Scope Mounting Issue Advice needed

[PeteG]

I'm in need of some advice here.
I am trying out some Warne scope mounts for the first time on my Win mod 70.

So in a nutshell, a month or so back i took my 300wm out to check the zero in the hopes of making sure it was on target. i have been doing a bunch of travelling with the rifle in a padded gun case.
I was getting some pretty random impact on the target, all over the place with no consistency. First i thought it was me, so i packed away all the gear and went out a few days later to try again. Same thing happened.
I checked the barrel, seems clean as normal.
Decided to take the scope off and try the open sights.
Try the open sights and i end up with holes just about touching. a little off zero, so i make the adjustments and get the open sights on target at 100m.
I guess from this that i either have a scope issue or a mounting issue.

I get my hands on a new set of Warne mounts and rings.
Fit these to the rifle, first thing i noted was that i nearly ran out of vertical adjustment bore sighting the scope.
Second thing was to use the magnification and zoom in on a target, but i could not turn the magnification ring.
As i loosen the top screws on the back ring, i can turn the magnification ring.

First question is what and why is this happening?
I guess this means the mounts and/or the rings are not aligned? I have not had this happen before.

Second question is what can i do about this?
I could send them back to the gun shop but they do not have any more in stock for me to swap with. So i would have to try order and ship from outside Zambia.
I am tempted to do this in any case as i wanted to mount another scope in warne mounts and rings on another rifle.
Both scopes are Leupolds.

Here's the kicker... Resident hunting in Zambia has been closed for 2 years, so this has not been an issue the last 2 months, hunting options are few and far between and @spike.t wont let me use his sable as test targets to sight in my rifles anyway.
Yesterday they decided to open hunting, so i have a little more urgency to get this sorted out!
I could use a different rifle, but she's my favourite!

 

[Anthony George]

Which mounts and rings?

 

[Anthony George]

Love the Win M70 by the way

With all my magnums I lecture and torque the bases to the action, and loctite the scope to the rings
Then only torque the scope ring screws down
This will stop any movement of the scope in the rings or movement of bases etc

 

[Von S.]

Hummmmm,

With the technical advancements in machining operation these days it's about impossible to get a set of bases for a 70 that need shimming or cutting like the old days.

Did you say that at one time it was on? If so have you checked all the mounting screws? If so get another scope and try it, but chances are the one that's on there now is buggered up.

Good luck.

 

[PeteG]

Which mounts and rings?

The mounts are the series made for the mod 70. M902/924M on the packaging.
Fixed 1"rings

 

[PeteG]

Hummmmm,

With the technical advancements in machining operation these days it's about impossible to get a set of bases for a 70 that need shimming or cutting like the old days.

Did you say that at one time it was on? If so have you checked all the mounting screws? If so get another scope and try it, but chances are the one that's on there now is buggered up.

Good luck.

Thats pretty much my thinking, I had doubts that the machining process would be so far out... but it certainly is a possibility.

The previous mounts and rings were different, with the same scope and had no issues up until recently.

I decided to change the mounts as it is cheaper to do than replace scopes... and that is mainly because i'm a dumbass and forgot about the spare scope that had been packed away!!!

 

[Von S.]

Pete,

Was it OK with these new rings and bases and then the difficulty started months later

 

[PeteG]

Pete,

Was it OK with these new rings and bases and then the difficulty started months later

No, the difficulty was immediately as was installing the new scope.
As soon as i noticed that tightening the rings was doing something to the scope that stopped me being able to adjust the magnification, i stopped any further tightening of the screws.
I have not shot the rifle either with this new setup.

 

[Von S.]

Oh no!

This is bad. It could be that you might have the wrong bases for your rifle, meaning that one base could be higher than the other and as you tightened down the screws it inadvertently bent the tube and wrecked the internals.

I assume that you do not have alignment points that you use to make sure that everything is aligned up before you throw the scope in the rings?

Pete, once a scope is bent it is doubtful that it will straighten out and be reliable ever again..

If you have machinist ruler, take the scope off and sit the ruler on edge inside the bottom of both rings at the same time and if it teeter totters you have the wrong bases...or rings also.

 

[PeteG]

I will double check on the bases.
https://warnescopemounts.com/product/m902924m/
These are them.

On the bases i took off, the rear is higher than the front so i didnt even think twice when i installed the new ones.

