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Old 04-20-2013, 03:31 AM   #1
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Default Riser Height?

What do you think would be the lowest riser that would either co witness the A2 front sight or clear it? Would a 1/2 inch riser be high enough? I'm running a cheappy non magnified red dot 40mm. I don't like the riser I'm currently running as the MBUS won't fit on the rail with it on there. I'd like to go a little lower if I can. This riser easily clears the front sight. (I can still see the front sight through the red dot with this current set up)



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Old 04-20-2013, 02:06 PM   #2
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The a-2 sight height is 2.25 if I am not mistaken measure from the center of your optic to where it meets the top of your picitany rail and then subtract that from 2.25 and that will give you the height of the riser you need.



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Old 04-20-2013, 11:14 PM   #3
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Thanks for the info. I'll check it out.

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Old 04-20-2013, 11:43 PM   #4
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Actually I am a little off on that. The sight height is 2.25 inches from the bore line not the top of the rail, you also have to subtract the height to the top of the rail which is about 1.2 inches. So you actually need to subtract the height if you optic from 1.05 inches to get a perfect co-witness however one inch will work fine. Sorry about that I wasn't thinking it all the way through probably shouldn't make forum posts before noon.

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Old 04-21-2013, 09:34 PM   #5
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Went with a 1/2 inch riser and it's now co-witnessed. Thanks for the help. I know it's a cheap WM red dot...next rifle I'm going to build and it will be upgraded

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Old 04-22-2013, 02:15 PM   #6
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That first riser was about 4" long! No wonder there wasn't rail left for the MBUS!

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Old 04-22-2013, 08:08 PM   #7
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Quote:
Originally Posted by Quentin View Post
That first riser was about 4" long! No wonder there wasn't rail left for the MBUS!
Ya, I figured that out about 5 seconds after installing it! LOL
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Old 04-22-2013, 11:39 PM   #8
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Quote:
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Ya, I figured that out about 5 seconds after installing it! LOL
Yeah, not making fun of you... I've got one of those things stuffed in a drawer somewhere, too!


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