doublegunshop.com - home Forums General Discussion German & Austrian Sporting Guns @ doublegunshop.com Windage adjustment query

This .300 Savage Model 45 is fitted with a Geco branded scope. According to the Internet these post war scopes with this style of elevation turret cap was made for various German retailers by Schmidt and Bender in their early days.

windage adjustments are in the rear mount by 2 opposing screws. The rings are 3.375 apart (centre to centre).

At present it is shooting 4.5 inches right at 100 yards.

Do any forum members have any experience in knowing how much in Minutes of Angle a half or full turn by the pushing screw (after slackening off the opposing screw) will shift the MPI?

Parabola,
Unfortunately, having had experience with this type of scope, I can see the type of mounts use do not adjust easily. The easiest solution would be to change to Redfield type or similar mounts with adjustments built into the rear mounts. Failing this, you can resort to filing the dovetails to move the scope in the desired direction. To move the point of impact to the left, move the rear of the scope to the left, or the front of the scope to the right. If necessary, you can move both front and rear of the scope. The rifle was made without having been drilled and tapped for mounting screws and it may have been drilled improperly. It is also possible to move the bases by opening the hole(s) in one or both of them and shimming one side. It is often surprising how little the scope has to be moved to sight it in.
Mike

You can use the screw pitch to determine the feed of the screw per revolution.

Thanks, I will take out the non-pushing opposing screw and measure the screw’s tpi. That should not shift it in the dovetail.

I can then adjust by using the pushing screw.

I have calculated that I only need to move the back ring just over 4 thou left.

I will boresight again but in the end it will come down to Trial and Error.

Parabola,
I can only see one side of the rifle, so your information is better than mine. I still believe there are not "non-pushing" and "pushing" screws in each mount, rather it looks like there is only one "clamping" screw with a "nut" for each mount.
Mike

Steve Earl may produce some rings that can be adapted to your mounts if needed. Here is is website

https://www.steveearleproducts.com/

Der Ami,

The photo is deceptive because taken at an upward angle. There are a pair of opposing screws directly above the clamping screw.

Parabola,
The screws above the "clamping" screws seem to be screws that hold the top half of the rings on to the bottom half, holding the scope in.
Mike

Mike, the upper pair of screws are the screws that hold the top half of the rings down.

One of screws that I am referring to, that move the top half of the rear mount in a lateral dovetail, is just visible in my picture partly hidden by the knurled end of the rear clamping screw.

I was meaning to measure the screw pitch, but didn’t get round to it. The day before I was going to the range I slackened off the left hand screw just over a quarter turn tightened the right hand screw a quarter turn (moving the back ring left) and re-tightened the left hand screw to lock it up.

I had been shooting 4.5 inches right, and I found it was now 2.5 inches left. I reversed the process just on an eighth of a turn.

I then shot this card at 95 yards taking a 6 o’clock aim with the tip of the German No. 4 reticle just touching the bottom of the sqare.

The cluster of three shots almost exactly where I was aiming are my hand loads with 125 grain Sierra .308 Gameking in re-formed .243 PPU brass.

I then fired 3 rounds of fairly ancient (22 February 1961) Winchester 150 grain .300 Savage Silvertip factory loads. There is a pair to the left of my first three shots and a slight stray at 5 o’clock.

That Savage 45 has been used fairly hard, but the barrel remains in good shape and it is remarkably accurate even by modern standards.

"Minute-of-cloaca."

I'd keep that one, sir.

I still can't see the adjustment screws, but I see the resulting group. There is no doubt that it worked, good show.
Mike