Sights

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Iron Sights

Telescopic Sights

Scope Mounting

Shotgun Sights

With the exception of shotguns (which we will deal with separately) all target rifles and pistols have some system for allowing the shooter to aim the fall of the bullet onto the target. These systems are sights.

 

Possibly the oldest, simplest, and in some ways the crudest sighting system is the post and notch; this system is widely used on hunting and sporting firearms and is mandatory on most types of target pistol.

In its basic form it consists of a blade or post foresight, fitted on the top surface of the gun barrel, near the muzzle. Somewhere near the breach, on top of the barrel or receiver is fitted the blade rear sight. The blade usually has a square or 'U' shaped notch cut in it. The blade can usually be moved up and down, or side to side in small increments, either by 'drifting' it in a dovetail fitting, or by using some sort of adjusting screws.

In practice, the shooter aligns the front blade in the rear notch and places the target so that it appears to sit on the foresight. If the sights are correctly adjusted for the distance to the target and for any left or right windage adjustments, then the shooter should hit the target.

This is fine on a sporting arm, or a military rifle, but such sights are simply too crude for target shooting using very small targets. In addition, they are hard work if your eyesight is not perfect.

Small-bore match and full-bore target rifles, together with match air rifles use a variation on the theme - they are fitted with a 'tunnel' foresight, again at the muzzle, and a 'dioptre' or peep-hole rear sight, usually at the rear end of the receiver. The foresight consists of a short piece of tube which forms the foresight tunnel. The axis of the tunnel aligns with the axis of the bore. Into the tunnel fits the foresight 'element' which is usually in the form of a metal ring, or transparent plastic disc with a hole drilled through its centre.

The rear sight is essentially a peep-hole through which the shooter looks with his aiming eye. The 'sight picture' he sees is of the circular target centred in the hole of the foresight element, with the foresight tunnel centred in the peep-hole.

In reality, these sighting systems are extremely complex. The foresight element can be changed to give different ring diameters and thickness, and some systems are available that allow the ring diameter and thickness to be totally variable. Foresights may have elevation and windage adjustments built in. The rear sight is a precision piece of engineering, with micrometer adjustments for windage and elevation, usually fitted with precision vernier or micrometer scales graduated in fractions of a Minute of Angle.

Peep-holes are variable in diameter and colour, and polarizing filters can be included, as can correcting lenses. Whilst appearing crude in principle, these sighting systems are incredibly effective, and capable of fantastic accuracy.

For a clear graphical depiction, see here for a diagram of sight pictures.

The ultimate sighting system for any rifle is the telescopic sight. A failing of the dioptre system is that it relies on the eye of the shooter and its ability to accommodate, that is the ability to switch from focusing on the target, to focusing on the foresight. In poor light, or with less than perfect eyesight, this is very difficult. The solution is the telescopic sight. This is a telescope mounted on the rifle, that give the shooter a magnified image of the target. Onto this image is projected an image of the cross hairs. This image is movable, to allow for elevation and windage adjustments. In theory, all the shooter has to do is align the cross hairs with the centre of the target and squeeze the trigger.

Telescopic sights have long been popular on sporting or game rifles, however target shooting demands a very special type of scope.

It usually needs:

 

  • High levels of magnification.
  • A means of adjusting the focus to accommodate different ranges.
  • The ability to focus at all ranges out to 1000 yards and beyond.
  • Accurately calibrated and easily adjusted windage and elevation adjustments.
  • A very wide range of these adjustments, to cater for a large spread of ranges e.g. from 100 to over 1000 yards.

Until fairly recently, very few scope sight manufacturers catered for the target market - it was just too small. Those target shooting scopes that were available were rare and expensive.

For this reason, in most UK NRA and NSRA disciplines, telescopic sights are not permitted.

For many year the Americans have practices a sport called bench rest; where the person who shoots the smallest group is the winner. Rifles are shot from a bench, sitting on heavy front and rear rests. The shooter is seated, and his only input is to position the rifle, adjust the sight, load and squeeze the trigger.

Bench rest demands the ultimate rifles, and scopes. Whilst popular in the US for years, bench rest is now flourishing internationally. This means that many more scope makers are producing target-grade telescopic sights.

In the UK, the only NRA discipline allowing scopes was Match Rifle: widely seen as the F1 of NRA competitions, but all this has changed with the introduction of 'F' Class shooting. Started by the DCNRA (Canada's equivalent to our NRA) at the instigation of a Mr. Farquarson, 'F' Class lets you use any sensible calibre rifle and a scope sight. The NRA has adopted 'F' Class, as has the rest of the British Commonwealth rifle associations. Suddenly, there is a demand for top-notch target scopes.

There have always been several quallity scope makers, particularly Leupold (US), and Schmidt and Bender (Germany), but in the past few years there has been almost an explosion in the range of suitable scopes available to the UK shooter.

Leupold and S&B are still very good, but their products can cost well over £1000. A relative newcomer, Nightforce, sets the standard; an Australian company, their scopes are made in Japan, and are excellent. Sadly, you get little change from £1500.

