front sight calculations

[ken stiles, 0526V]

i had work done on my musket and the dove tailed front sight had to be removed and replaced.

what are the calculations for moving the front blade in order to move the point of impact 1-inch at 50 yards?

the distance between the rear of the front sight blade and the rear sight notch is 23 5/8 inches.

is there a table which lays this out?

thanks much

[pastore]

Ken

The formula for moving the sight is sight radius divided by the range measured in inches. You will of course move the front sight in the opposite direction from the way you wish to move point of impact. The formula will be for a one inch correction.

[Phillip Kearny]

Ken,
SDM Fabricating website supports a sight correction calculator. Just note (3) distance fired, sight radius, and amount od error.
Phil

[Lou Lou Lou]

to move point of impact one inch, adjust sight 0.01325 inches

[R. McAuley 3014V]

http://i267.photobucket.com/albums/ii305/rmac1023/FrontSightElevationCorrectionChart_zps3bb38be5.jpg

[pastore]

to move point of impact one inch, adjust sight 0.01325 inches

Actually, that would be for a two inch correction. A one inch correction would require moving the sight .0065 inches.

[Lou Lou Lou]

Using 1800 inches for 50 yards, I still get 0.1319 inches
Using 3600 inches for 100 yards I get 0.00659 inches.

Richards chart is for 100 yards.

[R. McAuley 3014V]

Yeah Lou, that's what the chart may indicate, but these numbers just get you in the neighbourhood. I sight at the bottom of my rear sight vee for 50 yards, and at the top of the vee for 100 yards, and the depth of the vee (standard M1855 Rifle) is no more than 9/100ths of an inch (0.009-in). Don't know about you but my eye's don't split hairs anymore, and even back in the day before I began wearing glasses to shoot (1989), I don't ever recall worrying about moving my sights this closely. I simply looked at where my group printed on paper relative to the bull's-eye, then adjusted my point of aim to compensate.

[Muley Gil]

Y'all use the sights!!!???

Dadgum, I'll have to try that at the next skirmish!!!

[ballac]

This is the formula that I use.

X=AB/K

X=Distance to move the sight
A=Distance from back sight to front sight.
B=Deviation from point of aim
K=Distance to target in inches

[Robt. Propst]

Tried it from Phil's posting. Great. www.sdmfabricating.com/sightcalc.html

just have to know error in inches, sight radius in inches, distance to target in inches, and you get your correction.

Thanks, Phil. Bob