|
Chris Farris
TEAM SWFA - Admin swfa.com
Joined: 01/October/2003 Location: Texas Online Status: Offline Posts: 5084 |
Post Options
Quote Reply Topic: How to determine proper ring height Posted: 22/February/2007 at 14:28 |
Measure the outside diameter of your scope's objective, then divide by that by two.
Super Sniper 10x42 has an O.D. of 50mm. 50/2=25mm (.98")
This will be the dimension above which the ring and bases combined will need to raise the scope's centerline to clear a barrel that is the same diameter as the action..
Once you have that key dimension, all you need to do is select a base and ring combination that equals that dimension plus 3mm-5mm to accommodate lens covers.
25mm+3mm=28mm (1.10")
Figure out how thick the base is. IE: Badger Ordnance Remington 700 base is 7mm thick.
28mm-7mm=21mm (.82")
Now you need rings which will take up the rest of the dimension. This is where you need to pay attention because this is where most of the confusion and inconsistencies come from. Manufacturer's ring heights are not uniform from brand to brand, IE: Burris' low is not the same as Leupold's low. Ignore their descriptions and go by the actual measurement of the ring. The actual measurement of "ring height" is determined two different ways. Some measure from the top of the base (where the ring contacts it) to the centerline of the ring (Fig. A). Others measure from the top of the base to where the ring first contacts the scope (Fig. B). If the brand you are considering measures their ring height like Fig. B, you will need to add 12.7mm for one inch scope and 15mm for 30mm scopes to get to the centerline of the ring which is also the center line of the scope.
Badger Ordnance provides both measurements. For the example Super Sniper on a Remington 700 we need a ring with a height of .82". Badger Ordnance stock number 30680 measures .823" so these are the ring we would select.
http://www.swfa.com/c-55-badger-ordnance-mounts.aspx
http://www.badgerordnance.com/index.php
http://www.convertunits.com/from/inches/to/mm
Edited by Chris Farris |
|
|
Ejsg19
Optics GrassHopper
Joined: March/25/2009
Location: Minneapolis
Status: Offline
Points: 6
|
Post Options
Thanks(0)
Quote Reply
Posted: March/26/2009 at 23:00 |
Yep I read through that the other day, and it does help a lot, except the makers of the rings don't list the actual dimensions. Therefore knowing your measurements is all but useless unless you are looking at Badger rings, those actually list the dimensions.
For Burris Signature 1'' rings, they say "low, med, high, etc" which means almost nothing, other than I know for a fact that the low's or medium heights will be too short. So I wonder if I need the high rings, or the next taller set still to clear everything without being unnecessarily high.
|
EJSG19
|
|
Ejsg19
Optics GrassHopper
Joined: March/25/2009
Location: Minneapolis
Status: Offline
Points: 6
|
Post Options
Thanks(0)
Quote Reply
Posted: March/27/2009 at 09:40 |
Well I haven't given up yet, after emails to various places, Burris' customer service replied telling me that the distance from the base to the bottom of the ring where it contacts the scope is about 0.390'' for the High Burris Signature Rings. So you add half an inch and there is your centerline, and you can figure out estimated clearance after that.
Then Chris Farris' explanation of how to find ring height works just fine!
Hope this helps anyone in the same boat.
|
EJSG19
|
|
Sgt. D
Optics Master Extraordinaire
Joined: February/20/2008
Location: North Carolina
Status: Offline
Points: 4525
|
Post Options
Thanks(0)
Quote Reply
Posted: March/27/2009 at 10:08 |
Quote) I know for a fact that the low's or medium heights will be too short. So I wonder if I need the high rings, or the next taller set still to clear everything without being unnecessarily high. Quote)
Yes sir you've found that hard place for info. That is one reason Chris gave us that post. I am currently having a similar problem. And who wants to spend on a guess. I don't have a set up like you describe, but I will check around to see if I can get some measurements on some ring heights. As you have determined the high rings seem to be the best fit, but I can't give you absolute. For your aplication the dove tail should be fine. You will always find folk that hate them, but like anything else the pros out weigh the cons.
