Trouble finding level to mount scope

[H25]

I cannot find a good place to call level on the receiver of the weapon to start my scope mounting.

Rifle is in a solid jig and does not move.

Level the rifle at the most forward lug of the receiver and lock it in. In theory this should be level to the bore, correct? Wrong. Using both a verified level and an angle finder as I move to the next lug in the rail it becomes off by 1 degree and continues to grow as I get closer to the charging handle. Meaning about every 1 inch the "level" changes.

I have three 15-22s and I have confirmed this is the case on all of them. Looks like a quality control issue during manufacturing.
All these weapons are new never fired.

The question is: What are you doing to fix the problem? If the the base that the scope mount sits on is not level to the bore then how will the scope ever be plum of the axis?

How are you determining the bore is level and plum before mounting scope?

Thank you

 

[bamashooter]

Unless you get into shimming and the like, the mount is going to be only as consistently parallel with the rail as the parts allow. The optic doesn't really care as long as there's enough az/el adjustment to satisfy your goal.

I just lock the AR in a vise and use a carpenter's level on the rail. And I only use the level to satisfy my ocd and not for anything pertaining to the accuracy of the optic / firearm. Mount it all. Use a thin string at a few yards with a weight hanging from a curtain rod (like a plumb bob) in the house. Align the vertical hair of crosshairs to the string. Carefully cinch it down, check the alignment, and call it good. It's all relative. Go zero and high-five myself for living the simple life.

 

[Destructo6]

Well, the clamping surface of a picatinny 1913 rail is the two surfaces adjacent to the side angles, not the top surface. So, while a slight defect there may be annoying, it may also not be particularly important, assuming you are using a 1913 compatible mount, not a NATO mount.

How are you determining the bore is level and plum before mounting scope?

Using a 2-4MOA red dot and bulk ammo, I'm not concerned.

What do you intend to do with your MP15-22s that requires this sort of accuracy?

 

[gwpercle]

You are overthinking this way too much.
Mount a scope , follow manufacturers instructions , tighten everything up and go shoot it.
The most important thing for me is getting the cross hairs vertical and horizontal (not canted) but you would cringe at my untechnical way of doing this.
I have always preferred Weaver mounts and rings .
Mount and shoot !
Gary

 

[s&wchad]

Very few rifles are square and true. It's common for rails or mounting holes to be slightly off center. Barrels aren't always straight and concentric to the receiver and even stocks can be crooked. To compound matters, a lot of scopes (even relatively expensive ones) have crosshairs misaligned with the turrets. You can drive yourself crazy trying to square things that aren't plumb!

One of my pet peeves is crooked scopes. I see a lot of them that are way off, because the previous owner naturally cants the gun and just mounts the scope so the crosshairs look level to him. It doesn't really matter if you always shoot at the same distance. The misalignment is easy to see if you look into the scope from about a foot back. You'll only get a partial field of view through the scope, but you will see the crosshairs and can compare them to the rifle. Just mount the scope so it looks good and call it close enough. This method is fine, unless you do a lot of precision shooting at various distances.

Long range varmint/target shooters need the scope directly over the bore and square. The best way to verify this is at the range. Use a grid type target and make sure it's mounted square (take a level). Shoot off a sold rest and zero the rifle. Then make about a 10" elevation adjustment (either with the top turret or with the mil-dot/graduation marks) and shoot a group. If the group is directly over the center of the bullseye, you're good to go. If it's off to one side, slightly rotate the scope the direction of the error and start over.

 

[MichiganScott]

Level the rifle at the most forward lug of the receiver and lock it in. In theory this should be level to the bore, correct? Wrong. Using both a verified level and an angle finder as I move to the next lug in the rail it becomes off by 1 degree and continues to grow as I get closer to the charging handle. Meaning about every 1 inch the "level" changes.

I have three 15-22s and I have confirmed this is the case on all of them. Looks like a quality control issue during manufacturing.
All these weapons are new never fired.

I would suggest that all three rifles being off simply mean that they are "within tolerances" and not a QC issue. They probably came from the same mold.

 

[Blackstuff]

Its a .22 plinker you'll be using out to 200m max, not a 1500m precision rifle for serious competition. Slap the scope on, eyeball it, zero it and just enjoy!

 

[H25]

You guys make me

Yes, I do realize I am over thinking it. Unfortunately this is the nature of who I am. I except nothing less than perfection in what I do, on .. everything. : Wife loves that by the way

I am an experienced shooter, but have never required or shot a scope. Stupid me thought, you know I think I want to try a scope.

So it is my understanding that the idea of mount and "leveling" a scope is to make it level and plumb to the centerline of the bore. Thus making the point of intersect true and accurate with any adjustments you may make to the reticle.

If this is in fact the case, then if they were to be paired at only 1 degree apart this would effect the point of impact.

Is it a 22? Yes. Will I be shooting long range? No. Will several other variables over power such inaccuracies such as wind, gun cant, shoulder weld, breath control, shivers, etc. Yes.

But, as I learned at a very young age. If its worth doing, then its worth doing right. And "good enough" does not exist in my life. : You should see my house ... its ridiculous

So the question is. What point or where are you setting the level to assure the weapon is level prior to installing scope mount?

 

[H25]

Well, the clamping surface of a picatinny 1913 rail is the two surfaces adjacent to the side angles, not the top surface. So, while a slight defect there may be annoying, it may also not be particularly important, assuming you are using a 1913 compatible mount, not a NATO mount.

Using a 2-4MOA red dot and bulk ammo, I'm not concerned.

What do you intend to do with your MP15-22s that requires this sort of accuracy?

Clamping is the sides, agreed. But the mount still rests on the top. So that would make the top for position and level. The sides for retention. Correct?

Mount? It is my understanding that the mount is for 1913
Warne X-Skel Mount

Intentions? FUN Of which BTW this is not.
Ok, really. Plinking. I shoot steel plates 4" and 12" Have one of my 15-22 set up with red dot for CQB, so lets call it 25 feet to 50 yards. This unit I figured would be 50 yrds to 150. Really I can get there with the red dot, but again never shot a scope, wanted to try a scope.

 

[Blackstuff]

You guys make me
So the question is. What point or where are you setting the level to assure the weapon is level prior to installing scope mount?

And the answer is; no one else is because its a waste of time and effort. Other than the possible problems which would result in greater inaccuracies than a 1 degree error in scope mount you listed, there is also the inherent inaccuracy of direct blowback actions and the way the barrel is mounted in this particular gun. You won't notice the any scope error above these, especially when shooting at 50yards or less.

 

[MichiganScott]

An additional question occurs; how will you guarantee that the mount itself will not be off by 1 degree, or more, simply due to tolerances in the system?

 

[Muss Muggins]

Just get it close. Those two knobs on the top and side of the scope are for making the scope point to where the rifle shoots . . .

 

[bamashooter]

Though this doesn't satisfy your quest for perfection, it's not doable and doesn't matter. Factor in the imperfect parallelism of the receiver to barrel and the trajectory of the bullet. The trajectory alone defeats the purpose of striving for the impossible goal of laser-like perfection. The az/el adjustments will accomplish what you need. Once that's accomplished, consistency is the name of the game. Now lets talk about environmental influences.