Volume: 16 | Back to issueSubscribe Now
column By: Lee J. Hoots | May, 18
While recently mounting a Leupold VX-3i 4.5-14x 40mm CDS scope with Duplex reticle to a Model 700 .223 Remington varmint rig in a Stocky’s Stocks M50 AccuBlock stock, it occurred to me that very little space in hunting magazines has recently been devoted to mounting scopes on sporting rifles. I suppose the installation process, which is simple enough on most modern rifles, is taken for granted these days. If that’s true, perhaps a new generation of up-and-coming hunters are also being overlooked.
At nearly every public shooting range, a few fellows volunteer their time, dedicating several days each summer to help both new and experienced hunters get their new riflescopes properly fitted and zeroed right up into September. It’s also not inconceivable that many rifles and scopes are purchased within a few days (sometimes hours) before opening day. People are busy. As such, properly mounting a scope seems a “fitting” subject considering many hunters will be picking up new-to-them rifles during the months following this issue’s publication.
There are far too many variables among rifles and scope mounts to discuss them all here, especially when such variables may or may not prove important in the long run. Basic scope mounting has not changed, however, and mounts and rings, in general, have become more accommodating. The goal here is to offer the new rifleman hunter enough information to increase confidence when setting up a new rig so the scope will perform well enough that its owner can enjoy his or her time afield.
With that thought in mind, however, no article on scope mounting basics should ignore another important and often neglected point: If there is an old and trusted rifle available – say a .270 or .308 Winchester, .30-06 or a 7mm Mauser or 7mm Remington Magnum, or any other number of options – and you’ve just pulled a difficult-to-draw permit (maybe even an elk tag) – a hunter does not necessarily need another rifle or scope. If on the other hand there remains a simple craving for something new, then by all means, indulge – provided the reasoning is not overshadowed by a silly notion that a new rifle is the only route to success. Of course, a broken scope should be replaced.
If significantly pressed for time, the best and obvious advice is to take the rifle, scope and mounts to a trusted gunsmith; especially one who will let the customer watch and learn, and more importantly, set up the scope’s eye relief for its owner. Keep in mind, however, that many of these fellows are awfully busy repairing rifles and mounting scopes for other clients prior to hunting season, and sometimes gearing up for their own hunts. Fortunately, scopes are easily mounted with basic and inexpensive tools (some of which come with a set of mounts) and a bit of thought and effort.
Assuming correct mounts have been purchased, the first step is cleaning all traces of packing oil or grime from all parts to be assembled, including the screws. The same is true for the threaded holes in the rifle’s receiver. This is easily accomplished with a bit of simple alcohol or acetone on a rag and/or small swab as the case may warrant. The use of a more aggressive degreaser is usually unnecessary. Do not use a rust remover because it will strip the bluing from the mounts. All such fluids should be kept from contacting wood or composite stocks as the surface finish may be damaged. If a swab leaves cotton strands in the receiver screw holes, pick them out with a toothpick or use a compressor to blow them out. Foam-tipped Swab-Its (swab-it.com) are an excellent alternative to cotton swabs.
Attach the cleaned and dry mounting base/bases to the receiver with accompanying screws as indicated by the manufacturer. Do not apply a thread-locking agent to the screws, as doing so is unnecessary and is certain to cause a headache should the bases need to be removed later. Some scope mounting assemblies come with a drop of polymer on the base screws to secure them in place yet allow their removal. There is no need to wipe this off.
Mount the rings as directed by the manufacturer. Place the scope in the rings and start the ring screws just enough so the scope can be positioned and adjusted for eye relief, or the distance from the rear ocular lens housing to the eye when the rifle is shouldered. If using a variable-power scope – and almost all new scopes are of variable magnification – eye relief positioning should be made with the scope dialed up to its maximum magnification. This is best done by shouldering the rifle and moving the scope forward or rearward to a point where the entire reticle can be seen without having to move your head back and forth along the comb of the stock. When preferred positioning is defined, lightly snug the screws on the top mounting ring so the scope is not likely to slide forward or rearward without manually being moved.
At this point the reticle needs to be made level, which can be done using a rifle rest or a cardboard box large enough to support the rifle and a couple of small, inexpensive spirit levels, preferably those with magnetic strips to hold them in place on steel bases or elevation adjustment dials. Cut “V” notches in the box so it supports the rifle, then place one spirit level on the flat surface of either the front or rear mounting base and level the rifle. Place a second level on the scope’s top adjustment turret and rotate the scope until both levels are plumb. Snug the ring screws to the manufacturer’s torque rating (usually about 25 inch-pounds) while keeping even tension on both sides of the rings – think tightening alternate lug nuts on a pickup if the rings have more than one screw per side.
Inexpensive screwdriver-type torque wrenches and small spirit levels can be found at most hardware stores, and for an investment of around $100 or less will minimize the likelihood of permanently damaging the scope tube by overtightening the ring screws during the installation process. More than one optics manufacturer has said that when scopes come in for repair or warranty, the majority have been damaged by overtightened scope rings.
Small spirit levels work exceptionally well for leveling scope reticles, even if the level must be placed on the flat cap of the turret housing. There are times when a level will not fit between the mounting base and the scope, so for many years I have used a very simple tool called the Reticle Leveler that retails for about $20 and features a built-in spirit level. Mine is a prebubble version. Both the new and older versions feature horizontal stripes that allow the user to verify a scope’s horizontal “wire” is lined up properly. In fact, many scopes have been lined up with the old Reticle Leveler and later verified with bubble levels that have indicated the reticle was perfectly horizontal.
I’ve been asked now and then which scope rings I prefer, and there is no fair answer other than I have no use for rings/mounts made completely of aluminum, with the important exception of Talley Lightweights, which have proven to be very rugged. As with a scope, hunters pick mounts for personal reasons: long experience, their buddy uses a certain brand, or maybe they just look right on a certain rifle.
Scope rings come in a bewildering array of configurations, from the Weaver-type clamps to twist-in rings and the increasingly popular cross-slot rings for Picatinny-type bases. Along with these are steel mounts such as those made by Talley Manufacturing and Control, which add elegance to a fine sporting rifle. Keep in mind, however, that durability and ease of use can prove more important than looks.
For many years I have had good luck with Leupold STD or Burris’ similar Trumount steel ring-and-base assemblies with a twist-in front ring and double-screw, adjustable rear ring, because the “windage” screws on the rear base provide slight lateral adjustment when rough zeroing a rifle without the need to adjust a scope’s windage turret. These screws, however, are often mistakenly used for very course adjustments during sighting in, resulting in a rifle and scope combination that is far out of alignment. In extreme misalignment situations, the shooter will have to cock his head over the riflestock comb, or away from it – not a good situation for any kind of shooting. The rear ring needs to be centered on the base as a starting point, not spun out too far to one side or the other; and it should not be moved too far from center when rough zeroing the rifle. A simple caliper comes in handy to center the rear ring in the base.
Many shooters today have gravitated to cross-slot rings, so I’ve begun using them more often myself, finding them to be quite durable. While I will not pretend to have used all types and brands of rings, for toughness, Talley fixed rings are among the strongest steel scope mounts around, and Ruger’s proprietary fixed rings are also tough as nails. In fact, most modern scope rings are pretty darn good. All of them are relatively easy to install.