As of yet, nothing much seems to be coming out of Russia, but look out for IOR, a Romanian, ex Soviet era military scope maker. Quality is very high, with prices around the £1000 mark.

For the more humble of us, we can look to Japanese, Taiwanese, Korean, and increasingly Chinese makers. Here are some names to look for: Nikon, Nikko Sterling, BSA, Hawke (distributed by Deben in the UK), Burriss, Bausch and Lomb, Tasco, ZOS - a Chinese manufacturer also produce good quality budget priced scopes around the £100 mark.

Scope Mounting:

 

There are various methods for attaching a telescopic sight to your rifle. If you are lucky, your rifle may have an integral scope mounting dovetail machined into the top of the receiver. Most .22 lightweight sporting rifles have such a dovetail, and fitting a scope consists of fitting appropriately sized scope mounting rings to the dovetail and fitting the scope into the rings.

However, what do you do if your rifle has no such dovetail rail?

 

Simple: you need to attach a mounting rail to the top of the receiver, and then mount the scope rings onto that rail.

Home made scope mounting on an Enfield No.4 action.

If your receiver is already drilled and tapped for fitting a scope rail, then you can fit a rail using these attachment points, but many rifles will have no such provision. In this case, unless you feel confident and competent to do it yourself, a trip to the gunsmith is in order.

Where do you get a scope mounting rail?

If you have a rifle based on one of the American actions such as Remington, Winchester, or one of the many clones of these actions you should be able to obtain a rail to fit from a target rifle specialist. Some target rifle actions are built to Remington dimensions (for example, the RPA Quadlite action) is the same size as a Remington, so a factory made rail to fit should be available. If nothing is available, then it’s a case of doing it yourself, or having one made. There are a few gunsmiths who specialise in target rifles, and any of them can under take the work.

At the moment, there are a wide variety of scope rail types, all with different profiles, which can make getting hold of the correct mounting rings difficult.

Probably the most popular mounting system is the ‘Weaver’ rail - a wide, trapezoidal section rail, which is dimensionally the same as the US Milspec ‘Piccatinny’ rail.

Weaver rail mounting on top of a highly modified Enfield No.4 receiver. Picatinny/Weaver rail mounted on a P-H M87 action. Weaver rail mounted on a Marlin Model 1894.

 

Mounting for long-range shooting:

Most scope mounting systems align the optical axis with the bore of the barrel. This is fine for medium and short range shooting, but when ranges get out to 1000 yards, the scopes internal elevation turret may run out of adjustment (especially if the scope only has a one inch body tube), making it impossible to shoot at long range. The solution is to raise the rear mounting of the scope.

Please do not put packing or tape in the bottom half of the rear ring mount. Whilst it might achieve the result, it will almost certainly bend or distort the scope body.

The solution is to fit an inclined scope mounting rail. Whilst you are making or having made, a scope rail, ask for it to be made with a 20 minute (1/3 of a degree) taper from front to back. The rear of the rail needs to be higher than the front.

Some pictures of scopes, mountings, rails and rings are included in the gallery. Some of them are home made, some are proprietary. All of them work.

Included are some pictures of home-developed solutions to scope mounting on Lee-Enfield No.4 actions, a difficult job as the No.4 has no top to its action, and nothing to fit a mount base to.

A Guide to Altering Your Scope Rail Inclination:

As already said, putting packing inside the rear scope ring to elevate the scope is not a good idea; distortion of the scope tube is likely. Some people put shims under the rear dovetail or scope mount if a two piece mount is used. Whilst better than packing the rear ring, this method is still likely to put a bending strain on the scope tube. The best method is to use a tapered, one piece rail, but what if you have a one piece, untapered rail?

The solution here is to place shims under the rear of the rail, between it and the receiver of the rifle.

How thick should the shim be?

Most people find that a scope inclination of 20 minutes (20’) is adequate, and will allow most decent scopes to elevate from 300 to 1,000 yards. 20 minutes is a small angle (it’s 1/3 of a degree), so to get this inclination, we only need to put a very thin shim under the rail.

Say your scope rail is fixed to your receiver by screws, one at the front of the receiver, and another at the rear. Put your shims under the rail, adjacent to the rear screw.

How much shimming?

Here is a simple formula: measure the distance between the mounting screws,

The thickness of shim (in inches) to give 20 MOA inclination is given by 0.006 X D, where D is the distance between the mounting screws in inches.

In other words, for every inch distance between the mounting screws, you need to shim up the rear by 6 thousandths of an inch (6 thou'). So if the screws are 4 inches apart, you need to shim up the rear by 24 thou'.

Where can I get shims?

The average drink can is made of stainless steel or aluminium 6 thou' thick. So, have one on us, and cut your can up - a pair of scissors will do the job. In our example above we would need 4 pieces, cut to about the size of a postage stamp. Loosen the rear screw, and slip the shims in, tighten and the job is done.

 

Shotgun Sights:

Shotguns do not uses the same sight system as rifles, instead having a coloured 'bead' at the muzzle end of the barrel. There is no physical rear sight - instead this role being served by the shooter's eye position. As such, the stock must be adjusted to fit the shooter to allow correct eye placement.

 

 

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