Mounting systems can be purchased individually or in combos, such as this RedHead Z2 Ring and Base Scope Mount Combo.
Most hunters and shooters today realize the benefit of quality optics atop their firearms and take care in choosing just the right scope. But even the finest glass that money can buy is still only as good as the mounting system used to secure it to the firearm. Mounting systems consist of some type of base that attaches to the firearm, and usually two rings that hold the scope to the base. Choosing the right bases and rings is critical, but the choices available can be confusing. Here's what you need to know.
The first choice you need to make is the bases. Mounting bases are available in essentially three distinct styles: Redfield/Leupold, Weaver and quick-detachable. Let's look at each:
Standard Redfield-style bases, named after the original patent holder, secure the rear ring by way of two horizontal windage adjustment screws, while the forward part of the base accepts a turn-in or dovetail-style ring, locking it solidly into position. This is a very secure and popular system, and has the advantage of providing significant windage adjustment capability before having to utilize the internal windage settings of the scope. A variation of this system, the dual-dovetail, with turn-in rings used both front and back, has also become very popular. They are seen as being perhaps a bit more secure than the standard set-up, and are ideally suited for large caliber or heavy-recoiling rifles.
Weaver-style bases, also named after the original patent holder, use flat plates with slots cut into them to secure the rings by way of a horizontal locking screw/claw combination on each side. This is also an extremely popular system, with versions to fit just about every factory made rifle on the market today, and tends to cost a bit less than the Redfield-style system. The Picatinny is a variation of this system with slots cut along the entire length of a single rail, allowing for maximum flexibility in mounting a variety of sighting devices and other tactical accessories. The Picatinny rail is popular among "black rifle" or AR-15 enthusiasts.
The final main mounting option available is the quick-detachable system. This set-up utilizes two levers to lock the rings into the bases. The beauty of this system is that, as the name suggests, the scope can be quickly and easily removed to allow the use of the rifle's iron sights, and then re-attached without losing point-of-impact or "zero". This is ideal for hunting dangerous game in settings where both longer-range and close-quarters/heavy cover follow-up shooting may be required on short notice.
All of these bases are available in either one- or two-piece models. This is usually a matter of preference, although in some cases fit prevails and only one or the other will work on a given firearm. Where every ounce matters, such as on a lightweight mountain rifle, two-piece models are generally a bit lighter, and are arguably a bit stronger, given that a total of four screws are used to secure two-piece bases, while one-piece models often have only three.
Though rings are largely dictated on the chosen base, there are choices to be made in selecting the perfect rings.
Regardless of what style of bases you choose, they have to fit your firearm. All manufacturers of mounting bases make their products to fit certain makes, models and action lengths of firearms, and their catalogs or websites will tell you which product is suited for your specific gun. The good news is that just about regardless of the firearm you have, someone makes a mounting system that will fit it.
Obviously your choice of rings will largely be dictated by the bases you have chosen, as they must match the specific style of base used. However, there are still choices to be made in selecting the perfect rings.
The fundamental determination that must be made is the diameter of the tube of the scope being mounted. Most standard scopes are either one-inch or 30 mm diameter, and most styles of rings are available in both of these sizes. It is difficult to see the difference visually, so make sure you carefully check the websites or the specifications on both the scope box and the rings packaging.
Once you have selected the proper size of rings, you then have to determine the correct height of rings. Most rings are available in low, medium or high. It is always best to mount a scope as low to the bore as possible, but how low depends on the scope being mounted.
Scopes with larger diameter objective lenses are increasing in popularity, and these large objective lenses require at least medium and sometimes high rings to ensure that the front bell of the scope is not touching the gun at any point.
In addition, when mounting on a bolt-action rifle, there must be sufficient clearance to ensure that the bolt handle does not strike the rear scope body when the action is being worked. The website or catalog of the rings manufacturer will often indicate the height of rings required for various firearms with different sizes of scope objective lenses.
Scopes need to be mounted with proper eye relief, which is the distance between the shooter's eye and the rear of the scope. In doing so, some particularly long or short scopes may not fit properly in standard rings, due to interference from the adjustment turrets in the center of the scope, or the front or rear scope bells. For this reason, extension rings are available to give more clearance room for proper mounting.
An integral base and rings combination has also recently become available. This clever design is machined from a solid block to create a one-piece base and rings system, resulting in no moving parts between the firearm and the scope.
One-piece scope mounts feature no moving parts, eliminating possible misalignment.
Rings and bases are generally made of either steel or aluminum. Steel has long been the standard, especially for large caliber or heavy-recoiling firearms, as it is the strongest construction. Aluminum is lighter, and tends to cost less, and the use of various alloys can make certain set-ups nearly as strong as steel.
Many models of bases and rings can now be had in various finishes to match the finish of the firearm and/or scope, including gloss, matte black, stainless and even camouflage. Having said that, some very attractive contrasting combinations can be achieved, such as a stainless scope with matte black rings and bases.
There are also a couple of special purpose mounts that are worth mentioning, namely see-through and shotgun.
See-through rings are basically high, Weaver-style rings that allow the shooter to see and use the gun's iron sights underneath the scope. This set-up can be handy when hunting in heavy-cover where close, fast shooting with open sights may be necessary, while still allowing the use of the scope for longer shots.
Shotguns that are designed for use with slugs or buckshot for hunting deer are typically set up from the factory for mounting of a scope. However, it is also possible to mount a scope on your favorite upland scattergun by way of a saddle mount, which essentially adds a Picatinny rail to a smoothbore with no gunsmithing required.
Experts advise to spend as much as you can afford when purchasing a new scope, and that's good advice that you won't regret. But selecting the right mounting system is just as important, as this will form the critical link between your expensive new scope and your firearm, and allow you to enjoy maximum performance when all of these components function together seamlessly.