Surplus Rifle Sight Tips

kraigwy

New member
Over time there have been several post about surplus rifles shooting high. Many were used with the bayonet attached and sights adjusted accordingly so I thought I would provide tips for correcting this problem.

In the Spring 2011 Issue of the Grand Collectors Assn Journal there is an article regarding the difference of impact while the three different bayonets are mounted on the rifle. Basically it shows that the length of the bayonet and how it's mounted determines if its high or low.

A lot of us collect bayonets but few actually shoot the rifle with the bayonet so we want to adjust the sights to shoot the rifle w/o bayonets.

First we must remember, change the rear sight in the direction you want the impact to go, change the front sight OPPOSITE the direction you want to go.

The question is HOW MUCH? This information is provided by the CMP GSM Master Instructor Program.

It doesn't matter where we sight in the rifle as long as we know 1 MOA = about 1 inch at 100 yards, (1.047) 2 at 200, 3 at 300 etc etc.

We want to know how much to move the sight to adjust for one MOA.

For one MOA the change needed in thousands equals the sight radius divided by 3600 (100 yards = 3600 inches). Sight radius is the distance from the rear sight to the near corner of the front sight.

An example: The 1903A3 has a sight radius of 28 inches. 28/3600 = .00778

So if you are shooting 3 inches high (or low) the sight has to be changed
3 X .00778 = .02334

This works for windage also, depending on the rifle, the front or rear sight can be drifted left or right.

Also depending on the rifle, there are various ways to change the sights to keep the rifle "AS ISSUED", an example on the Springfield you may have to file down or replace the front sight (depending on if its shooting high or low).

On the Mosin 96/30 you can file down the front sight (if shooting low) or grin/mill the bottom portion of the slider on the ladder rear sight.

Hope this helps shooters in shooting these old work horses. (it works on modern rifles also).
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thesheepdog

New member
Since I am still waiting for my Service Grade, I am unfamiliar with the Garand.

How does impact change with a bayonet? Is it barrel harmonics or what?
 

kraigwy

New member
How does impact change with a bayonet? Is it barrel harmonics

Pretty much. It depends on the mounting and the length (weight) of the Bayonet and the bayonets center of gravity. The M5A1 isn't affected as much as the other two. It has a shorter blade and used the gas plug screw for mounting, not the barrel.

The M1 Bayonet also tends to shoot about 6 inches low. The M1905 Bayonet tends to shoot quite a bit high.

How much of course depends on the individual rifle.

Changing the sights on the M1 is a lot easier to sight in without modification allowing you to use the witness mark on the left side of the rear sight base. Simply sight it in at the desired distance, the set the witness dial mark for that yard line to the mark on the sight base.

Since I am still waiting for my Service Grade, I am unfamiliar with the Garand.

There is a lot of great information avialiable to members of the Garand Collectors Associaton.
 
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