In seeing your last post you had to get your own answers and that has saved some folk some leg work. Good job. I'll be recording that measure for future use. Hate this was such a dry thread, but sometimes it'll happen. Welcome to the OT, and good luck with your 223.
|
Take care of Soldiers, Show em how its done and do it with em, Run to the Fight & and hold your ground! I die my men go home! If you're a NCO and this ain't you. GET OUT! GOD BLESS AMERICA!
|
|
Dogger
Optics Jedi Master
Joined: January/02/2007
Location: Ontario, Canada
Status: Offline
Points: 8915
|
Post Options
Thanks(0)
Quote Reply
Posted: March/27/2009 at 10:12 |
That Burris site was not particularly helpful was it? Think I will send them an email to see if they can include base to centreline height.
Updated to add:
Sent an email to their cx service to see if they will add measurement "A" to the site.
Edited by Dogger - March/27/2009 at 10:20
|
God save the Empire!
|
|
Ejsg19
Optics GrassHopper
Joined: March/25/2009
Location: Minneapolis
Status: Offline
Points: 6
|
Post Options
Thanks(0)
Quote Reply
Posted: March/27/2009 at 10:23 |
Hey no worries guys. If somebody doesn't have the answer off the top of their head then I go into phase two of my research and start hitting the phones/emails. I have a problem with over-researching things, and it saves me a lot of time if somebody else has already been through it! But I'm willing if need be. Anyway...
Using Chris's method, I find that a "B" measurement of .390'' (9.906mm) on the Burris Signature High rings is a REAL tight fit, not even sure if it will clearance the lens covers.
Here is the math. If you guys are really bored or interested, one of the two. Or if you see a mistake please point it out!
.390'' = 9.906mm My Nikon Monarch has on O.D. at the objective of 57.3mm (So I'm trying to clear a distance of 28.65mm to the center of the rings as I understand it).
9.906mm
+12.70mm (gets us to the "A" measurement or centerline of the rings)
= 22.606mm
+ 6.35mm (estimating 1/4 inch on the bases for dovetail bases could be a little more or less)
= 28.956mm = total height/clearance
So 28.956mm minus the required 28.65mm equals only 0.306mm of wiggle room!!!
Don't know if the Burris Signatures come a size higher or not. Could go with the Burris extreme tacticals, those are taller. Or maybe I should look beyond burris? Thoughts?
|
EJSG19
|
|
Dogger
Optics Jedi Master
Joined: January/02/2007
Location: Ontario, Canada
Status: Offline
Points: 8915
|
Post Options
Thanks(0)
Quote Reply
Posted: March/27/2009 at 10:39 |
Sounds close, not enough experience with that to know for sure without trial and error. Going on a .223 so scope flex under recoil should not be an issue. If it is too close could use a shim I guess but not a real elegant solution.
|
God save the Empire!
|
|
Sgt. D
Optics Master Extraordinaire
Joined: February/20/2008
Location: North Carolina
Status: Offline
Points: 4525
|
Post Options
Thanks(0)
Quote Reply
Posted: March/27/2009 at 10:51 |
When you add lens covers keeping a low mount won't happen. I wouldn't risk it unless you are willing to drop the covers if its too close. Just as well go with extra- high and carry on. Unless you have access to a machine shop and can build custom or mill some height off.
|
Take care of Soldiers, Show em how its done and do it with em, Run to the Fight & and hold your ground! I die my men go home! If you're a NCO and this ain't you. GET OUT! GOD BLESS AMERICA!
|
|
Ejsg19
Optics GrassHopper
Joined: March/25/2009
Location: Minneapolis
Status: Offline
Points: 6
|
Post Options
Thanks(0)
Quote Reply
Posted: March/30/2009 at 14:22 |
Well it turns out the margin for error was a little bigger than I first thought. Was trying to crunch out some solid numbers at work the other day, and forgot to look at the contour of the rifle receiver in relation to the barrel.
If you look at the Savage 12 Varminter LP, the receiver sits maybe 1/4''-3/8'' higher than does the barrel where the objective lense would be. So I think I have quite a bit more space than my math up above suggests.
I just wanted to add that to anyone in the future who might be looking through this thread.
I have a set of Burris Signature 1'' High rings in Matte black on the way, with a 2 piece Leupold dovetail base, with the windage adjustment on the rear piece coming.
Unfortunately, swfa's website refused to cooperate and kept logging me out and wouldn't keep track of what was in the cart, and then wouldn't checkout properly. So I ordered from competitor. No disrespect to anyone, but it was free shipping and about $14 cheaper than SWFA had it. Rings and bases ordered for $41 and some change.
|
EJSG19
|
|