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Hecklerusp45
11-22-2015, 07:24
I have a 1944 carbine that hits 1 foot high at 50 yards and 2 feet high at 100 yards, and this is with the rear sight adjusted as low as it will go. Is there any way to fix this? I am thinking that I need a new front sight that has a taller blade. Any suggestions?

joem
11-22-2015, 07:55
I had the same problem with one of mine. I've been told that this is because when the rear sight was changed to a adjustable type the front sight was not changed. I got a bedding kit from either brownells or midway, sanded the sight to clean it. Then mixed up some of the kit and applied it making the sight taller. You can adjust it with a file, then paint it black. So far it has worked for 2 years. Others suggested a new sight.

Hecklerusp45
11-22-2015, 08:52
Thanks for the suggestion.

Rick
11-23-2015, 06:37
Check the gap in front of the trigger housing on the stock. Should have at least a 10/1000 gap between the stock and the trigger housing. If the stock touches the trigger housing in this area it will throw the group really high or low. A foot at high 50 at yards is a bunch. I would try the stock fit first before messing with the front sight.

PhillipM
11-23-2015, 07:19
The CMP has a good write up on Carbine accuracy, things to check for.

http://thecmp.org/wp-content/uploads/CarbineNotes.pdf

8) Impact Information: Carbines were assembled originally with a tall front sight that usually required lowering to sight in properly. The main cause of high shooting is a front sight shortened too much. It would be unusual if someone shortened the front sight so much that the adjustable slider doesn't center a group at some setting. Look at the front sight. Is the top up near the top of the holes in the wings? Or is the top of the front sight way below this level near the bottom of the front sight wing holes?

Richard H Brown Jr
11-24-2015, 10:06
If you don't have a copy, d/l from the net a copy of TM 9-1276 for the M1, M1A1, M2, and M3 Carbines. It's the detailed maintenance manual for the m-1 series carbines.

After you've tried what everyone has already mentioned. Read this manual and FM 23-7 (also available on the net).

http://tinypic.com/view.php?pic=2v8s945&s=5 is a modifed copy of the standard sight test target from the manuals. Print out enough copies on standard page paper.

I modified it to add the long line at the "A" sight point to make it easier to find.

The front sight is adjusted for elevation, by setting the target on the 25yrd line, and setting the rear sight at 100yrds. (rock the slider so it's tightly held on the 100yrd markers. Use a good supported firing position, and fire 7 rounds. If 5 of the 7 rounds are either cutting or within the dotted line area, the sight is within government specs. Left or right you need to adjust your windage. (remember to rock the windage adjust to make sure the detent is fully seated). IF and only IF the grouping is Below the dotted area, you have to file a bit off the top of the front sight. This is the ONLY way the elevation is corrected. If it's above the dotted area, either your sight picture is wrong, or the sight is too short, and you have to replace the whole front sight. Numrich sells the parts, and the procedure for replacing the front sight in in the TM 9-1276.

RHB

us019255
11-25-2015, 08:15
I suspect that the cause is different, but I am going to share my experience. 30 or so years ago I purchased a carbine that shot very high. I silver soldered an extension onto the front sight and got it to group fine. I and my boys shot it for many years with a DCM rifle club. Eventually, I changed my reload recipe and found that it was extremely sensitive to load. Investigation revealed through wear patterns in the parkerizing that the receiver was welded together after being cut apart and there was a strange filled hole about 2/3 of the way down the barrel. First I purchased a different receiver. That removed the requirement for an extra high front sight, but not the extreme sensitivity to load. I then replaced the barrel with a new commercial one. The load sensitivity vanished.

My theory is that the welded receiver and drilled barrel were the remains of a blank firing prop gun that some person or persons unknown had turned back to an operable weapon. Whatever the history, both the barrel and the receiver are now completely destroyed to prevent any thought of reuse.

joem
11-25-2015, 08:50
Must have been a expensice leeson. Sorry!!

MJ1
11-26-2015, 05:11
Aim low

Tuna
11-27-2015, 06:11
The best thing you can do is replace the front sight with a new one. They are available and once on you then shoot your carbine and slowly file the front sight down till you have it hitting where you want it to hit. Your front sight was originally used with a type 1 rear flip sight and not an adjustable one. The only thing that will improve accuracy in a carbine is a type 3 recoil plate and a type 3 barrel band. Nothing else will effect it like any kind of bedding or trying to tighten up the trigger housing. They add nothing to accuracy in a carbine. It was made to hit a minute of bad guy out to 300 yards nothing more.