Model 7 308 sighting in issue

erik1972 · May 6, 2013

Hello all,

I have run into an issue while trying to sight in my Model 7 in 308 this weekend. This setup I have on mutlipe Model 7's but this scope is adjusted now and still 10" high. Its a Model 7 in 308 with Gentry Custom rings and bases and a Zeiss Diavari 3x9x36 scope. At 100 yards I am centered L to R fine but 10-11" high and I have the scope dialed down all the way.

I should say, this is the first time using Gentry rings and bases. On my bore sighter I can see the crosshairs moving in the scope so I know the scope is working correctly. I have never had to shim before but always used Leupold rings and bases.

Should I try new rings and bases first or what? Thoughts?

Thanks, Erik

RELH · May 6, 2013

You have two choices. Shim the front mount or switch to the Leupold bases and rings and see if that corrects the problem.

I would switch the rings and bases first if it was my rifle.

RELH

chessidawg · May 7, 2013

have tried to pull up on youre ajustment ring and turn it back to get more clicks , i had to on my ziess scope

erik1972 · May 7, 2013

I spent some time last night tearing everything down and remounting the scope. The gun came with these Gentry rings and its the first time I have used them. They look like a quality piece except for some of the machining on the bases seems a little crooked/off.

Previous owner states that this gun was a great shooting gun. Maybe thats why he sold it, right!!

Anyways, I put everything back together and reboresighted it in. All I have is a magnetic bore sighter that sits on the end of the barrel, made by Bushnell. I was able to center everything up this time and I do still have some downward adjustment left on the scope. I wont be able to shoot until saturday morning so we will see.

I was not aware of being able to pull up the adjustment pieces on the scope to get more adjustment. We will see what happens saturday.

Thanks, Erik

AZBuckSnort · May 8, 2013

Did you mechanically center the reticle adjustments?

erik1972 · May 9, 2013

I am not sure what you mean by mechanically centered the cross hairs? I remounted everything and bore sighted it back in by turning the windage and elevation adjustments until the crosshairs were centered on the bore sighter. This Zeiss scope does not give me the option of pulling up on the adjusters and dialing them to zero. I will know saturday morning morning if this works. If not I have some Leupold rings and bases to throw on too.

Thanks, Erik

AZBuckSnort · May 9, 2013

LAST EDITED ON May-09-13 AT 06:57PM (MST)[p]Count the number of clicks or turns of adjustment and then dial back to the center/middle for both windage and elevation. Rifle scopes don't necessarily leave the factory with a centered reticle, ditto if you purchased a preowned scope.

waspocrew · May 10, 2013

>LAST EDITED ON May-09-13
>AT 06:57?PM (MST)
>
>Count the number of clicks or
>turns of adjustment and then
>dial back to the center/middle
>for both windage and elevation.
>Rifle scopes don't necessarily leave
>the factory with a centered
>reticle, ditto if you purchased
>a preowned scope.

I imagine that is most likely the issue... You'll want to do that and then bore sight again- that way you will know that your scope has plenty of adjustment.

erik1972 · May 10, 2013

Thanks for all the replies, tomorrow morning I will see if remounting the scope fixed the problem or not. Finding center adjustment on the scope before bore sighting makes some sense, but it will not get me any more adjustment on the reticles at all.

The scope is going to line up where it does when it is mounted on the rifle. When you add the bore sighter to the barrel, the crosshairs will be where ever they fall within the scope. Whether the cross hairs are centered prior to bore sighting or not will really not give me any more adjustment, If the elevation was centered or low like it is currently, I would have to adjust accordingly anyways. Correct?

Say I did not centered the reticles before I mounted the scope and after remounting the scope it fixed the problem. Then it would be shooting extremely low since elevation adjustment was completely bottomed out. All I have to do is raise the adjustment.

Thanks, Erik

erik1972 · May 11, 2013

Well, another day at the range with my 308 and just wasted some more ammo on a rifle I cant get to shoot. This time I went with the scope reticles centered in the middle of there adjustments on the scope and the rifle bore sighted in as good as can be.

Everything still shot high even as I started to move the elevation adjustment down the shots were the same or higher. I did not want to waste anymore ammo with this setup so I tear it all apart again and mount a Leupold 1 piece base and Medium rings. I centered the adjustments knobs again and bore site again. I can see the reticles moving correctly when I bore site the scope in. At 50 yards and the first four shots were left 2 inches and high 4-5" but in a good 1" group. So I was starting to feel good.

So I decided to adjust the scope down and move out to 100 yards and see. I adjusted the reticle down 8 clicks so I would hopefully be 2" high at 100 yards. The first shot was high off the paper which would mean maybe 10" high. I adjusted the scope down 12 clicks for 3" and the scope shot exactly where the first shot at 100 yards went. Absolutely no movement down at all. I moved the reticles down one more time 2" more and same shot still 8-9" high. This only left me with maybe 10-12 clicks left.

I am at a complete loss! Its got to be the scope, since I have ruled out 2 different brands of rings and bases. Looks like I will be calling Zeiss on monday and see what they have to say.

Thanks, Erik

RELH · May 11, 2013

You are doing some things wrong. Most scopes will move 1/4 inch at 100 yards for each click. When you adjusted at 50 yards, you should have adjusted 2 clicks per 1/4 in movement. Or 8 clicks per one inch of movement.

Some centerfire scopes will move 1/2 inch per click, but the majority is 1/4 inch per click. Before you do any calling, have a friend, that is good at bench shooting, try your rig out and see if he can find the problem.

RELH

erik1972 · May 12, 2013

The problem has been found! After some conversation with one of the most informative hunter/reloader/bench shooter I know. We have come to a conclusion on the issue. He has multiple Zeiss scopes and Leupolds for that matter. And he confirmed my suspicion from some shooting book he has. And my bore sighter confirmed it as well.

Compared to a Leupold, the Zeiss reticles adjust in the opposite direction as any Leupold scope does. The reticle on a Leupold says U for up so if your shooting low you raise the reticle up. My Zeiss scope adjusts the opposite direction, his literature says the German way is to follow the bullet on the target. Also goes for the magnification, the Zeiss actually turns the opposite direction as the Leupold.

This is fine for me, except for the fact the instructions that came with the scope says something different. It says if shoot high move the reticle in the D position which is clockwise. This actually lowers the crosshairs on the Zeiss and raises the crosshairs on the Leupold.

Back to the range!