This is a discussion on How To Calculate Ring Height within the Optics forums, part of the Gun Forum category; A while back I made a ring height calculator since I got tired of guessing what rings to use.
I've worked it over quite a ...
A while back I made a ring height calculator since I got tired of guessing what rings to use.
I've worked it over quite a bit to make it easier to use. You'll need the distance from the top of your hand guard to the top of your scope mount rail, the distance from the top of the rear sight to the top of the rail and some specs on your scope (eyepiece OD, objective OD and tube diameter). Then enter your preferred clearance between the hand guard and rear sight ( remember to leave room for covers) and it'll show your minimum ring height. Once all that is entered you can reverse calculate it by entering a manufacturer's ring height and it'll show how much clearance you'll have.
The best way to measure is with a caliper but if close is close enough for you then a 1/32" measuring tape will work.
The spreadsheet is in Excel .xls format and free to download.
If you have any questions on it send me a PM.
As an alternative method you can stack pennies evenly on the front and back of your mount placing your scope on the stacked pennies till it clears. Then measure the stack to find out how tall of rings you need. - This wasn't my idea, just stealing it and passing it on.
Either method works, one you need the mount and scope specs, the other you need the mount and scope.
An old thread but the calculator is very useful. I'm rigging up my M14 for a new scope (I can't get my Super Sniper serviced here in Canada) so once I select a new scope, I can then figure out what rings to buy.