Need Advice on shimming a scope

Lay a straight-edge length-ways on top of the scope base front to back. Is there a gap under the straight-edge at any point, especially towards where the rear scope ring sits? If so, the base has been bent, in order to sit on top of the rear bridge & even if you get a new base, you're still going to have to shim the rear base to have it on the same plane as the top of the front base.

To bring the elevation up 5" will require 20 clicks UP [if your scope moves 1/4" per click, perhaps only 10 if the scope is a lower power scope with 1/2" click per adjustment, more if it has 1/8" adjustment per click. If it's European, it could be a number of things. Usually, the amount of adjustment per click is written on the adjustment screw.

click.jpg

A lot of people like their POI to be ~3" above the bullseye at 100 yds., in order to maximise their Maximum Point Blank Range [the distance within that you do not have to remember where to hold in order to obtain a clean kill].

Just for $#!T$ & giggles, take the cap off the elevation turret & screw the screw all the way one way until the stop. Now screw it back all of the other way. Now, proceeding slowly, count the # of clicks from stop to stop. Now dial the adjustment screw half way between the stops. Remove the bolt & set the rifle on top of a steady rest [a sandbag works if you do not have a proper rest]. Now bore sight the rifle to a point at least 25 yds away. Counting the clicks, screw the adjustment screw so the crosshair is super-imposed directly on the chosen target.

What are the results?

Usually, if the POI is ~dead on at 25 yds., it will be ~3" high @ 100yds., unless it is either a hot varmint calibre or an old-time boomer cartridge.

MPBR.jpg
 
Sounds like a +20 MOA base or rings on backwards, if you NEED 5 MOA (5 inches @100yd) shim then you want at least 10 MOA to have some adjustment for different ammo. anywhere from +20 to +40 MOA might be appropriate depending on the scope's range of adjustment. flipping a 20 MOA base or rings the opposite direction gives you a 40 MOA change.
 
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I had to shim the scope on a Wickliff in 22-250. I set the turret to zero (dead centre of travel) then put my bore fighter in it snd shimmed the scope with paper shims (iirc) until the crosshairs were close to centre. This gives me the maximum adjustment up and down. Didnt take much to dial it in.
 
I think the OP finally figured out that he needed to adjust the elevation turret in the up direction to raise the bullet trajectory.
27 posts to get to what I said in post #2.

CGN contributors seem to have an unlimited ability to not read, nor understand what the OP asks / posts and we get these long threads that are COMPLETELY off course.
 
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