Wednesday, March 4, 2015

Revisiting My Scope Ring Alignment Tools

This product was recently mentioned in John Barsness's newest book, Modern Hunting Optics that was reviewed on this Blog and I felt this was a good time to revisited the subject.

More often than not I am required to develop a tool for my own use and sometimes find others just might benefit from the same tool or fixture. This is the tale of such a tool. Both these 1" and 30 mm alignment tools are made from precision ground steel round stock. Rigidity is the name of the game here.

These 1"and 30 mm alignment tools were originally developed for the specific task of aligning both the front and rear scope rings that I install on the given receiver after the fabrication of these rings. The ID of both the front and rear ring is bored to the specific scope diameter + .001 They also serve to re-align the finished scope mounts whenever they were removed and or re-installed on that receiver.

Since my ring and base are integral I wanted a way tighten the base screws to the action and keep the rings in alignment. These tools allow access to both the front and rear sets of scope base screws. As the screws are tightened down the tool aligns the front and rear mounts in the same plane as the screws are drawn up tight. Even with a precision fit set of rings made to exacting tolerances I wanted a simple way to prevent one ring from possibly leaning to the right and the other to the left or twisting under the torque of the screw driver during the installation. These tools have been used in my shop for many years now and shipped to many clients that have both a set of 1" and a set of 30 mm rings for a singular rifle. Having both the 1" and 30 mm tools allows them to switch out and reinstall either set of rings  simply and accurately when required.

Over the years we also found a number of other scope mounting uses for these tubes that are very practical for the home enthusiast or professional gun smith using both custom and  conventional industry mounts. These tubes like any other bar type tool can be used to rotated the front ring 90 degrees into position and by having the rear ring attached to the tube as well will allow you to snug the rear ring into place with the scope base windage screws. The rigidity of the tube will insure that the rear ring is inline with the front ring and that the scope will not be put under and undue stress laterally.

However this tool and method will not correct any vertical misalignment issues in height between the front and rear ring. It will instantly make obvious the amount of height deferential and allow you to determine if you will want to install a shim under a base to correct the height issue. I recommend always placing the shim under rear base so as to prevent elevation correction in the scope to be compromised.

Once you have installed a set dual dovetail rings and labored over getting both rings in-line with the typical assortment of tools for this job such as using apposing flat or pointed rods placed in each ring to turn the rings into alignment. Then lapped the rings to gain as much contact with the ID of the rings and the scope. The thought of then removing this set up and ruining the fruits of all that labor can cause you certain amount of mental grief. If base arrangement will allow you access to all 4 of the base screw holes. You can remove the lapped rings and bases together and mark the forward edge of each ring and then send the paired rings and bases assembled together to be blued.

This prevents rust from forming over the years in the lapped ID of the ring and yes this does occur even with completely blued rings as seen in the pic below. With lapped but unblued rings this rust occurs at a very rapid rate.

Done in this manner maintains the necessary friction required to hold the rotary dovetail firmly in the base. Every time you rotate ring in and out of a rotary dovetail it degrades the fit on both the male and female contact area of the set. In short the interference fit of both the rings and bases degrades to the point that renders the set up as loose as a goose and keeping the rifles zeroed is like accurately predicting when the Congress and Senate will vote on any issue together.

Here is another example of where this alignment tool also comes into its own. If the set of rings you've installed and invested all this work into allows you access to all the base screws without removing a ring, leave the lapped set of rings assembled and unscrew them from your receiver for future use or to install a higher set of rings for that 56 mm Hubble sized scope you have always wanted. When the time comes to switch the scope back to a 3.5-10x40mm use the alignment tool to reposition both the lapped lower set of front and rear base/ring combination back onto the same rifle. This is simply done by placing each base/ring back on the receiver, drawing up the scope base screws just enough to take any excessive slack out of the screws but still allowing the mount to wiggle around ever so slightly. Place the alignment tool into both bottom ring halves press the tube firmly towards the receiver and snug up each base screw through the tube body and the slots provided.

Some mounts position one or two of the scope base screws actually under a ring, usually the rear ring. This is fairly typical with older style 2 piece Redfield or Leupold windage screw rear mounts or most vertically split mounts system such as the Talley, Warne, etc. In this case you will not benefit from the use of these alignment tools during an installation or re-installation. The tools will work equally well with the Leupold QR and QRW style rings and Weaver or Picatinny style rails and rings as long as the ring placement does to obscure the base screws. Below a set of Talley Aluminum horizontally split rings are being installed using a 1" Alignment tool.

For those that might be interested in acquiring one or both of these tools I keep and quantity of these in stock and can be order directly from the shop by calling 435-755-6842 or from my Web Site at The cost is $112.00 per tool plus the shipping cost. Please note that USPS will always be cheaper.

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