09 January 2006, 17:35
Mike in SCNeed Help
I have a friends Universal M1 carbine to try to figure out why it shoots so high. One foot high at 30yds., three feet high at 100yds. Adjustable rear sight set all the way down, everything looks stock and undamaged.
I have tried Norma and Winchester ammo, both the 110gr fmj. Is there a way for an amateur to tell if the barrel is bent? I looked, but couldn't see anything definitive. Thanks, Mike.
09 January 2006, 17:56
BbearTry raising the rear sight.
09 January 2006, 18:05
RojelioSeriously, you may need a taller front sight.
A bent barrel can be seen with the naked eye by looking through it.
If it looks straight looking through it, then it probably is.
Rojelio
09 January 2006, 18:18
conchoTake bolt out ,look threw barrel at light 10 ft away and you will see dark shadows inside barrel if shadow is broken it's bent or has object under it making it bend ! best way is to strip all stock area away from barrel to check B Bear is just kidding !ammo is not your problem !
09 January 2006, 21:21
Mike in SCThanks for the replies. I have asked this question on other forums, and have always had someone suggest raising the rear sight. I guess I need to figure out how to take this down and look really hard...
09 January 2006, 22:10
El Deguelloquote:
Originally posted by Mike in SC:
I have a friends Universal M1 carbine to try to figure out why it shoots so high. One foot high at 30yds., three feet high at 100yds. Adjustable rear sight set all the way down, everything looks stock and undamaged.
Thanks, Mike.
You need a higher front sight to make the shooter drop the muzzle some when aiming! This is a very common, basic problem.
I would NOT go trying to bend the barrel!!"Formula:
Amount of Error (inches) X Sight Radius(in.)/Distance to Target (in.) = Sight Correction Needed (in.)"
If you are shooting low, you would replace your front sight with a lower sight, and conversely, if you were shooting high, then you would replace your front sight with a higher sight.
Add or subtract the number of thousandths needed to the actual present height of your front sight and you will have the height the sight must end up at.
Example:
You say at 100 yards, your shot is 3' (36") high, and I am assuming the distance between your front and rear sight is 18".
36X18/3600 = 0.18", so 0.18" must to be added to the height of that front sight, if that carbine has exactly 18" between the rear face of the front sight & the center of the rear aperture. This would bring it to dead-on at 100 yqrds with the rear sight left all the way down.
I'd probably add 0.2" to the front sight instead of 0.18", to give a little latitude in elevation adjustments, just in case he wants to use different ammo from time to time.
Let us know if this works.
09 January 2006, 22:16
El Deguelloquote:
Originally posted by Bbear:
Try raising the rear sight.
Poor sugestion-this would RAISE the point of impact, which is too high already!!, with the rear sight all the way down!!
RULE: Move the rear sight
in the direction you want to move the point of impact; Move the FRONT sight
in the opposite direction from the direction you want to move the point of impact!10 January 2006, 05:20
Mike in SCYou need a higher front sight to make the shooter drop the muzzle some when aiming! This is a very common, basic problem.
I would NOT go trying to bend the barrel!!I wouldn't try to bend a barrel, just check it to see if it is. As far as a taller rear sight, I wouldn't know how to go about that. I haven't been able to find any spare parts for a Universal brand carbine. The collector types all seem to hold them in low regard as they are not "mil-spec."
10 January 2006, 21:36
MarkAnother option is to build up the existing front sight with JB weld, marine tex, or similar epoxy. If you do a good job it should look OK. Or you can try soldering a brass bead or rod to the front sight, or super glue a fiber optic piece to it (make oone from a pin of an old bow sight, go to an archery shop and I'm sure they'll give you a broken pin).
11 January 2006, 05:30
Mike in SCExcellent ideas, and no, I wouldn't try to bend the barrel! I just recently started to think about JB Weld or some other epoxy. I am very impressed with the formula for calculating the change in front sight and copied it just to have it. Thank you for your help. I may get this thing fun to shoot after all.