Gehmann 22mm Front Iris w/ Horiz. Bar (2.4-4.4mm)
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Gehmann 22mm Front Iris w/ Horiz. Bar (2.4-4.4mm)
I'm brand new at shooting 10m and I'm just learning about the gear for the sport so bear with me if this sounds like a dumb question. I have a FWB 800x that I recently bought which has a 22mm front sight. The glass ring front sight iris that came with it works well for me size-wise but I want to try the type that has the horizontal bar. I checked around but couldn't find any that FWB makes but I did find a 22mm offered by Gehmann (http://www.champchoice.com/store/Main.a ... tem=520A22) on the Champion's Choice website. The description says it's 2.4-4.4mm. I saw references to adjustable front sight iris's on the net but I'm not familiar with them and don't understand how one can be adjustable. First, is the ring and bar mounted on glass or is it simply a metal ring w/bar insert mounted in the front sight (I've seen those kind online). I understand if it's the metal insert kind that you can get different size inserts, but If it's mounted on glass how can you physically adjust it since it would be a fixed size? I haven't seen any rings w/horizontal bars offered in single diameters so I know I'm missing something obvious here. Any help understanding this would be appreciated.
Re: Gehmann 22mm Front Iris w/ Horiz. Bar (2.4-4.4mm)
Thanks much BR. It looks like it changes the thickness of the ring itself which changes the diameter of the inner circle. Not sure how it actually does that but all I need to know is that it does. Appreciate the video. I'm going to order it. Being new at 10m I think it'd be a good thing to have until I can settle on a size that'll work for me. Thanks again.
Gene
Gene
Re: Gehmann 22mm Front Iris w/ Horiz. Bar (2.4-4.4mm)
Gene,
The ring is made up of a series of overlapping metal leaves, just like a camera iris. As you turn the back of unit, the iris opens or closes to vary the aperture. Some irises just change the inner diameter, i.e. the ring gets thicker as the aperture gets smaller, and thinner as it gets larger. Others maintain a constant thickness. You can get iris tunnels that allow you to vary both the inner aperture and the thickness of the ring.
The ring is made up of a series of overlapping metal leaves, just like a camera iris. As you turn the back of unit, the iris opens or closes to vary the aperture. Some irises just change the inner diameter, i.e. the ring gets thicker as the aperture gets smaller, and thinner as it gets larger. Others maintain a constant thickness. You can get iris tunnels that allow you to vary both the inner aperture and the thickness of the ring.
Re: Gehmann 22mm Front Iris w/ Horiz. Bar (2.4-4.4mm)
Gene,
As Tim has already noted, the adjustable aperture works like a a camera lens. Applies to the adjustable front and rear apertures, same principle, different location.
Now, the next mistake that new shooters often make is to use too small of a front aperture. They get themselves thinking that the smaller the white ring around the bull the more precisely they will be able to align the sights. For a number of reasons, the eye does not work that way. You will want to be up 4.2, 4.4, 4.6 range. Champs Choice should be able to fix you up with some clear fixed http://www.champchoice.com/store/Main.a ... em=5422228 in the right size range for much less than an adjustable. Call and ask about the special collet that will hold the aperture centered when you change them.
As Tim has already noted, the adjustable aperture works like a a camera lens. Applies to the adjustable front and rear apertures, same principle, different location.
Now, the next mistake that new shooters often make is to use too small of a front aperture. They get themselves thinking that the smaller the white ring around the bull the more precisely they will be able to align the sights. For a number of reasons, the eye does not work that way. You will want to be up 4.2, 4.4, 4.6 range. Champs Choice should be able to fix you up with some clear fixed http://www.champchoice.com/store/Main.a ... em=5422228 in the right size range for much less than an adjustable. Call and ask about the special collet that will hold the aperture centered when you change them.