Zeroing a ladder sight

[Watcher]

I'm having my TR re-barrelled and having a Fulton's ladder sight fitted. Has anyone any experience of zeroing a ladder foresight?

[rox]

I'm having my TR re-barrelled and having a Fulton's ladder sight fitted. Has anyone any experience of zeroing a ladder foresight?

It depends a little on the foresight diameter and the height at which the rear-sight gives you a comfortable sight-line.

I start as follows - note that some sights are marked as having 5' intervals, and others as 6' intervals, despite having exactly the same pitch.

Start with the lowest foresight position for 1000 yards. You will use the following positions for the various distances, where zero = lowest, +1 is the next one up etc:

0 = 1000
+1 = 900
+4 = 600
+5 = 500
+6 = 300

(hopefully this is correct - it is from memory).

You can zero at any particular distance as long as the foresight is in the correct position. Once you have the zero by adjusting the rearsight you should find that the rearsight position will be within a couple of minutes of this at all the other distances (the majority of the adjustment done by the foresight). The important thing is to make sure you are happy with the head position. If necessary you can raise the sight-line from the above by adding one or more units to the foresight position and raising the rearsight accordingly (e.g. move the foresight up 2 notches for all distances, and add 10 minutes to the rearsight).

Once you have established a set of front and rear settings remember that they are independent - consider them as being in different units. Never ever add front and rear elevations to make a 'total'.

..

[Dougan]

If it's the same as mine, then each 'notch' is 5 MOA - Assuming you're going to shoot the full range between 200 and 1000, then you need to zero it at 200 with the front sight set high enough that it can be brought down 7 notches (35 mins of elevation for 1000) without the sight touching the barrel.

[Watcher]

Thanks gents.