zero an m1 carbine

[cobra 22]

Hi. I'm new around here, and was wondering if anybody has a clue as to how to zero a USGI M1 Carbine. Mine has the sliding rear aperture, and the increments (from front to rear) read, 1 2 25 3. There is also a little screw on the back of the sight along with some vertical marks. Any help would be appreciated

 

[Firehand]

The 1, 2, etc. are range marks: with the aperture slid down to 1 it should be on at 100 yards and so forth. The marks on the back are for windage, one mark over is so many inches/fractions at 100(offhand I can't remember the mesurement).

 

[gunny1022]

You will find the carbine shooting high at ranges less than 100 yards. You can add some height to the front sight with liquid metal to lower your hits.

 

[ArfinGreebly]

And Me Without My Manual

I do believe . . .

What I've been told, and still not verified, is that if you zero the M1 Carbine at 25 yards you will be high at 50 yards and zero again at 100 yards.

Depends on which generation rear sight you have where your arc intersects occur.

If you find out before I get mine back I'd like to hear about it.

The sight you describe is the same as mine. The sliding bit is elevation (or range distance if you prefer), and the little screw thingy is your windage (left/right) adjustment.

I recommend setting up your paper at 25 yards. Get on the paper. Move target to 50 yards. Refine your adjustments. Move target to 100 yards. Do final tweaks. If the arc is what I've been told, and you get a good zero at 25 yards, you should be an inch or so high at 50, and good to go at 100.

I won't have mine back for weeks, so I can't do that experiment just now.

 

[cobra 22]

I went out and shot about 3 mags worth today, and at 25 yards I was about an inch low and and inch left. It was pretty much the same at 50 (even though I was shooting downhill). The slide was set at 100.

I have the windage knob on the left side of the rear sight, as well as the little screw on the back. Am I correct to assume that the screw is for fine adjustment?

 

[dfariswheel]

The little screw is so once you get the windage set, you can loosen the screw and move the tiny scale until the center line lines up with the sight index mark.

This is to prevent confusion about where the sight is set for windage, if the scale is centered. If you center the tiny scale, you can always tell where zero windage is.

The sight slide is in 100 yard increments.
1 is 100, 2 is 200, 25 is 250 and 3 is 300 yards.

If your carbine is shooting low at 100 yards, the front sight was intended to be filed down until it targeted.
If it shoots high, you'll need to buy a new GI front sight that hasn't been trimmed.

 

[Trebor]

Be aware that you may need to rezero after you remove the action from the stock. The tension on the recoil plate affects the zero and accuracy and it's hard to screw down the recoil plate exactly the same every time. I try to leave my carbine in the stock as much as possible. I only do a complete field or detail strip for cleaning about once a year.

 

[lmccrock]

If it shoots high, you'll need to buy a new GI front sight that hasn't been trimmed.

I do not have the manual handy, but they were generally expected to shoot low and the arsenal was supposed to file down the front sight. So when mine was shooting way high, I looked into replacing my front sight with a new, untrimmed part. Turns out mine has the untrimmed front sight so to get it on target I would have to add metal as previously mentioned.

Lee