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Problem zeroing gun

5K views 24 replies 10 participants last post by  Rivervalley0311 
#1 ·
Hey guys,

I've been having a bit of a struggle getting my gun sighted in. I'm really not sure what the problem is. I have a Remington 7600 .243 with a Nikon Prostaff 4-12x40mm scope that I cannot get to shoot accurately. At 25 yds, this gun will shoot a dime sized pattern. According to Nikon Spoton app if I zero the gun .5in low at 25 yds, it will be dead on a 200 yds. Tonight I moved out to 200 yds, and the gun is shooting all over the place (no I am not wiggling, the gun is in a shooting stand). Does anyone have any suggestions on how to fix this? Or has anyone had problems with the 7600 before?

Thanks, Colton

P.S. Could the fact that I've been shooting up ammo that's about a year old have anything to do with it?
 
#2 ·
Define "all over the place" for us. Two inches, ten inches, three feet?

I would check to make sure the bases and rings are all tight, and that the scope has not been damaged at all (does it tinkle if you shake the whole thing?). Check it all. Take it back to 25 yards and start over. Three shots there, then three shots at 100, then see what it does at 200 if that is the distance you want to use it at.

Other possibilities include mixed ammo (easy to do with a .223 and probably not so easy to do with a .243, but possible), anticipating the recoil when you fire, etc.

If you are shooting very heavy or very light bullets you may have discovered that the rifling twist is wrong for the bullets. My .243 will shoot sub-MOA with 75-100 grain bullets, and 3 foot groups with 60 grain bullets.
 
#4 ·
I've never fired a 7600. I do have a 760 though (in 270 and also 308). While 8 inch groups at 200 yards won't win any contests, it's not too far off from my expectations of my 760. I traded a Chinese SKS for it about 15 years ago as something the boys could use until they got their own rifle. Nobody shoots it any more because it's so wicked in recoil. They shot some very generic (geriatric) reloads in it.

Check you rings and bases and the scope while it's off.

Alan
 
#6 ·
The scope mounts might be getting loose. I never sighted in a rifle under 100 yds. Most of the time I sight in is either 100 or 200 yds. .5" low being dead on at 200 yds from 25 yds. doesn't sound quite right to me, but that would depend on bullet coefficient and velocity. You can look up bullet drop for the round you're shooting and check that out.
 
#7 ·
What I'm saying is, that my 760 with either of the barrels, shoots in the 5" - 6" group range on my best day with whatever ammunition I have to shoot. It has actually not even been in the field or on the bench for a good number of years because nobody wants to shoot the damn thing. My boys (3 of them) used it as a starter rifle when they began deer hunting so one of them will get it some day and they can shoot it or just stare at it nostalgically and rub their shoulder where the steel checkered butt plate left a tattoo.

You either have rings/mounts that are loose or the scope is bad. The rifle should be shooting a .244 group at 25 yards. Pull the scope off and shoot it with the iron sights and see what it's doing. I also would not use a shooting stand unless you are planning on using it in the field also. Most of the time rifles don't shoot accurately at one range and inaccurately at another, although i have run into some situations where that seemed to be the case. There was always another explanation in those situations.

Good luck.

Alan
 
#8 ·
A dime size group is about .700 od,, at 100yrds your looking at 2.8" groups assuming good conditions and fundamental marksmanship.Stretch that to 200yrds and your looking at 5.6",again assuming everything is perfect.Throw a little wind in there not so great hold and I can see 8" groups.

What kind of accuracy are you expecting at 200yrds?

Your having the same problem with your 30-06? Could it be shooter related? What is your set-up bags/bipod/leadsled?

When is the last time the barrel has been cleaned? Does it copper foul easily?
 
#17 ·
Then, there is this.

A dime size group is about .700 od, at 100yrds your looking at 2.8" groups assuming good conditions and fundamental marksmanship.Stretch that to 200yrds and your looking at 5.6",again assuming everything is perfect.Throw a little wind in there not so great hold and I can see 8" groups.
 
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#9 ·
Thanks for all the advice guys. I'm expecting to be able to drop a coyote at 200+ yards but it appears that that won't be possible from the information your guys have given me. I don't believe it is shooter error either because I have had my dad shoot it and he has the same problem. I might have to try cleaning the barrel too. I've never done it and I've had the gun for about a year.
 
#15 ·
You might try some other ammo in it. Those green box PSPs have never been tack drivers in any caliber and bullet weight I have tried. Decent, but not great. If nothing works, send it back to Remington and get it rebarreled or replaced (I assume it is a new one).
 
#16 ·
Ok let me give this a try. I have learned mainly from the military that sighting in is a procedure. Here is what I have learned. Go to the range with some good ammo preferably what you plan to use it for. Get a gun vise, and make sure the gun is clean. Since you are somewhat sighted in skip the 25 yd target and go to 50 yds. Shoot the gun at 50 yds from a gun vise. 3 shots and you should have a one inch group or less and it should be 2 inches low from bullseye center. If you cannot shoot a 1 inch group at 50yds with a vise then there is a problem. Something is loose, scope, stock or something is loose. Or the scope could be bad. I once had a friend tell the same thing when I went to the range to help him the scope was a cheap one and was not made to take the high power impact. Every time he shot it it was different, the scope was trashed and the crosshairs would move everytime.
If you have a 1 inch group at 50 yds and you move it till it is 2 inches low. Then move to 100 yds and you should be close with maybe a slightly larger group ( maybe 2 inches). Now if you are wanting to sight it at a longer range I would be looking at a ballistics chart to get some kinda idea what is happening and at what ranges. Work yourself out in stages to the yardage that you want sighted in at.
Yes there are other ways to do it and this one will work every time. By the time you are sighted in you will be confident in you weapon. No short cuts.

If this does not work find a gunsmith or a new gun.

MY .02
 
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#19 ·
.22-250 gives you some velocity advantage over .223. Other than that... If you are going to shoot factory, .223 ammo comes in a huge variety of bullet weights and brands, whereas .22-250 is much more limited. IF you are going to reload, .223 brass is fairly easy to acquire, but if you can find the components, then you can load up what you want in .22-250 just as easily.
 
#24 ·
I love my .22-250 --------- have shot a lot of `yotes, groundhogs, and a few other critters. Great accuracy and won`t wear your shoulder out. Fun caliber.
 
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