Scope Bedding/Mounting

[timeout]

At the risk of exposing how green I really am, I have some questions on scope mounting. I have Tony Boyer's book on rifle accuracy and have read and reread it. I have spent a lot of money foolishly in the past buying equipment not needed, or inadequate to do the job. After reading the book there is so much more to buy, and being retired, I can't afford to waste money. Having never used a bore sighter, what company makes one that has the adjustable verticle grid which will allow me to bed the scope so the reticle is on center @ 100 yards? What is your feeling regarding the advantage gained by having the scope perfectly centered? I realize that in BR, one needs every advantage possible, just wondering where you would rate this process in importance to a shooter? Another question: I have a Tipton Best Gun Vise and also have a "Plumb Bob" line attached to my basement wall for aligning the scope crosshairs correctly. One problem that I encounter at the begining of the process, is making sure the rifle is perfectly level. I have tried different methods, mostly involving a torpedo level. The problem I have is where to put the level. I find that scope mount bases and lower half of scope rings are not always machined to give me the same reading from one to the other. That then begs the questions for me, which is right, or likely, are they both off? I see anti cant bubbles that mount on Weaver style mounts and believe that is great for those. What about other types, including the Ruger factory machined mounting areas? Is there a kit made that works on all rifles/mounting systems? Thanks for your insight.

I apologize if this is posted in the wrong place. Guess I was thinking 6 ppc since I am mainly working on a couple of them currently.

 

[Preacher]

I found the best way to level the rifle is to place a piece of flat steel in the bolt raceway and level off of that, and then use the plumb bob to align the scope...

 

[jerrschmitt]

All of those initial adjustments are approximate. There is no way to set a scope perfect from the bench.

Level the rifle as best you can. Plumb the cross hairs with your plumb bob line. Bore sight the rifle to get on paper, then shoot and adjust.

Once you have it shooting where you want, get a 40 inch tall piece of cardboard and place a target at the bottom. Shoot a three round group at that target from 100 yards. Raise the elevation adjustment 30 minutes and hold on the same target to fire three more rounds. Take your plumb bob and insure that the three top holes are directly above the bottom three holes. They probably wont be.

Make a plumb line from the bottom group to the top of the cardboard then measure the distance right or left to the top holes from the plumb line. Make a mark on the cardboard on the opposite side of the plumb line from the top group. Draw a heavy line from that mark to the bottom group and Rotate your scope in the mount until they are aligned.

At this time you can also measure the distance from the bottom holes to the top holes to insure that the elevation adjustments are accurate.

 

[timeout]

Thanks for the help guys, I greatly appreciate it. I did not describe very well about my boresighter question. Tony sights his rifle in at 100 yards on a target first. Then he installs a boresighter in the barrel and aligns the boresighter with the vertical crosshair of the scope. Next he counts the number of vertical and horizontal grid lines off from the center of the grid. Then he finds exact center for the scope turret adjustments by turning them fully, counting the clicks, and setting to the mid point. After doing this, he removes the top rings and adjusts (shims) the scope until it is set to the original spot on the boresighter grid. The final step is to "bed" the scope into that position with an epoxy such as JB Weld. What Tony is doing is having the scope turrets exactly centered for adjustment when the rifle is sighted in for 100 yards. My questions about this process are 1. What brand/model of boresighter would be adequate to accomplish this procedure? 2. Has anyone ever done this, and in your opinion is the end result worth the work?

 

[jcampbellsmith]

http://www.burrisoptics.com/sigrings.html are what you need.

1 Adjust the vertical and horizontal turrets on your scope until you are in the middle of each range.
2a Mount the scope using no offsets and shoot it and zero it.
2b Borrow one of these:

http://willsfishingandfirearms.co.nz/shop3/firearm-parts-accessories/bore-sighters/nikko-stirling-boresighter-scope-aligner

3 Using the grid on the scope aligner note the coordinates of your zero.
4 Dial the scope back to the clicks you established in step 1.
5 Use the inserts to shim the scope back as near as possible to the point established in step 3.
6 Fine tune the reticle using the vertical and horizontal knobs to get back to the actual zero in step 3.
7 Go shoot it again and fine tune the zero.

Take notes as you go along and keep in mind throughout this process that the scope and rifle needs to be levelled using:

http://www.midwayusa.com/product/529349/wheeler-engineering-level-level-level-scope-crosshair-leveling-tool

or another approach that gives the same results.

This is can be a frustrating job. I spent 5 months and several hundred pounds trying to mount a scope. Take your time, be patient and don't take short cuts.

Good luck. JCS