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Sport Cantilever 30 mm Ring

1-Inch Offset | Lower 1/3 Co-Witness

Sport Cantilever 30 mm Ring Click to Enlarge
SKU: CM-304
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MSRP: $39.99
*Prices in US Dollars
Reviews:
Sport Cantilever 30 mm Ring is rated 5.0 out of 5 by 1.
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Sport Cantilever 30mm Ring— Lower 1/3 Co-Witness | 1-inch Offset

Provides extra rail room for rear Back Up Iron Sights (BUIS) when using the StrikeFire red dot along with the VMX-3T magnifier. The cantilever ring will move the StrikeFire forward about one inch.

Note
Provides lower 1/3 co-witness mounting height of 40 mm. Will work with most 30 mm red dot sights.



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Recommended Torque Specs
Base Clamp Hex Nut Ring Screws
35–45 in/lbs 15–20 in/lbs
Rated 5 out of 5 by from Light, compact and sturdy Used this mount for my Strikefire II. After a thousand rounds, it still holds true!
Date published: 2017-06-15
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What is the height above bore axis with the lower 1/3 and absolute cowitness on an ar-15?

Asked by: Tulrey136
Lower 1/3 is roughly 2.9 inches and absolute co-witness would be roughly 2.5 inches on most AR platforms. Some AR-15's have a monolithic rail which will add to the height over bore. This additional height is not consistent from brand to brand.
Answered by: Josh at Vortex Optics
Date published: 2018-05-14

Should the 'lower 1/3 co-witness (Sport) cantilever mount' be used with the 'tactical (single-ring) extra-high lower 1/3 co-witness mount' as a conventional riflescope mounting scheme to mount a Vortex StrikeEagle - will this damage the scope?

Asked by: Parliament
I do not recommend going that route as those rings are designed for single ring use and are not intended for use on a rifle scope. If you are looking for a mount that high, any of our 1 piece cantilever mounts would offer a better mounting solution.
Answered by: Mike at Vortex Optics
Date published: 2017-12-05

A picture of CM304 and CM305 looks just similar. What is different? Is the height different? Please by mm

Asked by: Mackey
The heights are different, the CM 304 mounts the center of the optic to 40 mm and the CM 305 mounts the center of the optic at 37 mm.
Answered by: Mike at Vortex Optics
Date published: 2017-10-16

I am confused. Which ring the co-wistness or the 1/3 lower is in fact lower? Seems like the 1/3 lower would be. This is for a crossbow scope, not an AR, so I want it as low as possible. thanks

Asked by: dusty
Absolute co-witness height would be lower than lower 1/3 co-witness. It refers to where the iron sights are inside of an optic, absolute co-witness puts the iron sights at the same height as the dot while lower 1/3 co-witness means the iron sights are below the dot.
Answered by: Mike at Vortex Optics
Date published: 2018-03-22

Hi, I just bought the new AR-15 by Springfield. I am wanting to put a StrikeFire ll and a VMX-3T Magnifier with flip mount. My question is which mount would work best, the cantilever 30mm absolute co-witness or the lower 1/3 co-witness mount?
Asked by: Deuce
Both mount heights work equally well and the magnifier has a shim included to make sure you can get proper alignment with each. It just depends on what sight picture you would prefer.
Answered by: Jon from Sales
Date published: 2017-06-15

How much does this mount weigh?
Asked by: Mike
the mount weights 4 oz.
Answered by: Mike at Vortex Optics
Date published: 2017-06-15

How much does this mount weight?
Asked by: Mike
It weighs 4 oz.
Answered by: Jon from Sales
Date published: 2017-06-15

If using flip up sights, what difference will the absolute or lower 1/3 co-witness make?
Asked by: frybry
Absolute co-witness will mean that the red dot would be exactly in line with your iron sights if they were flipped up. Lower 1/3 co-witness puts the sight higher above the iron sights if they were flipped up so that the iron sights are out of the way and you can just shoot off of the dot. It all comes down to personal preference and which setup you feel would be most comfortable for you to shoot in. If you have any other questions about this or need any clarification, please shoot me an e-mail at raleckson@vortexoptics.com thanks!
Answered by: Reuben
Date published: 2018-01-22
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