sight adapters legal for production

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contender1121
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sight adapters legal for production

Post by contender1121 »

Production rule: cannot modify gun and cannot modify sight. Is a custom made adapter legal since neither gun nor sight is being physically modified?
Specifically looking for a 11mm dovetail base that will fit a Contender rear. Similar to a Unertl Posa mount. I've combed the web looking for a factory made base with no luck.
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260 Striker
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Re: sight adapters legal for production

Post by 260 Striker »

As long as the gun AND the adapter(s) are not modified, they are legal for Production. I have seen some legal guns that had two or more adapters used together to get some peep type sights fitted to Production guns. They sure looked funny but had not been modified to fit so they were legal.
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contender1121
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Re: sight adapters legal for production

Post by contender1121 »

260 Striker wrote:As long as the gun AND the adapter(s) are not modified, they are legal for Production. I have seen some legal guns that had two or more adapters used together to get some peep type sights fitted to Production guns. They sure looked funny but had not been modified to fit so they were legal.
Thanks for the reply Lynn. I want to be sure I read you correctly. IF I was to make the adapter myself would it be legal? No mods would be made to the gun or sight. Am I reading between the lines, so to speak, that in your view the adapter(or multiples thereof) must be commercially available???
Your statement of peeps is on the mark. I'm wanting to mount a Gehmann rear sight with adjustable iris. The front (Anschutz globe) should be no problem as it sits on a standard 3/8" dovetail and there are plenty of them commercially available in varying heights to line up with the rear. I had a Williams FP-TC-TK at one time but it was on the loosey-goosey side (at least the one I had was, too much backlash).
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260 Striker
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Re: sight adapters legal for production

Post by 260 Striker »

Adapters and sights must be unmodified commercial items. NO home made adapters!!! If there are multiple parts to an adapter I don't think you have to use all the parts. By this I mean the base of a commercial sight may be mated to the bottom of the Gehmann to make it fit your gun. Parts and pieces are OK to use as long as they are commercial unmodified items.
One of our shooters has the Gehmann adjustable iris on one of his Production legal guns and I think he had to use two adapters together to make it fit. Sits up pretty high above the barrel (TC) but he uses it standing so really doesn't matter too much how high it is. I think if you called Champion Shooters Supply they might be able to give you advice on adapters.
Lynn Shultz
IHMSA #15692 since 1980
Past Match Director Logan Handgun Association
Current VP Logan Handgun Association
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United States Air Force Veteran
Retired USAF Civil Servant (47 years)
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contender1121
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Re: sight adapters legal for production

Post by contender1121 »

260 Striker wrote:Adapters and sights must be unmodified commercial items. NO home made adapters!!! If there are multiple parts to an adapter I don't think you have to use all the parts. By this I mean the base of a commercial sight may be mated to the bottom of the Gehmann to make it fit your gun. Parts and pieces are OK to use as long as they are commercial unmodified items.
One of our shooters has the Gehmann adjustable iris on one of his Production legal guns and I think he had to use two adapters together to make it fit. Sits up pretty high above the barrel (TC) but he uses it standing so really doesn't matter too much how high it is. I think if you called Champion Shooters Supply they might be able to give you advice on adapters.
That's what I figured. I'll keep looking. Putting a Gehmann adjustable iris on a non-metric sight is easy. Champions Choice sell an adapter that takes the very oddball 9.5mm X 1 thread down to a 7/32 x 40. Just gotta find that base.
Thanks again for the input.
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Re: sight adapters legal for production

Post by jmoore »

I've attached sight bases with just one screw on some .22 barrels to keep from doing mods, if that's any help. Stupid oddball spacing on TCs!
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contender1121
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Re: sight adapters legal for production

Post by contender1121 »

jmoore wrote:I've attached sight bases with just one screw on some .22 barrels to keep from doing mods, if that's any help. Stupid oddball spacing on TCs!
Well DUH!!! (as I bang my head against the wall) Wow, those .22s really kick. I better put in 4 screws and sweat solder the front sight on. #-o

And a double DUH!! The Gehmann sight (11mm dovetail) sits easily on a Unertl Posa Mount dovetail base (3/8 wide). Tightening the clamp moves the sight off of centerline about .058. The Gehmann sight has more than enough windage travel to bring the sight back to centerline and still have room for adjustment on the firing line if needed.
A classic case of overthinking. Occam's Razor definitely applies here.
THANKS for waking me up.

Note to self: make sure none of this violates rule 9A (cannot increase original sight radius more than 1 inch).
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Re: sight adapters legal for production

Post by i26963 »

http://www.champchoice.com/store/Main.a ... item=A3175
Get the .275 height. It also uses only 2 screw holes, but has not been a problem on my 300BO.
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