Everything lines up with the scope in the rings, its only the final torquing that seems to screw me about, no pun intended.

I will check with a rule and see if there is any difference.

 

[Ridgewalker]

I lap my rings before installing a scope. This will let you know how well aligned they are. It also removes any burrs from the machining process. You’d think they would vibratory mill the rings to eliminate burrs, but it’s an additional step that takes time.

 

[Hogpatrol]

What screws are on the zoom ring that are supposed to be loosened up? Never heard of a Leupold or any other scope for that matter, where any lens screws should be touched. Your rear ring isn't touching the zoom ring and binding it, is it?
I looked at the bases and the rear one is thicker. Other base sets for other brand rifle/actions are similar. The rear of the actions are lower, thus a thicker rear base is needed. I don't have any 70s, so just guessing they are like that. Back on the scope, what was the reason for the switch if it was ok before?

 

[PeteG]

I lap my rings before installing a scope. This will let you know how well aligned they are. It also removes any burrs from the machining process. You’d think they would vibratory mill the rings to eliminate burrs, but it’s an additional step that takes time.

You’d think so, that step should be part and parcel of the manufacturing process.

 

[PeteG]

What screws are on the zoom ring that are supposed to be loosened up? Never heard of a Leupold or any other scope for that matter, where any lens screws should be touched. Your rear ring isn't touching the zoom ring and binding it, is it?
I looked at the bases and the rear one is thicker. Other base sets for other brand rifle/actions are similar. The rear of the actions are lower, thus a thicker rear base is needed. I don't have any 70s, so just guessing they are like that. Back on the scope, what was the reason for the switch if it was ok before?

Hi, the screws I’m talking about are on the rear mounting ring. I’m not fiddling with the scope at all.
I’ve moved the scope forward and back so I doubt the rings are binding on the scope magnification ring.

You’re right on the rear base, it is thicker than the front to level out the difference on the action.

 

[Hogpatrol]

What is the Warne ring height? Thickness of the Warne bases? Both of these compared to the old setup? There's a possibility of the rings being too high or low and causing the elevation turret running out of adjustment. Also, I would exercise the turrets, all the way one way, then back and then find mechanical center (use a mirror).

Then boresight it.

 

[Shootist43]

I recently purchased a set of Warne rings and bases for a Winchester Mod 70. It seems to me that there were two options available but only one would be correct. I don't recall what made the difference. You might try emailing Warne and discuss your "problem" with them. I'm willing to bet the "fix" is rather simple. You might try going to Warne's online catalog to select / determine which pair /set of rings and bases are made for your rifle. You may just have the wrong ones.

 

[PeteG]

What is the Warne ring height? Thickness of the Warne bases? Both of these compared to the old setup? There's a possibility of the rings being too high or low and causing the elevation turret running out of adjustment. Also, I would exercise the turrets, all the way one way, then back and then find mechanical center (use a mirror).

Then boresight it.

I will check the heights and compare them.
Will also have a look at the video and try that.

 

[PeteG]

I recently purchased a set of Warne rings and bases for a Winchester Mod 70. It seems to me that there were two options available but only one would be correct. I don't recall what made the difference. You might try emailing Warne and discuss your "problem" with them. I'm willing to bet the "fix" is rather simple. You might try going to Warne's online catalog to select / determine which pair /set of rings and bases are made for your rifle. You may just have the wrong ones.

Went back on their website as you said.
i have in hand the Rings as Part # 201M and the bases as M902/924M.
As per their Ring and Base selector on their website, i have the correct bases and rings.

I am beginning to think that either one of the rings or a half is badly made/reject.

 

[Shootist43]

If you have a caliper, measure the height of the respective bases and determine if they are as they should be. Obviously there is something wrong, the most likely culprit is one of the bases . One final question, do you have the bases mounted in the correct location i.e. front and rear?

 

[PeteG]

If you have a caliper, measure the height of the respective bases and determine if they are as they should be. Obviously there is something wrong, the most likely culprit is one of the bases . One final question, do you have the bases mounted in the correct location i.e. front and rear?

I dont have a caliper here at home, but i have placed the old bases and the warne bases one in front of each other on the rifle. The old bases are both slightly higher than the new warne bases.

The difference in height between the old rear base and the new rear base is slightly more than the difference between the old and new front base.
That would explain the large vertical adjustment.