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View Full Version : M1A sight issue..please comment


old-trapper
03-04-2009, 8:49 PM
I have had and shot M1A -M14 style weapons for over 20 years. I just ran across a issue I have never seen. Maybe you guys have. the gun is a Fed Ord M14 SA receiver with misc surplus parts... complete gun. It has had some gunsmithing done, glass bedding and soldered gas cycl. The gun will print a HONEST 1" group at 100 yards with a gen 2 scope mount and crappy scope. Here is the clincher......you cant get it to adjust low enough with the iron sights to get in the bulls eye. The guy put a tall front sight on it and still cant get it in the black.. Any info from any of you old salts would be helpful. Im going to start from scrath in the A.M. with surplus ammo instead of his hand loads and a LARGE piece of paper and see what is going on but any heads up for what to look for would be great because this is a new one for me. Every M1A i have ever seen seems to be close 7 clicks up let alone all the way down.

30Cal
03-05-2009, 10:54 AM
The Scout uses a pretty tall front sight--I think it's actually the sight from an M79 (track down Bill Ricca's website).

You can also see if you can get more downward travel on the aperture by filing off the very bottom toothless part of the rack.

It may be possible to bed it with so much pressure up at the forend that you can't get elevation, but I can't really see losing more than 2-3 minutes that way.

If you're unable to compensate for it, then your reciever most likely has issues.

ripcurlksm
03-05-2009, 1:12 PM
Similar issue on my M1A Scout last night at the range. Trying to get my 25m / 250m zero going for an outdoor shoot this weekend...

With the rear sight all the way down at 25m, i was shooting about 2" low of the bullseye. The Scouts have a NM front sight on them, so I was thinking about raising the front sight a little bit, but not sure now much to go. I know for my 25m zero, I should be shooting ~4" above the bullseye, so that means I have to move my front sight up enough to cover 6" on paper (2" up to get to bull, then 4" more to get to 250m zero).

Any advice?

-hanko
03-05-2009, 2:47 PM
With the rear sight all the way down at 25m, i was shooting about 2" low of the bullseye. The Scouts have a NM front sight on them, so I was thinking about raising the front sight a little bit, but not sure now much to go. I know for my 25m zero, I should be shooting ~4" above the bullseye, so that means I have to move my front sight up enough to cover 6" on paper (2" up to get to bull, then 4" more to get to 250m zero).

Any advice?
My advice would be to raise the point of impact, you'll need to move the front sight DOWN. Alternatively, you could RAISE the rear sight. You could also do both.;). Acronym is "FORS"..."front opposite, rear same"...obviously referring to poi movement vs. sight movement.

-hth;)

-hanko

ripcurlksm
03-05-2009, 2:53 PM
thanks makes sense hank, thanks

tteng
03-05-2009, 7:06 PM
Don't own a M14 (I do have an accurized Garand, glass-bedded and all), and this is how I think,

1. If my Garand is 1MOA w/ hand-load, any other load (standard charge, not reduce-loads) will probably not improve the grouping much, surplus-ammo included, so why change the load.

2. It's accurized and bedded, and it's a tack driver but shoots high. If I mess w/ the bedded stock/receiver, I'll probably de-accurize it. And I'm no gun-smith, so I'll probably leave it alone. That leaves, either 'lower the rear sight', or 'raise the front sight'.

Option 1 'lower the rear sight': I have to open up the rear-sight assembly, and see if I can do something about the teethed aperture. If, at lowest setting, there is no more 'teeth' left on the travel, then there is nothing I can do. However, if, at lowest setting, there are still 'teeth' left (maybe it's an after-market item) bec the apeture tail is bumped into something, then perhaps I can file off some of the aperture tail for full travel. Chances are it's probably not it, and I don't feel comfortable messing its mechanism. So that leaves getting the front-sight taller.

Option-2 'raise the front-sight': First, find out how much taller the front sight should be. (For example: if eye-ball to front-sight distance is 24-in, and eye-ball to target is 3600-in (100yrd), then to drop 6-in at the target, the front-sight has to go up by 0.04-in, roughly speaking.) Once you know how tall your front-sight should be in reference to what you have- then you can call around if someone sells taller sight (probably $100 or so), or you can home-cook something yourself. I'm pretty cheap, so I'll do the following.

Take some steel-shim, cut and file it down to the size I want (a bit taller for starter), JB-weld it to the blade tip, zero the rear-sight and shoot for elevation (the group should start out low), bit-by-bit file away the tip until the shot-group is at my zero-aim, then pretty it up. Kinda hokey, but it should work.

Just my 2c.

old-trapper
03-05-2009, 8:22 PM
thanks for the input...rear sight is bottomed out in the sight base so it is not going anywhere. It will be very interesting to see if this rifle is shooting up hill IE little or no drop out at distance. that would make me think reciever. Looks like my only option is going to be front sight. the only reason i would mess with the ammunition is if it is too hot. I dont have his formula but i think it was too slow of a powder for a m1a. he said it was his.308 hunting load. I am hoping that surplus brings it down to the black even if the pattern is worse. Then go from there with the load

old-trapper
03-05-2009, 8:29 PM
i have a barrel straightness gauge for ar but not for .308 that might be a thought as well...