Home Forums Hunting & Shooting Hunting Optics Windage adjustable scope bases

Almost anyone who is knowledgeable about mounting scopes in Leupold dovetail rings will tell you not to use the scope to turn the ring into a base because it could literally bend the scope, causing irreversible damage.

Then, a windage-adjustable rear base is offered.

So, you have your scope in a front dovetail mount and the rear base locks the scope ring in place and large screws move the ring right or left to compensate for manufacturing errors in keeping the the axis of the scope concentric with the bore. This is a way to keep from running out of adjustment on the windage turret and having the erector assembly essentially resting against the right or left side of the scope body internally. This, of course, eliminates the ability to adjust the scope for elevation. If I'm wrong thus far I'm certain I'll be corrected.

Back to the windage adjustable base. Say for example, one needs to have a large windage adjustment using the rear base and rear ring. As you adjust the windage ring the scope is turning the front dovetail ring. How is this any different than using your scope to seat the dovetail ring in the first place?

As you are turning the screws to adjust windage on the rear ring, I guarantee your front ring is not turning(and if you adjust it enough it will bend/torque your scope tube).

All you need to do is take a 1" piece of wooden dowel rod and use it to turn your front dovetail ring in the base to see what using your scope as a pry bar will do to it.

Redfield/Leupold type windage adjustable scope mounts are a fairly antiquated design and were originally used for mounting scopes that had little internal adjustment. Personally, I stay clear of such mounts; there are better options out there(use dual dovetail mounts and lap your rings or use Burris Signature rings with the plastic offset inserts if you need to do much windage adjustment to get your scope on target).

So, to answer your question: Yes, using windage adjustables(like the Redfield/Leupold type) to make large windage adjustments is essentially bending/torquing your scope tube and it will show by way of deep gouges in the side of your scope tube.

Leftybolt

I disagree. If not, then you are not changing the windage adjustment. I will agree that it could be bad for the scope. I also think that a few 1/1000's " is a lot less stress than turning a scope 90degrees as you mount it.

I also agree that it is far better to avoid any mount using dovetails or windage adjustments like the plague unless they are truly needed. Even then, If I had a rifle so screwed up that I needed windage adjustable mounts to get my scope zeroed I'd probably trade rifles before I'd put up with that type of mount.

though i'm not a great fan of the standard ring/base system for general hunting, it has served many a hunter and shooter very well over the years.

despite that fact, most anyone would prefer to drive a car rather than pilot a covered wagon. we have some really good ring and base systems these days--especially for hunting where rigs are exposed to some hard knocks during use.

these days, standard rings/bases are at their "best" on rigs with alignment issues, and a second place for them is on varmint rigs used from static shooting locations, such as prairie dog shooting, etc. of course in the spirit of "period correctness", they often belong on classic and vintage rigs too.

regarding the use of this ring/base system--preferably, all alignment and adjustment should all be done prior to the scope installation.

the only time you should ever consider using the rear base windage screws to move the scope within the rings is only after the front ring dovetail has been carefully lapped during the installation of the ring.

That dovetail ring and base is a one-use piece of gear. You carefully turn that dovetail ring into place and it is then as solid/tight as it's ever going to be. Any further use of it, like taking the ring out to move the whole system to another rifle leaves you with a ring and base that have metal displaced where they fit together. The second time you turn the dovetail ring into the base the fit is not as tight and even more metal is displaced. Eventually the result would be a loose, sloppy fit of the dovetail ring in its base. Lapping the ring into contact with the base is prematurely weakening the dovetail ring/base fit. If a proven scope in that system shoots a pattern rather than a group the first place I would look would be the front ring/base lock-up.

you should note that i mention that it is best to make all alignment adjustments prior to the scope being installed--this is best done by means of the utilization of the proper tools, and a reasonable dose of experience and skill.

in those cases where a chap decides to make adjustments with the scope in place (something that i don't advocate), the front dovetail must be carefully lapped into the base first, so that the front ring that is holding the scope captive, "is free to rotate" the necessary amount in order to achieve appropriate windage alignment. these days with the qc issues on these systems, this is harder to achieve--leave it to those old timers and the hard case guys...

i hear what you're saying about "one use", that is my personal preference--and my way of doing it as well, but numerous old time professional gunsmiths often lapped these in so that they could obtain necessary alignment with the scope in place--without bending the scope, or creating "witness marks" on the scope tube. I have one rig that was done this way by one of these chaps back in the 1960's--it works perfectly, and there are zero problems caused by this type of lapped in front dovetail.

as i mention, these days (about the past 4-5 years or so) the fit on these dovetails can be so poor in some production runs, that one gunsmith friend of mine told me that just turning the ring in the necessary 90 arc has resulted in the dovetail itself snapping off of the ring stud--rendering the ring (and sometimes the base), totally useless. he had a whole group of these that had to go back to the manufacturer. last fall i attempted to install a set of dd's on a rig, and the front ring/base fit was so poor, that in the process the base was damaged, and the dovetail was shot. the set went back to the store, and they sent them back to the manufacturer. in my opinion and experience, the qc on these systems has taken a significant nosedive in recent years...

I agree with the aforementioned. I`ve used the Leupold and Redfield bases and agree that one should never rotate the front set using the scope as a lever. To avoid torqueing the scope when making the windage adjustments if the rings allow it I don`t install the top halves. I set the scope in the bottom halves and tape/or securely wrap it in place. Now, boresighting can be accomplished and if the rear base is adjusted you can adjust the front base using a brass drift and light taps.Once the windage is set I then install the top halves minus the scope use the alignment rods to check that they are centered and lap if necessary. Modern scopes with constantly centered reticles seldom need these steps.If you play with some of the old ones as I do these mounts sure come in handy.
Joe

All valid theoretical points. Nevertheless, shooters have successfully used W/A mounts for many years. I've never had any problems, and yes, I (occasionally) use the scope as a lever to rotate the front ring (gasp!). Most of my rifles shoot sub-MOA consistently, and the scopes (generally Leupolds) haven't failed.

Cheap ring lapping kit from Brownells = nearly priceless for any mounting system. Since I started doing it I have not had a mark on any scope- which I take to mean I have very good alignment in my rings. I normally use dual dovetail and rarely the windage. Always Leupold bases/rings because they have yet to fail me. Doesn't mean they are perfect. Just continually work for me.