Files are not for windage adjustment

I mentioned in a previous post here how a previous owner of my Carcano had made a windage adjustment to the front sight blade by means of a file. That blade is driftable. No need for files. At any rate, the POA at 50 yds is off the POI by about 12″.

This blade is next to useless. Grrr
This blade is next to useless. Grrr

If you own a rare military rifle from WW II, please don’t do this to it.

I could try to drift the sight over to compensate, but it is clear that the blade has been filed down beyond where it ought to be. Too much material has been removed and I think its time to get a new one made.

Now I don’t have machine tools sufficient to fabricate my own blade, but my cousin does. So the old sight and a new drawing are in the mail off to him. Hopefully he can do something with it all and I can have a good foresight again.

The internet is a useful tool when it comes to research. However, I have been unable to locate specs on the foresight itself, or a replacement part, for this rifle. This poses a challenge for us in that the Carcano does not use a standard sight picture. The blade and the rear v-notch are not supposed to be in the normal alignment. Normal sight alignment means that the front post covers the target and is centered in the rear sight. The top of the front post and the top of the rear v-notch are aligned as well. In most configurations this gives the shooter a 100yd POA.

Not so with the Carcano. As can be seen in the picture below, the Italian designers had a different idea, and when you get the logic of it, it is rather sensible.

Italians are weird. But we love them just the same...
Italians are weird. But we love them just the same…

In combat, a rifleman doesn’t always have the time to adjust his sights when aiming at targets between 100 and 300 meters. A method of fast target acquisition is needed, and it should be simple.

The solution found by the designers was to make the sights in such a way as to be able to use them unadjusted for shooting out to 300 meters. The rear sight ramp doesn’t even start until 600m. All the shooter needs to do is set the front blade in the bottom of the v-notch for 100 meters, and in the classic alignment for 300 meters. If the shooter (myself, in this case) understands this doctrine, accurate shooting should be relatively easy.

Because I cannot find the part for sale online, I am trying to get one made. Last night I sat down with calipers, paper and pencils. This is what resulted. Hopefully It works.

It may be rough, but all the required measurements are there... I hope.
It may be rough, but all the required measurements are there… I hope.

A rough drawing can be worse than no drawing at all… One of the key things will be to bring the height of the blade back to 0.441″ from 0.358″. If I need to file it down I can do that easily enough, but as far as I can tell, this is the height that it is supposed to be. With a square top I shall be able to get a decent sight picture and drift the dovetail as needed.

By the way, I used the ‘Sight Height Calculator’ on Brownells website to figure the height out. They feature a very handy calculator and I recommend it to anyone who may be interested. The calculator can be found here. For the rear sight height I put in the measurement to the bottom of the v-notch, as that is where the 100 meter zero is supposed to be on this gun. Hopefully all goes well and I will have a functioning gun soon.

I'm not a pro draughtsman, but I like to pretend
I’m not a pro draughtsman, but I like to pretend