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John Hwang
18 March 2010, 10:42
Description:

American Rifle’s M3 Scope Mount is a comprehensive scope mounting solution engineered to provide maximum clamping force without damaging the scope tube.

Unique to the M3 patent pending design is a hinge on one side and an overlapping interface on the other used to secure the scope. The hinge minimizes the number of screws used to clamp the scope. The overlapping interface stems from the placement of those screws, which is critical to securing the scope without damaging it. The screws are tangent to the scope tube so that when tightened, the ring cap is pulled down over the scope tube without bending in a way that will damage the scope.

Tightening the screws of American Rifle’s M3 Scope Mount when installing the scope will not alter the reticle alignment. Additionally, the bottom part of the ring saddles the scope along 180 degrees of its circumference preventing the scope from moving laterally within the ring as the screws are tightened.

American Rifle used finite element analysis (FEA) to engineer a scope ring that optimally distributes clamping forces over the scope tube. A force of 500 pounds* was applied at each screw location during the analysis to simulate the forces imparted by the screws. As depicted in the resulting stress plots below, the M3’s tangential scope clamp evenly distributes the clamp forces over the tube. As a result, no significant stress concentrations are present on the scope tube.

Low Ring Height:

* 1″ - 25MM
* 30MM - 25MM
* 35MM - 28MM


High Rings Height: 35MM for all 3 Ring Sizes


Offered in 3 Sizes

* 1″ Rings
* 30MM Rings
* 35MM Rings


http://www.rainierarms.com/img/shop/product/9ee2e49b10ee9e5c393dddf5b36472d3.jpg (http://americanrifle.com/)


http://www.rainierarms.com/img/shop/product/39be3a1e2dd1ea452830ef34803c1eef.jpg (http://americanrifle.com/)



http://www.rainierarms.com/img/shop/product/331b02dd549ca3e9de878a6720751a69.jpg (http://americanrifle.com/)

John Hwang
18 March 2010, 10:47
In stark contrast, all other rings use screws which are offset from the scope tube by some distance. FEA was used to visualize the stress within the scope tube caused by forces imparted by these offset screws. Again, a 500 pound force was applied at each screw location during the analysis. The resulting stress plots show the stress concentration (red) present within the scope tube near the joint between the upper and lower parts of the ring assembly. The forces imparted by the offset screws drive the proximal corner of the ring cap into the scope tube causing the stress concentration. This can indent the scope tube or mar its finish. Furthermore, when the rings of these mounting systems are misaligned with respect to one another, the stress concentration can be further intensified.



http://americanrifle.com/images/graphics/m3-1-00_tangent_screw_axis_rev_b_S.jpg (http://americanrifle.com/images/graphics/m3-1-00_tangent_screw_axis_rev_b_L.jpg)



http://americanrifle.com/images/graphics/arc_iso_with_cap_S.jpg (http://americanrifle.com/images/graphics/arc_iso_with_cap_L.jpg)



American Rifle’s M3 Scope Mount is engineered to provide a comprehensive scope mounting solution. No other scope mount can provide as tight a grip without damaging the optic.




http://americanrifle.com/images/graphics/offset_screw_forces_rev_B_S.jpg (http://americanrifle.com/images/graphics/offset_screw_forces_rev_B_L.jpg)



http://americanrifle.com/images/graphics/pri_iso_with_cap_S.jpg (http://americanrifle.com/images/graphics/pri_iso_with_cap_L.jpg)

John Hwang
18 March 2010, 10:49
American Rifle’s M3 Scope Mount is a comprehensive scope mounting solution engineered to properly engage Mil-Std-1913 (Picatinny) accessory rails and guarantee “return-to-zero” performance.

Unique to the M3 patent pending design is a crowned rail interface capable of properly engaging rails having widths as much as 0.01 inches (0.38 mm) and angles as much as 5° above or below those prescribed by the Mil-Std-1913 specification. As shown in the figures below, the M3 crowned rail interface contacts the dovetail of the rail avoiding contact with the edges regardless of substantial variations in the width or angle of the rail profile. This ensures the precise engagement required for “return-to-zero” performance.


http://americanrifle.com/images/graphics/m3-1-00_crowned_rail_int_closeup_S.jpg



http://americanrifle.com/images/graphics/m3_0n_nom_under_and_over_rail_L.jpg

Other mounts have flat rail interface surfaces which do not accommodate variations in width or angle of the rail profile without substantial edge contact. Under the forces imparted by the rail clamp and recoil, edge contact results in high stress that can permanently deform the rail interface compromising precision. The figures below illustrate how other interface designs fail to properly engage the rail.


http://americanrifle.com/images/graphics/competitors_dt%20interface_L.jpg

To prevent edge contact, other manufacturers must rely on an unrealistic perfect fit between their mounts and the rails they must engage. The ability to cope with variations in rail geometry sets American Rifle’s M3 Scope Mount far apart from the competition.