Rifle Scopes Scope Leveling/Feeler v. Level with Plumb/Results

[997/2man]

Here we go again. New scope (USO SN-3s), new rings, mounted scope using two
feeler gauges. Was very careful, turret assembly very large, easy to get to from diff. angles, nothing better to do, torqued to specs. Looked good, reticle was at top of rings, middle of rail.

Now here is the interesting part:

Put One Hole Groups leveling device on scope WITHOUT looking at bubble level.
Looking through the scope, aligned the vert. posts with a plumb line 40 ft. away.
Bubble was out by 1/2! Yes, half a bubble off. The diff between the plumb line and the vert posts on reticle was less than 1/2 the width of the post, which tells me that the bubble level/plumb line can be very accurate in determining true up/down. Duh, 997/2man, we knew that. Yes, but I didn't think that being off by less than 1/2 the width of the reticle (2 minutes, IIRC) would displace the bubble so much, in this case just about 1/2 a bubble.

Now you are saying "997 is full of shit". Not so fast, try it yourself. I wanted the feeler gauges to be more accurate, but it looks like the level/plumb is the way to go for me. To test it, tomorrow at the range, bringing my 4' level, drawing a true vertical line on the target, will run my groups 1-3 feet up, see what happens. If the rounds stay on the line, I think that I'm gtg.

I didn't think that being just a little off (less than the width of the reticle post) would put the bubble so far off, like obviously waaay off.

997/2man

 

[oneshotkyle]

Re: Scope Leveling/Feeler v. Level with Plumb/Results

what rifle, base and rings are you using? i've been happy with the feeler gauge method lately but would like to here your results at the range.

 

[Lowlight]

Re: Scope Leveling/Feeler v. Level with Plumb/Results

Bubble levels are absolutely off, especially if they are rail mounted versions... which is why most people prefer a level you can actually level to vertical and not "take their word for it" by simply slapping it on a rail and calling it good...

 

[997/2man]

Re: Scope Leveling/Feeler v. Level with Plumb/Results

The rifle is a JP Enterprises LRP-07. The scope is a USO SN-3s, the rings are USO. Feeler gauges are Snap-on (I don't know who made them). I'm using rings, instead of a mount for this rifle/scope combo, want it low, not running buis.

I'm using a fine string, very bright neon color, no problem seeing it well.

Mr Haaken said it: scopes can be off 1-3 degrees from vertical. The width of the JNG reticle at widest part is 2(?) minutes, checked USO site, not up yet, was going to check reticle width in options. It was easy to get very fine changes in scope position, plumb very thin in comparison to wide reticle. I'll see tomorrow. Good weather, I've got about 120 rounds, will go to 600 yards if time permits. The scope has EREK, large elevation changes are quick/easy.

Will post pics of groups.
Thanks, 997man

 

[Grump]

Re: Scope Leveling/Feeler v. Level with Plumb/Results

Waiting with bated breath on the results here.

I was a bit surprised at how much rotation I could get with feeler guages only a bit loose. I now favor going tight, then reducing the stack as the rings get tighter.

I also know that the feeler guage only guarantees a reticle perpendicular to the BASE itself only if the reticle is correct inside the scope.

 

[Tribe]

Re: Scope Leveling/Feeler v. Level with Plumb/Results

Get a level that mounts to the tube of your scope.

Get behind the gun, level the reticle to a plumb line, torque the rings (patiently)... checking frequently to verify that the reticle isn't turning on you.

Get back behind gun.... with reticle on plumb line, position scope-tube-mounted-level, so that bubble is where you want it... tighten (patiently).

Shoot.

 

[lightwind]

Re: Scope Leveling/Feeler v. Level with Plumb/Results

I'm confused. Above was stated: "Mr Haaken said it: scopes can be off 1-3 degrees from vertical."

Does that mean you can expect the top turret to be tilted from the reticle by as much as 3 degrees? Does that also mean that when you turn the turret it can be pushing the erector off-center? I actually have a scope that appears to have a difference between vertical of the elevation turret and the reticle. I initially thought it was they mounting but I went back and tried it again and got the same tilt. Is this a common problem? I figured they should be much less than a degree and probably just a few minutes. Anyone got experience with this issue?

 

[azimutha]

Re: Scope Leveling/Feeler v. Level with Plumb/Results

I stack just enough gauges so that the scope will pivot just slightly in the rings (with the gauges as the fulcrum). Then tighten down one ring, slide the gauges out and do the second ring.

 

[Blackbrush]

Re: Scope Leveling/Feeler v. Level with Plumb/Results

Total neophyte here.......

How do you make sure the gun itself is vertical before you level the scope? Plumb line centered through bore and empty rings?

This is something I should have learned a LONG time ago.

Thanks

 

[Petey]

Re: Scope Leveling/Feeler v. Level with Plumb/Results

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: gabbott</div><div class="ubbcode-body">Total neophyte here.......

How do you make sure the gun itself is vertical before you level the scope? Plumb line centered through bore and empty rings?

This is something I should have learned a LONG time ago.

Thanks </div></div>

Well, as overkill as it probably is, here's what I do. Keep in mind, this is with a Horus reticle optic so my main objective is to keep the reticle plumb for proper hold-offs; I couldn't care less if the scope body itself is properly square/parallel/etc with the rifle itself. Rarely is the reticle perfectly square with the bottom scope body surface.

First, I clamp a parallel bar on the top surface of the Picatinny rail and then slap my Starrett 98-6 level on top of the parallel bar. This allows me to get the rifle itself totally level. The next step, while keeping the rifle level, is to rotate the optic in the rings until the reticle is perfectly parallel to a plumb line I have outside the window about 50 yards away. Tighten rings and it's all set.

Where I mount scopes where I'll be dialing instead of holding, then I use feeler gauges, parallel bars, etc to make sure the bottom of the scope body is parallel to the rifle base so that the turrets track true to the rifle itself.

 

[Killer Spade 13]

Re: Scope Leveling/Feeler v. Level with Plumb/Results

I use the Starrett #99 Master Precision level . . . talkin' bout OVERKILL !!!

Petey, that's the most accurate setup I've seen so far. I'll have to post mine.

 

[sobrbiker883]

Re: Scope Leveling/Feeler v. Level with Plumb/Results

I use feeler gauges (tight), and check my built in USO levels against a weighted piece of chain hanging at 500 yards.

All my SN3's are done this way and have been dead nuts on (reticle matches plumb with bubble and with the scope's tracking).

I make sure I am under the erector housing and clear of the access port at the bottom of it when using the feeler gauges.

 

[ARsR4ME]

Re: Scope Leveling/Feeler v. Level with Plumb/Results

I tried the feeler gauge and never could get it to work well. I use three levels that I got out of a torpedo level, they're all the same size that way. While most try and level everything, I found it better to use one side of the line on the level. For instance, lean the action to where the level bubble just touchs the Left line....then rotate the scope to where it's level bubble is just touching the Left line. This way your not trying to find the center, it seems to be better. BTW the little level vials that you get when you break the level open, be sure and check them by stacking them on top of each other and make sure they are all reading the same. My 2¢