Scope Problem

[Bullard4075]

I have mounted a shotgun scope ( the why is a longer story- more eye relief) on my Savage 110, 300 Win Mag. As this scope is an
intermediate eye relief scope I had to "make up" a scope mount for it.
The scope is a new B-Square shotgun scope. Everything is tight.
I cut a one piece base in two for the front part and used the rear half of a two piece base for the rear.
My question is, could be this mount flexing enough to cause four to five inch groups at 100 yards ?
Is a shotgun scope tough enough for a 300 Win Mag?
This gun (and or me) with the same loads is usually a 1 1/2 inch gun.
Sighting in is very trying as adjusting is a jump all over the target kind of thing and I have no way of knowing
if the mount is flexing or the scope is not taking the "clicks" properly.
While writing this it occurred to me I might put an additional ring on the forward base to stiffen it more.
Picture follows.
Your thoughts.

[harry]

It sure looks like you have a mis match of bases, it looks like the front base is to low compared to the rear base and the front ring has pulled the extended part of the front base up. If you look at the picture the middle of the bolt, the gap from the top of the bolt to the bottom of the base is greater than the gap at the front of the bolt by alot.
WY2000

[BigSky56]

I believe your front mount has tension on it and is flexing put a standard front mount on and get a set of millet angle loc rings one being a extension ring should solve the problem your having. danny

[M. M. Wright]

Check for parallax.

[kimwcook]

I believe, as stated already, that your front mount is flexing. Need to get that replaced, but with the scope your using I don't think you have enough tube to do it right.

[Chuck 100 yd]

" Check for parallax."
Most shotgun scopes are parallax corrected for 50yd. and can be way off at longer ranges.
I have found scopes so bad they wont stay on paper at 100.

[AJMD429]

What about using a long one-piece mount, scalloping the right side out enough to access the chamber area if need be. There are commercial mounts made that way, though I don't know if they're for that particular firearm.

[Pete44ru]

If it was my rifle/situation, I would either:

1) (least expensive) Buy/install a one-piece Leupold STD base for the rifle, then measure the span needed to reach the scope used & buy one or both (ft/rr) extension ring(s) so I could use that scope.

or

2) Buy/install a one-piece XS Scout rail, and use either a 2x pistol scope or a "Scout" scope from Burris or Leupold.

.

[bgmkithaca]

I have not had parallax problems at the range mentioned with any quality shotgun scope, has not been much of a factor
until 200 yards and beyond. As for strength I have used them on .458 magums and they take the beating better than I do.
The key is use good scopes. As for the problem listed it looks almost certainly to be a mounting problem- both mis-match and the probability of base springing and vibration. Good Luck-something will work for you.