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Best value in 20moa base?/ does a shim exist for use on any bases?

Shawnba67

I seem to be in need of a 20moa base for my scope. I have limited funds so I don't need bells whistles or the such just solid mounting. Any recommendations?

The shim question , I have a really nice one piece DNZ game reaper scope mount on my rifle now if a long tapered shim exists I might be able to utilize that and keep my nice DNz mount also.
Please don't tell me to sell it.the hits hurt to much I couldn't sell a $20 bill for $17 if you gave me all day to do it.
 
If you've got more time than money, which is how I spent my first 2.5 decades, you should be able to raise the rear with epoxy if you know how do do bedding. Generally I wouldn't recommend this but I believe you should be able to get good results if you do it right. You will need longer screws and may have to relieve the holes of your current rail. take your time and keep tolerances tight. If you need help calculating the amount to lift it let me know (use tan .33 deg x distance between front pivot point and shim. Works out to about .023" in 4"). of course bed the front and the rear.

Bedding a rail is sometimes necessary even for a rail in the as designed configuration so adding .023 to the back shouldn't hurt. The screw head bases will be off a bit but not enough to matter.

--Jerry
 
Shawnba67 said:
I seem to be in need of a 20moa base for my scope. I have limited funds so I don't need bells whistles or the such just solid mounting. Any recommendations?

The shim question , I have a really nice one piece DNZ game reaper scope mount on my rifle now if a long tapered shim exists I might be able to utilize that and keep my nice DNz mount also.
Please don't tell me to sell it.the hits hurt to much I couldn't sell a $20 bill for $17 if you gave me all day to do it.
Click to expand...
What kind of gun ?
 
Shawnba67 said:
I seem to be in need of a 20moa base for my scope. I have limited funds so I don't need bells whistles or the such just solid mounting. Any recommendations?

The shim question , I have a really nice one piece DNZ game reaper scope mount on my rifle now if a long tapered shim exists I might be able to utilize that and keep my nice DNz mount also.
Please don't tell me to sell it.the hits hurt to much I couldn't sell a $20 bill for $17 if you gave me all day to do it.
Click to expand...

You could shim your base then bed it to the action. I like to shim the scope rings and bed them. You calculate the shim thickness according to the center-to-center distance of your scope rings.

The thickness calculation for a 20 MOA base shim is:
0.0055" × ring spacing in inches (center to center)

So if your rings were spaced exactly 4 inches apart, your shim would go under the scope in the rear ring and be 0.022" thick. Build a shim out of tightly compressed aluminum foil, then bed the scope in with JB Weld. Of course rings would have to be lapped and rings lightly tightened to no more than 5 in-lbs when setting the bedding.

The same calculation could be used to shim and bed the base, you would just have to be sure that the shim is place directly under where the rear ring is mounted to the base.

I personally like to mount my scope, carefully bore sight, then calculate exactly what size shim I will need to be at optical zero when shooting 600 yards. This is usually much less than 20 MOA. Be sure to account for how much elevation travel used from optical zero so you can figure it into the 600 yard adjustment. So let's say it's 13 MOA with 4 inch spaced rings for example. Being that I know I need 0.0055 per inch thickness for a 20 MOA compensation, I calculate 13 MOA compensation shim like this:

13(moa) ÷ 20(moa) = 0.65

0.65 x 0.0055 = 0.003575 = Round to .0036

0.0036 x 4 = 0.0144" shim thickness
 
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Thanks very much for the formula. I think I might try and make a shim to go under my base. With the math to guide it seems more doable now.
 
Shawnba67 said:
Thanks very much for the formula. I think I might try and make a shim to go under my base. With the math to guide it seems more doable now.
Click to expand...

I recommend bedding with JB Weld. Bed the shim into the bedding that will remain bonded to the base. Be sure to apply plenty of release agent to the action, mounting screws, and screw holes in the base. Be careful not to get the bedding agent in the screw holes on the action. The shim does not have to be very large as the bedding will act as the shim perfectly formed to the action and base once cured.
 
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Not sure what it is for but Nightforce makes a standard duty pic rail for 50.00+ on Amazon. Free shipping. Should be a decent mount for non Magnum guns.
 
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