]

The simplest way is to put the rifle in a vice with the rail leveled. Then use a plumb bob to get your reticule straight. I wouldn't trust a rail mounted level.
Billy

I wouldn't always trust the reticle to be straight either the scope tracks off the erector not the reticle.

 

[chkunz]

I would probably set it up using the base and then do a tall target test. Or if you can find one, or have a friend who has one (as I do) this will get the job done.
https://www.brownells.com/gunsmith-...ers/vertical-reticle-instrument-prod6097.aspx
It puts the CL of the scope over the CL of the barrel. You can then roll the scope so that the vertical cross hair is parallel with a plumb line.

Boyd, I took a look at the link and could not figure out how this thing works, can you explain a little more please?Clyde

 

[Billy 30-06]

I wouldn't always trust the reticle to be straight either the scope tracks off the erector not the reticle.

If I found the reticule to be crooked I would send it back. With the reticule plumb you should be able to turn the elevation up and down with out the reticule moving left or right.
Billy