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montana_charlie
07-24-2006, 02:45 PM
I got one of those Pedersoli Soule sights that I was advertising for, and mounted it on my Sharps.
After dinking with the spring to get it positioned (fore and aft) the way I wanted, I put the gun down to go do 'outside stuff'.
Later that evening, I was considering methods of checking it to see if it was plumb (side to side) with the barrel, receiver, and front sight.

Too lazy to go out to the shop to pad a vise and select a level which would be easiest to hold against the side of the staff, I sat at my reloading bench...just thinking about it.
An idea came to me as I glanced at a cheap plastic 'bullseye level' laying in the top of my in-the-house toolbox.
I usually use it for things like when shimming countertops to get them level front-to-back and side-to-side, without turning the level to check both directions.

I laid my Sharps on a padded table with the level placed on the right-side flat of the barrel. I shimmed under the lever pivot to 'roll' the gun until the level indicated that the barrel flat was square with the universe.

I then placed the level on the side of the receiver, and found that it was also lying perfectly 'flat'.

After those two checks, it was a simple matter to balance the little round flat-bottomed case on the side of the staff to see if it agreed with the rest of the gun.

In my case, it did...so no sight base shim needed (unless I decide (later) to 'lean it to the left' to compensate for bullet precession).

The little plastic level is probably worth about seventy-five cents at the hardware store, and is useful for many things...not just tang sights.
CM

mazo kid
07-26-2006, 05:14 PM
That's a good way to check for level that I haven't tried yet. I suspend a weight tied to a colored string for visibility. Place your rifle in a holder, check for level as you do. Then run your aperture up to the top, sight thru to center on the string. Run aperture down and check again. Any out of level will show up as being off the string when sighted. Emery

Larry Gibson
07-26-2006, 06:36 PM
I got one of those Pedersoli Soule sights that I was advertising for, and mounted it on my Sharps.
After dinking with the spring to get it positioned (fore and aft) the way I wanted, I put the gun down to go do 'outside stuff'.
Later that evening, I was considering methods of checking it to see if it was plumb (side to side) with the barrel, receiver, and front sight.

Too lazy to go out to the shop to pad a vise and select a level which would be easiest to hold against the side of the staff, I sat at my reloading bench...just thinking about it.
An idea came to me as I glanced at a cheap plastic 'bullseye level' laying in the top of my in-the-house toolbox.
I usually use it for things like when shimming countertops to get them level front-to-back and side-to-side, without turning the level to check both directions.

I laid my Sharps on a padded table with the level placed on the right-side flat of the barrel. I shimmed under the lever pivot to 'roll' the gun until the level indicated that the barrel flat was square with the universe.

I then placed the level on the side of the receiver, and found that it was also lying perfectly 'flat'.

After those two checks, it was a simple matter to balance the little round flat-bottomed case on the side of the staff to see if it agreed with the rest of the gun.

In my case, it did...so no sight base shim needed (unless I decide (later) to 'lean it to the left' to compensate for bullet precession).

The little plastic level is probably worth about seventy-five cents at the hardware store, and is useful for many things...not just tang sights.
CM

Doing what you did sometimes gets the job done and sometimes not. Problem is for long range shooting the sight movements are large and a tudge of cant has a large effect on bullet impact down range. The method I use is to put a long, tall target (60-70") up at 100 yards with the aiming point at the bottom. I shoot a group so impact is on the aiming point, 3 or 5 shots depending on the accuracy. Then 50 to 60 MOA is added to the sight and another like group is fired. It helps if the front sight has a level or if not keep the rifle as straight as you can when shooting. Of course shooting is from the bench or a solid prone with cross sticks.

The center of each shot group is marked. A long string with a weight on the bottom (plumb) is lined up with the center of the bottom group. The string should be long enough that it either goes through the center of the top group or to one side. If through the center the rear sight is "plumb". If the string is to the left then the top of the rear sight must be moved to the right. Conversely if the string is to the right of the center of the top group the top of the sight must be moved left. This is the only way I know of plumbing the rear sight for sure. BTW; it is also the best way to "square" the cross hair reticle of an adjustable target, varmint or sniper scope with the bore for long range shooting.

Larry Gibson