Firearms Talk banner

Adjusting the front sight of a military rifle

2K views 12 replies 9 participants last post by  hairbear1 
#1 ·
I made this simple image to show what a rifle is doing.
Lets say it is shooting high and to the left. The target is 100 yds and the point of impact is about average 9 inches high and 7 inches to the left. Ballpark.

The rear sight is a ladder sight and is already set at 400 meters because when it was set at 0 to 100 the rifle shot very low. I think I had to do this because of a short front sight?
------------------------------------------

The front blade looks to be filed shorter than original or it is not a good match-up for the rear sight as it is not original.

There is a dovetail and locking screw for the front sight.
There is no windage adjustment for the rear sight, only elevation.
So any windage has to be adjusted at the front end.
------------------------------------------
Now, my theory is that I need to:
A. get a taller blade
and
B. Move my front sight to the right. ( meaning the righthand direction looking down the barrel through the rear sight )

Am I Correct? I can never figure this stuff out and remember a rule.

Now here is an image of my front sight and here is an image of a replacement that appears to have a taller blade. And finally the image of my illustration.

Thank you very much. Hope I explained this clearly enough.
 

Attachments

See less See more
3
#2 ·
not knowing the caliber, what ammo are you using?

reason is, IIRC your rifle is a military surplus rifle of some sorts? and if you are using ammo that has bullets heavier or lighter than the military version that was used in the rifle, it could cause a shift in the POI of the bullets.

looking at the sights, one does seem to have a taller blade than the other. that too could be part of the problem.

and how do you adjust for the windage of the front sight? that could be an issue as well.

best i can come up with on short notice! :D
 
#3 ·
Dallas, you have been a pal. Of course this is the a spin off from my Krag project saga you might recall.
The ammo is handloaded by myself. 30-40 Krag Cast powder coated flat nose gas checked 200 gr over 28.5 gr Varget.
I have another Krag sporter and they shoot great in both rifles. The group is pretty tight. I think it is the front site that needs moved. It is a dovetailed sight with a locking screw in front.
I think I have located a new screw.
Springfield 1903 1903A1 Rifle Front Sight Base Screw. When the screw is loosened the dovetail can move left and right and then set in place by tightening the screw again. ( Mine is ruined ) But I have shown an image I found of what I am pretty sure I need.
 

Attachments

#5 ·
most military rifles pre-vietnam the sights are designed to shoot high usually about 9 inches high. this is because doctrines of the time called for a "6-oclock" hold.
 
#6 ·
Adjust the front sight in the direction the shots are pulling.
Thank you Danoobie and JonM!

Now, my theory is that I need to:
A. get a taller blade
and
B. Move my front sight to the right. ( meaning the righthand direction looking down the barrel through the rear sight ) WRONG WAY!
So what I need to know is if a taller front blade, holding at 6 o'clock POA,
make the POI higher or lower, as I want to take my rear sight back to the 0 to 100 adjustment rather than at 400 meters where it is now.

I know this is elementary geometry, I know I should be able to wrap my mind around this in a snap but it isn't clicking for me, at one time it would have been easy but I'm sure it has a lot to do with getting older.
 
#9 ·
Shot this about a week ago with the taller (new) front site installed, with the rear sight set at lowest setting and the rifle shot quite a bit lower than it did with the old (shorter) front sight.
So I now know why the shorter (original) one was filed down.
I am going to leave it as it is and adjust my rear sight to the height that it shoots correctly at the 6 o'clock hold. The distance settings on the rear ramp and ladder sight would still be off regardless, so I'll just make a note of what it shoots right at, and keep the note in the hard case that I keep this rifle in.
If there's anything good to come of this, I learned that a taller front sight will lower the point of impact.
 
#11 ·
U. S. Military rifles - since the M1892 Springfield (Krag-Jorgensen) - were made with replacement front sights posts to be replaceable. The front sights were of different heights to adjust elevation.

Understand, the rifles were intended to shoot issue ammo. Therefore, the sights were intended to match, front to rear and cause issue ammunition to strike the appropriate place.

So your home brew ammunition may never match up with the original sights. (Not that your ammunition is defective, just not matching up in trajectory with the issue stuff.)

Replacing your front sight insert, or post, may be a hard trick. Might try Brownell's or the used parts places. OR, you might be able to 'make' one from steel stock. (Filing or machining, depending on your skills and determination.)

A taller front sight will make the rifle shoot lower. However, theoretically, when the 'correct' front sight is installed, then all the other rear sight settings will be correct for their respective settings. To do this correctly, one must be shooting at the 100 yard mark with the sight at the 100 yard setting. AND, one be shooting the issue ammo.

Rule for sight correction is: Rear sight moves direction the shooter desires the strike to go. Front sight is moved to follow the strike of the bullet. Rear sight leads, front sight follows.

The front sight can be 'drifted' left and right to set the windage at 'zero'. I have an M1898 rifle and the rear sight is adjustable for windage by loosening a screw and manually moving the entire rear sight. (It's a pain to move the rear sight just a little.) That feature was not included on all the versions of the Krag. Than again, my front sight base is built into the barrel; no barrel band.
 
#13 ·
I found with my Mk3 No.1 SMLE hand loading 180gn Sierra Pro Hunters that setting the rear sights to 200yards an dusing about a half blade and aiming just below the bullseye at 100- to 200 yards it would hit centre or close enough to it. Luckily I didn't have to adjust front sights but in the 1 or 2 open sighted rifles I also have if it's shooting left I tap the sights across to the left.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top