Sighting in a rifle
All long-range sighting in and shooting requires a portable bench and proper rifle support front and rear

The basics of sighting in your rifle

How you should sight in a rifle, and over what distance, is a matter of some debate and depends on a number of factors, including the terrain, which may vary the distance involved. 

In the days before computers, it was generally considered that a big-game hunting rifle should be sighted to hit 3” high at 100 yards, the equivalent of 8.3cm at 100m. 

Sighting in a rifle
Projectiles with high BCs such as these AccuBonds (.435) will increase range

This was, and still is, a reasonable figure for a rifle such as the .30-06, .270 Winchester and .25/06. Consider the results of these nominal loads and speeds:

  • .30-06: 165gn projectile, BC of .475, at 2900fps gives a zero range of 260 yards (238m)
  • .270 Win: 130gn projectile, BC of .433, at 3000fps for a zero range of 275 yards (251m)
  • .25-06: 120gn projectile, BC of .391, at 3050fps for a zero at 270 yards (247m).

It is interesting to note the closeness of the three distances. 

I have used similarly generalised guidelines with other rifles in the field with success. 

Perhaps we should start at the beginning with lever-action rifles in .30-30 Winchester and .45-70 cartridges. These two are kings of the swamps, and the decision is easy: sighted in to be dead on at 100 yards, you cannot go wrong. 

If you pair the lever-actioned hunter with another shooter using a cartridge such as the .270 Winchester, they can cover a lot of territory on a swamp edge. 

Things get murky when we move out to longer ranges.

For really long-range work, including any small targets at excessive range, you need at least a portable bench to be successful, along with support for the rifle, both front and rear. 

Sighting in a rifle
Minimum gear for accuracy includes a bipod and rear sandbag

Almost invariably, such long-range shooting is aided by a ballistic drop chart plus an electronic rangefinder to accurately range the game. This is sometimes difficult with small targets, such as rabbits.

Irrespective of distance you’re sighting in for, it is vital that there is some support for the rifle to ensure a solid sight picture. At the very least, there should be a bipod and possibly a rear sandbag to ensure firearm stability. 

The sighting-in target should be composed of squares; usually one-inch squares for 100-yard shooting or 3cm squares for 100m sighting, which in both cases in approximately minute-of-angle. 

This allows accurate movement of the projectile, which is necessary for accurate sighting. 

Most telescopic sights have movements that are ¼” per click, 1cm per click or ¼ MOA per click, so you can be quite precise in setting them up. Some have even finer adjustments for more precise long-range shooting.

Sighting in a rifle
A target with squares of a known size is needed for accurate setting up

One necessary piece of gear is a chronograph; without one, you are simply guessing. It just has to record velocity faithfully and does not require bells and whistles. 

You should also record your setting for each individual rifle plus the projectile in use at the time

Projectile selection should also consider the type of game to be encountered; there is still a place for the basics, such as a traditional flat-based soft point, or for shorter ranges, perhaps a flat-based round nose.

Take your time with the whole process. It’s not a race. Spending time now to set up for the future is time well spent. 

Be very careful with settings and record each rifle and projectile combination. For long-range work you need an accurate drop chart in conjunction with an electronic rangefinder.




Like it? Share with your friends!

What's Your Reaction?

super super
fail fail
fun fun
bad bad
hate hate
lol lol
love love
omg omg
Ron James