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MOA on Diopter Sites

Posted: Mon Nov 06, 2017 9:58 pm
by Stephen1974
Hi,

Recently bought a set of Air Arms Diopter CZ 6213147R sights and was wondering if anyone knows what the Minute of Angle is on them. I've seen various claims of 2mm 5mm and 8mm, have had no joy from air arms either. I'm hoping some MPR or s200 shooters will know.

Re: MOA on Diopter Sites

Posted: Tue Nov 07, 2017 9:35 am
by TenMetrePeter
The angle will depend on the sight spacing and the mm on target will depend on the range. I never knew manufacturers ratings actually play out in practice.

If you shoot at say fixed 10 metres, set up the rifle in a fixture if you have one or aim at a target from a sandbag. Shoot a group. turn the sights down 4 full revolutions (count the clicks). Shoot another group. measure the shift. Then divide by the number of clicks. That will give mm per click at 10 m.
The minute you move the sights forward to change eye relief your mm per click will change.

If you want a formula for adjustment for different ranges like in field target, there isnt one. Trial and error will do it

I upgraded to match quality Centra sights to support a MEC Swap and their numbers are meaningless too.

Re: MOA on Diopter Sites

Posted: Tue Nov 07, 2017 7:33 pm
by Stephen1974
Unfortunately I dont have the option to do that.

Re: MOA on Diopter Sites

Posted: Wed Nov 08, 2017 12:48 am
by TenMetrePeter
Stephen1974 wrote:Unfortunately I dont have the option to do that.

OK if you don't have a bench to shoot off, you will at some stage need to sight-in the sights on your 10M range. Shoot a group of pellets aiming at the target card aiming mark (the Black). Measure the horizontal and vertical distance that the centre of the group is off target. Then as you wind in the adjusters count the clicks, write them down, and when your group centre is on target, divide the distance you were out by the number of clicks to correct it. You should then have roughly the same mm per click in vertical and horizontal directions, for your set-up and nobody else's.
All you need is the rifle and a target card. Manufacturers quoted shift per click is almost useless for diopters for the reasons I gave earlier.

Re: MOA on Diopter Sites

Posted: Mon Nov 13, 2017 7:04 pm
by TenMetrePeter
In case you are still reading this you might like to look at the first 4 minutes of this
https://youtu.be/KqAogqMzKoo
to fettle the sight in. They are not well made.