M1 Carbine Help Needed

[Enfield47]

I took my M1 carbine to the range today and was having a problem with it shooting really far left - about 10" off center at 100 yards. My friend shot it and was having the same problem, so at least it wasn't just me. I was shooting my handloads, 100 gr plated RNFB, 14 gr Win296, and Tula SRP (I didn't have any factory ammo with me). I've had it out for only two other range trips and I had a similar problem on the first outing using factory ammo but discounted it because of it being really windy that day. The second time I was shooting at a large metal gong around 100 yards away and didn't notice the problem (but it might have been present).

I stripped it down and everything looks ok. Both sights look like they are on straight and centered, the rear sight has the windage adjustment. It was in the center position when it was shooting to the left, when I moved it left it was marginally better. I am at a complete loss here. Any ideas what could be causing this?

[ccandgc]

Sounds like the rear sight is off. The whole rear sight needs to be moved left(or is it right?). Then fine tune with the windage.

[smle-man]

slightly bent barrel? You can drift the rear sight assembly to the right and re-stake it once you are zero'd.

[C&Rtrader]

Is it a blue sky "import?" look for markings near end of barrel.

[Eagle76]

Moving rear sight on M1 Carbine

Move the sight to the RIGHT. However, you will probably need a Carbine rear sight tool. You may be able to tap it with a brass hammer and wood block but better to buy the tool on line to move the sight.

[C&Rtrader]

Should have mentioned, and why i asked, I heard blue sky bent some of the barrels when they stamped them.

[Enfield47]

I'll take a look at the rear sight tomorrow and see if it is staked or not. It looks like it's centered, would pics of it help? I'll see if I can find a rear sight adjustment tool online, I think there was a thread on it recently.

The barrel doesn't look bent, I held it against my safe to have a flat surface for reference and it looked straight. The crown is a bit knicked, could that have such a dramatic effect?

There are no import marks, I think it might have come through the CMP originally.

[smle-man]

A good crown is the most significant part of rifle barrel accuracy. Perhaps it needs recrowned if it isn't clean and sharp.

[Black Majik]

not familiar with M1 Carbines, but can you drift the front sight? Drifting the front sight to the left will shift your POI to the right assuming you're unable to adjust windage on your rear sight.

[CEDaytonaRydr]

not familiar with M1 Carbines, but can you drift the front sight?

No. Unfortunately not...

To OP: Did you move the windage as far over as it can go? I would try to zero it with the windage adjustment, if possible and move the rear sight if that doesn't help. DO NOT try to bend the barrel!!!

I wouldn't worry about re-crowning yet either. Once you zero, see how consistent it is. If it's inaccurate, puts keyholes on the paper, or appears to show physical damage on the muzzle, then you can think about re-crowning.

[Mud Eagle]

It is very typical to have M1 Carbine type 2 or 3 (those are the types with adjustable windage) cranked off center to shoot "straight". Not an indicator of there being something righteously wrong with your Carbine.

I have owned several M1 carbines (both "reputable" CMP guns and the "evil" Blue Sky imports), and about half of them needed the windage at least halfway to the left-side stop to hit POA at 100 yards. The Blue Sky guns had nice barrels, too...and the affliction was to both the CMPs and the Blue Skys.

Anyway, crank away until you get POI=POA.

If you really want to troubleshoot the issue:

- Check barrel indexing (via two handy index marks on the bottom of the barrel and receiver where they meet)
- Check barrel straightness
- Check barrel crown

[Enfield47]

I didn't have the rear sight cranked all the way left so I'll try it all the way to the left and see how that works. If that doesn't work, I'll see about getting the rear sight tool and moving it over to help compensate. It's interesting that this is somewhat common with the M1 Carbines to need so much adjustment.

No worries about trying to bend the barrel, I wouldn't even consider that option. LOL The bullets all left nice round holes in the target and frame, no keyholes, so at least I can tell they weren't tumbling.

[ccandgc]

If you are in or near San Diego, I have all the M1 Carbine tools.

[2761377]

[QUOTE=Enfield47;13135658]I didn't have the rear sight cranked all the way left so I'll try it all the way to the left and see how that works..../QUOTE]

if you want bullet impact to shift to the right, move the rear sight to the right. if you crank the windage adjustment all the way to left, bullet impact will move the the left as well.

for both elevation and windage adjustment, move the rear sight in the direction you want bullet impact to shift

[Enfield47]

If you are in or near San Diego, I have all the M1 Carbine tools.

Thanks for the offer, I'm about 90 minutes north of you in LA county. I'm going to take it to the range next weekend for the WEGC C&R shoot to see if I can adjust it enough. If I can't, I'll be in touch.

[QUOTE=2761377;13135871]

I didn't have the rear sight cranked all the way left so I'll try it all the way to the left and see how that works..../QUOTE]

if you want bullet impact to shift to the right, move the rear sight to the right. if you crank the windage adjustment all the way to left, bullet impact will move the the left as well.

for both elevation and windage adjustment, move the rear sight in the direction you want bullet impact to shift

Thanks for that, I had it backwards - I'll move it all the way to the right. I keep confusing it with front sight adjustments which are opposite.