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Gehmann Globe front sight aperture and a Centra LR rear base

1 by sikacz
I’m in the process of buying a 22mm front sight holder. I’m basically setting the rifle for distance. The rear sight I ordered is a Centra LR base. I have not bought an adjustable rear iris, later. I need a bit of help explaining my options on the front aperture. I’m attaching the three size options shown in parentheses. The pictures look identical, so what does the number range mean? Is each more suited to a shooting distance, light condition or just shooter preference?

Additional info, sight radius approximately 30”.

Additional info.
Last edited by sikacz on Thu Nov 12, 2020 7:28 pm, edited 3 times in total.
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"Resistance is futile. You will be assimilated!" Loquacious of many. Texas Chapter Chief Cat Herder.
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Re: Globe front sight aperture

2 by Mason
Usually, for target shooting you want the inside of the ring to be just barely larger than the target at the distance you are shooting. That's how we did it when I shot 25M target in high school. There were five targets about an inch and a half diameter and you put one bullet into each. I can't decode what is meant by the descriptions.
'Sorry stupid people but there are some definite disadvantages to being stupid."

-John Cleese

Re: Globe front sight aperture

3 by sikacz
Mason wrote: Mon Nov 09, 2020 9:41 am Usually, for target shooting you want the inside of the ring to be just barely larger than the target at the distance you are shooting. That's how we did it when I shot 25M target in high school. There were five targets about an inch and a half diameter and you put one bullet into each. I can't decode what is meant by the descriptions.
That sounds vaguely like what I understood. Vaguely not because of your explanation, but my inexperience. If I've understood correctly the larger range is preferred by some when the sight radius is long. I'm guessing they are also talking about rifles with a bloop tube setup. I have no idea how the target will appear at 300-400 plus range. Perhaps out of ignorance I'll just have to take a guess, so far I'm guessing the middle range. Thanks Mason for that explanation. It helped take some of the fuzz off my understanding which is still fuzzy, but less so.
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"Resistance is futile. You will be assimilated!" Loquacious of many. Texas Chapter Chief Cat Herder.

Re: Gehmann Globe front sight aperture and a Centra LR rear base

14 by sikacz
lurker wrote: Fri Nov 13, 2020 3:46 pm have you tried aluminum beer can for shim material?
No, but that sounds like a great idea. I ordered some shim stock from Brownell’s and it’s coming in Monday. I took a strip of paper and rolled it several times over just to see how the parts fit. I’m going to keep the beer can idea in mind though. LoL.
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"Resistance is futile. You will be assimilated!" Loquacious of many. Texas Chapter Chief Cat Herder.

Re: Gehmann Globe front sight aperture and a Centra LR rear base

17 by Mason
There is a passage where the author is working on his not mechanically inclined, but well off friends brand new BMW bike because the handlebars can’t be tightened in the stem clamp. The friend is horrified when the author cuts a PIECE OF OLD BEER CAN to fix his brand new, shiny and very expensive new bike. It stuck with me.
'Sorry stupid people but there are some definite disadvantages to being stupid."

-John Cleese

Re: Gehmann Globe front sight aperture and a Centra LR rear base

18 by sikacz
Mason wrote: Fri Nov 13, 2020 4:23 pm There is a passage where the author is working on his not mechanically inclined, but well off friends brand new BMW bike because the handlebars can’t be tightened in the stem clamp. The friend is horrified when the author cuts a PIECE OF OLD BEER CAN to fix his brand new, shiny and very expensive new bike. It stuck with me.
I love it! LoL. Whatever works, good practical engineering.
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"Resistance is futile. You will be assimilated!" Loquacious of many. Texas Chapter Chief Cat Herder.

Re: Gehmann Globe front sight aperture and a Centra LR rear base

23 by sikacz
lurker wrote: Sat Nov 14, 2020 10:18 am
sikacz wrote: Sat Nov 14, 2020 9:09 am Anyone have an idea which side of the sight holder faces the muzzle? Is the adjustment ring to the front or back?
orient it so you can read the lettering between shots. just an idea.
I’m guessing this way. The iris can only go on one side. The thread is shorter on the other side which is probably for a sun glare tube.
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"Resistance is futile. You will be assimilated!" Loquacious of many. Texas Chapter Chief Cat Herder.
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