how to shim a scope

R

rebs

New member
I want to shoot my 541 22 lr at a 200 yd bench rest match. I was told by others that I need to shim my scope. How do I shim it ?
 
I use brass shim stock from the auto parts store which goes under the base. Some people make shims from soda cans which should work just as well.
 
You really need to maintain ring alignment.Just raising up a ring or base with shim stock will mis align the rings.

You pay a lot of money for precision tolerances inside the scope. You might even have some super glue assemblies.

Tighten up mis aligned rings and you will distort your scope tube.All that precision is gone.IMO,that is root cause of a lot of scope trouble.

IF you have a one piece ,bridge or rail type base,you might make do with a shim under one end. I'd supplement wit some form of bedding compound.
Gently snug the screws,let the bedding set,then finish tightening the screws.

emcon is right,the tapered bases are best.

I have never used them,but I think Burris offers some kind of eccentric sleeved rings.Those might get you through your match.

The tan of 1 deg is approx. .01746. One deg is 60 MOA

So,if you want 20 MOA? Divide by 3. About .0058 . Now,how far apart are your rings? Maybe 4 in on a .22? So we multiply 4 times .0058 would give you
a .023 shim,approx.
That .01746 number is key.For every inch of ring spacing,you need .01746 of shim to get 60 MOA on target. So,(ring spacing,in) times .01746 = shim for 60 MOA (1 deg). If you want 15 MOA,(1/4 deg) divide that number by 4.
You will likely be looking at a 1/64 in or a .016 or .018 or .020 shim.
 
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You have to shim the rear scope rings, for increased elevation.

I used old style 2-bladed razor blades, for shims for my recoilless air rifle rear scope ring; for 100 yard metallic shooting at a cowbell.
 
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Just buy a one piece base with 15 or 20 moa built right in to it. It won't cause any problems with your rings since you aren't shimming the rings at all. Lots of competition rimfire shooters use them. Check it out on rimfirecentral.com
 
They make hims meant to go under bases. If you did same front and back, scope would still be aligned.

Sadly I don't think many people or know how keep a scope aligned or rectilile level.
 
Best shims I ever made were cut from the base of a high-brass shotgun shell. Use a Dremel tool and cut off the rim, then split the brass vertically 180 degrees apart.
 
Never used them, but the ones made to shim have holes that will line up with screws to keep it in place, and not stick out. Also they are the same thickness, so keep it even.
 
They make hims meant to go under bases. If you did same front and back, scope would still be aligned.

Sadly I don't think many people or know how keep a scope aligned or rectilile level.
Click to expand...

Sorry, if he put the same shim under both front and rear bases, how would that help him get more elevation for long range shooting?

In this case, he wants the rear to be higher than the front.

The correct answer is to buy the right base with the extra elevation built in.
 
My question is: does the Rem 541 use screw on or grooved bases? If grooved, it's going to be VERY difficult to find a base with built in elevation. I have seen adapters that would convert grooved to common Weaver so a MOA rail could be used.
 
What's the mid-range height for a .22 rimfire at 200 yards?

I ask because I shot ten inches high at 100 yards to have my '06 right at dead-on at 500 yards. No trouble with scope adjustment; no shimming needed.
 
The brass shim stock from the auto parts store isn't horribly expensive and comes in different thicknesses too.
"...shims from soda cans..." Pop cans(snicker.) are all pretty much the same thickness.
However, before you do anything, shoot your rifle at 200. There are no absolutes in Firearms Land. Like Art says, you may not need to do anything.
Your rifle have a heavy barrel? Mind you, 'Bench Rest Match" means different things to different people.
 
He may not have enough adjustment in his scope to raise it high enough. Dunno.

I do play with nikon spot on, and decide how high I want gun to shot at what distance.
 
200 yards

We shot steel crows at 200 yards at a Nikon shoot one time. Had to zero at 100 yards then used the BDC post for aiming. It was in a semi dug out range with berms on all sides so wind was a non-factor. It was really kind of anticlimactic pulling the trigger on the bull barrel 10/22's and registering a hit every time. Big fun though!

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I shimmed using aluminum cans that I cut. They also sell brass shims at local hardware stores like Ace True Value.


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