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How to determine proper ring height

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SVT_Tactical View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote SVT_Tactical Quote  Post ReplyReply Direct Link To This Post Posted: October/28/2010 at 10:33
what are you putting this on?

Edited by SVT_Tactical - October/28/2010 at 10:34
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Post Options Post Options   Thanks (0) Thanks(0)   Quote grimreaper21 Quote  Post ReplyReply Direct Link To This Post Posted: October/28/2010 at 12:22
17'' of ar15 rail space.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote grimreaper21 Quote  Post ReplyReply Direct Link To This Post Posted: October/28/2010 at 13:01
think i know what i did wrong, the +12.7 is in addition to the ring size not the objlens diam.

so it would be 50/2 = 25objlens + 3lenscover = 28mm.
 
compared against 27.686mm (1.09'') + 12.7mm = 40.386mm.  so these are actually around 12mm taller than needed?  I would want around 30mm for this application.

medium rings would be 17.7038mm (.697'') + 12.7mm = 30.40 compared to 28mm, with a nice buffer.
or am i losing it again Loco
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Post Options Post Options   Thanks (0) Thanks(0)   Quote gundudeusa Quote  Post ReplyReply Direct Link To This Post Posted: March/01/2013 at 16:27
Here's a calculator I made recently. Hopefully this will help all future readers. Comes with many modern scope and ring height preset values. Also accounts for Butler scope cover and scope mount cant.

http://www.mil-rad.com/scope_ring_calculator
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Post Options Post Options   Thanks (0) Thanks(0)   Quote FelixV Quote  Post ReplyReply Direct Link To This Post Posted: November/17/2013 at 11:39
Greetings!!
This is my first post.
 
A 50mm Objective bell on a 30mm tube holds a simple example for proper ring height.
50mm-30mm=20mm/2=10mm That is how high the bottom of the tube will be when the objective bell is leveled on a flat surface.  Thickness of your base, plus the B measurement of the rings, bottom of ring to the lowest point inside the lower ring, (where the tube rests), obviously must exceed 10mm. How far beyond lifting the bell more than 10mm is the key. That clearance is up to you but I would concur with Chris.  This method can also be used with 1" tubes when converted.

Hope this simplifies


FelixV
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Accidic Quote  Post ReplyReply Direct Link To This Post Posted: April/29/2015 at 16:13
This explains it very well for me but and I follow the figures for the calc portion.  My only curiousity is do the elevated rails sit at a slight angle?  (IE, 20MOA picatinny rails)  Or is this just an elevation thing that achieves it through the elevation.   I ask as I saw one where they suggested milling a rail to get a more aggressive angle and it left me rather confused.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote cheaptrick Quote  Post ReplyReply Direct Link To This Post Posted: April/29/2015 at 21:33
Yes, a 20 MOA rail will slightly lower and make your scope's obj closer to the bore than a flat rail, if I read your question correctly. 
Or are you asking how a canted rail works?    
If at first you don't secede...try..try again.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Chris Farris Quote  Post ReplyReply Direct Link To This Post Posted: May/12/2015 at 14:57
Scope Ring Height and Clearance Calculator
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Post Options Post Options   Thanks (0) Thanks(0)   Quote GunsIsFuns Quote  Post ReplyReply Direct Link To This Post Posted: September/20/2015 at 21:52

Wish I saw this a few weeks ago.  But I think I my AR should be good with the mount I have coming in the mail.


http://swfa.com/Aero-Precision-Ultralight-30mm-One-Piece-Scope-Mount-P79089.aspx

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Post Options Post Options   Thanks (0) Thanks(0)   Quote EricX Quote  Post ReplyReply Direct Link To This Post Posted: November/16/2015 at 02:14
Hey guys!
This might be one for the books but something that needs to be addressed for future use from others...
I have a Ruger RPR with a 20MOA base upper receiver then a level railed handguard (currently the stock Sampson but soon to have a Midwest Industries RPR handguard).
I've seen good info here on clearance on most rifles and even with an AR platform but the 20MOA angle of the RPR receiver to the flat to barrel axis handguard has me really perplexed.
OK, the scope I am looking at is the 6.5-20x50 Vortex Viper... I would love a SWFA SS HD 5-20X50 but I am on a really restricted budget (grad school student; go figure) so the Vortex is the best option for my application and budget.
The Mil-Rad Scope Ring Height and Clearance Calculator app doesn't work for me for some reason (browser issues?), so I gotta "go analog" and get advice from RKI's.
I plan on using the SWFA SS-Tac or Vortex Tactical rings (pretty sure those are the best value for the dollar out there) with the Vortex 6.5-20x50 with either Vortex or Butler Creek caps on it (no sunshade).
SO... what are the lowest profile rings that will work?
If it were flat, I was thinking standard HIGH to be easily safe but will the 20MOA down-angle warrant Xtra high? I'd prefer as low profile as possible.
So... what rings do the experts suggest for this setup?
Thanks in advance for any RKI advice.
~EricX
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Post Options Post Options   Thanks (0) Thanks(0)   Quote RickCunn Quote  Post ReplyReply Direct Link To This Post Posted: May/03/2017 at 17:59
Being an optics newbie, maybe I am missing something here.  What about cheek weld and comfort when determining ring height?  The ring height calculators provide the minimum distance to ensure clearance. However, depending upon stock shape and dimensions, and the dimensions of my head, even for rings that place the scope at the right height the rings may not be tall enough.  I've got one rifle that with the low rings I end up having to cram my face against the stock really hard.  So rings that are en extra 1/2 inch or so taller than the minimum needed to clear the stock are needed for my comfort.  I have another rifle that the low rings work just fine, at least as far as comfort goes.  My point is, I think there is more to ring height than just clearance.  



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