MD DEERHUNTER

I had just purchased a new base plate and rings for my Thompson Center Encore and Nikon Omega scope. I then took the gun to get it boresighted. I went out to the range yesterday to sight-in my gun a 50 yards. I'm shooting 100 grains of 7/7 and 250 grain bullet. I was about a foot and a half low. I kept adjusting up on my scope and finally was able to get my shot a quarter-inch low of dead center. But unforturnately I'm all the adjusted up on my scope and can't go any higher. Should I go and get my gun boresighted again? Should I boresight high so I at least get on the paper? This isn't the first time this has happened to me. I would take the gun to get it boresighted and wouldn't even hit the paper. I take the gun back to get boresighted again and I'm dead on. Seems like everytime I have to get the gun boresighted, I'm always low. Never high. Any help you can pass my way will be greatly appreciated. I only have 3-weeks till hunting season.

sabotloader

MD DEERHUNTER

When you get it bore sighted has anyone check the mounts and rings to make sure they are tight???

Assuming that they are tight and I am just totally guessing but from your description - I am thinking you might have a internal problem in the scope. Do you have another known working scope you could drop on and try?

If not it might be worth buying a cheapy @ wal-mart or some such place and trying that one.

If it is the scope Nikon should warrant any scope problems but that is not going to help you in 3 weeks...

cayugad

I would suggest a couple things. Pull the scope and if this is a two piece base system, switch them back to front, front to back and then remount the scope. Sometimes this will fix the problem, sometimes it will not.

It seems funny that if you took it to bore sight it, the person could have even come close to saying it was bore sighted. All bore sighting does is put you on paper at 25 yards I was told.

Otherwise I would doubt the scope. But a Nikon Omega is a great scope. I really do not think the scope would be bad, but you never know.

cayugad

You might have to have the scope shimmed. A gun smith can do this for you.

flounder33

Good advice by Cayugad as usual. Getting it bore sighted would do nothing to change the fact that you are running out of adjustment on your scope. Shimming seems the most likely solution but if you still have the bases you used before you may want to try them. I have always managed to get them on paper without having somebody lazer boresight them.
Art

UncleNorby

First off, if the scope is good and the rings and mounts are solid, a properly boresighted gun will not hit 18" low at 50 yds. A few inches either way is what you should see.

All boresighting does is get the crosshairs adjusted to where the bore is pointing. You should not see a big difference in one boresight to another. Boresighting will not fix anything if you are out of vertical adjustment.

I suspect something wrong in the mounting system or the scope. I'd tear it down, degrease all threads and screws, re-mount everything with loc-tite (blue) and get it bore sighted again. If the scope has to be cranked toward the far end of its vertical adjustment to bore sight, I'd say the problem is in the mounting system. As suggested above, sometimes reversing mounts and/or rings if possible will fix this. If that does not work, I have to wonder about the scope.

Semisane

I don't know if you're paying to get it boresighted MD DEERHUNTER. But if you are you should save your cash. Just pull the breech plug, rest the gun in a cardboard box with "V" notches cut in the top to hold the gun, and sight through the barrel at a spot about 25 yards away (like a peep sight). Adjust the scope so the crosshairs match the view through the barrel and you'll be as close as a boresight job.

sabotloader

cayugad

Folks, as I read his description, he has had this same problem in the past, maybe even more than once - hence he changed mounts and rings to see if that would help/fix the problem. Which it does not seem as it did. It really sounds like a scope problem - at least from here in Idaho - that is my first thought.

Or have I read the description wrong....

Even then it still could me the mounting system

HEAD0001

You have a problem somewhere. So you need to find where it is at.

To check the scope, put it on a rifle that you know is good. For instance mount it on a 22 rifle that has a scope. I would check the scope first.

What bases are you using?? You did not say. Are they short or long bases?? The shorter the base, the more critical. Also the height of the ring can also be critical. How high are the rings?? How far off the barrel is the bell of the scope?? And how large is the scope bell??

After checking the scope, then the mounts, you have the barrel to check next.

Putting a shim on a scope or base is like putting a band-aid on a cut that needs stitches. A properly mounted scope on a good barrel does not need to be shimmed. Fix the problem, don't put a band-aid on it. It is OK to shim to get you through the season but fix it properly after the season is over. Or expect the problem to reoccur.

You may not like it but it takes time and work to find your problem. So you better get started. Tom.

Semisane

Sometimes relocating the scope a half inch or so forward or rearward in the rings will solve a problem like that. Also, cranking the rings down too tight can cause a problem. Taking it off and carefully remounting it may do the trick.

I always center the elevation and windage adjustments before mounting a scope. If it's a gun with a removable breech plug, I mount the scope with the rings very loose, then position the scope and tighten the rings while checking the view through the bore to get it as close to center as I can before using the scope's adjustments.