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Ever Shim a scope?
Horney toad
Member Posts: 1,769 ✭✭✭✭✭
I have a browning B-78 in 25-06. It came with a 1 piece leupold mount. When sighting in, I adjusted the scope all the way as high as it would go, and it still shot low.
Could I shim this scope to make the front higher? I assume I would place the shim under the front of the mount.
Could I shim this scope to make the front higher? I assume I would place the shim under the front of the mount.
Comments
Have you tried immobilizing the rifle and moving the cross hairs to the point of impact? If you are on paper, it is the quickest way to confirm if you are within the range of adjustment.
edit:
Please don't take offense if this is obvious. I've seen a number of people get frustrated sighting in a rifle only to discover they were adjusting the wrong way.
Brad Steele
Something sticks in my mind that the Browning takes a different mount set up. I used two different two-piece mounts to get the scope level when I was testing one of these. Check either the Brownells catalog or their website to see if they have a list in conjunction with the base and ring manufacturers.
The very first thing you need to do is set the windage and elevation to the middle of the range for each. The next thing to do (after getting the correct bases) is to center the scope on the rifle with the bore. This doesn't mean to use the scope elevation/windage adjustments but to physically center the scope using either the base windage (Leupold) or ring inserts (Burris) plus the inclusion of shims if required. Once the scope is bore sighted correctly, head for the range to do the fine tuning.
I included the following for your reference to shimming:
Bushnell Guide to Shimming Riflescopes
To ensure years of dependable service, we suggest you have your riflescope professionally mounted.
An off-axis optical alignment between the rifles bore and the riflescope may result in scattered groups and poor optical performance, as well as possible internal damage to your riflescope. Shimming may be required to properly align your riflescope to the bore of the rifle. This alignment of the riflescope mount to the bore will reserve the riflescope's internal adjustment for small, fine corrections needed to sight-in. A shim table is included to assist your gunsmith in the proper mounting of your riflescope to the suggested course alignment.
LIT #: 98-0243/04-03
* ELEVATION and WINDAGE adjustment travel should be reserved for fine correction. While normally not
required, major alignments should be made by shimming the mounts and/or bases. Over-adjustment of Elevation and Windage controls may lead to internal damage of your riflescope.
SHIMMING FOR MAJOR ELEVATION ADJUSTMENTS:
Shim Front Base For Additional Down Movement
Shim Rear Base For Additional Up Movement
For Major Windage Adjustments We Suggest Using A Windage Adjustable Mount
For Best Results Use The Lowest Profile Mounts Possible
SHIM TABLE
DISTANCE (Yards) _ SHIM THICKNESS (Inches) _ POINT OF IMPACT (Inches)
25
.001
0.25
50
.001
0.50
100
.001
1.0
200
.001
2.0
25
.002
0.50
50
.002
1.0
100
.002
2.0
200
.002
4.0
25
.003
0.75
50
.003
1.5
100
.003
3.0
200
.003
6.0
25
.004
1.0
50
.004
2.0
100
.004
4.0
200
.004
8.0
25
.005
1.25
50
.005
2.5
100
.005
5.0
200
.005
10.0
Formulas derived from a 3.25" ring spacing. These values may vary.
Best.