It put the barrel, and the bore axis
, closer to the hand.
As I have written before, one of the advantages of a striker-fired mechanism has to do with the relationship between the bore axis
and shooter comfort.
Though the bore axis
is fairly high the frame remains undercut.
If you've shot an M&P you know its low bore axis
and 18-degree grip angle make it easy to shoot well, and the gun comes with four interchangeable grip inserts--small, medium, medium/ large and large--as well as the aformentioned new grip stippling, which is a lot more aggressive for excellent control.
Some will complain that the bore axis
on the 509 T, like the 509, is higher than on other pistols.
Regarding anti-tilt pads ("Combating AR-15 Bolt Carrier Tilt", May 2017), when adjusting the screws to uniform the gap at the rear of the bolt carrier group, is it better to try to even the gap around the carrier or adjust it parallel with the bore axis
? For example, say your carrier is undersized and adjusting the tilt to get a uniform gap in the back imparts a forward tilt on the carrier.
p--pressure, [mu]--viscosity coefficient, U--velocity component, tangential to the bore surface, V--velocity component, perpendicular to the bore surface W--velocity of piston motion along the bore axis
(considering the piston incline), h--fluid film thickness, v--velocity component, perpendicular to the piston surface, u--velocity component, tangential to the piston surface, w--velocity of piston motion along its axis (not considering the piston incline), [omega]--the machine shaft rotation frequency, [phi]--angular coordinate of a point on the piston surface.
When the rotor eccentricity refers displacement axis rotor stator bore axis
On these rifles, whether iron-sighted or topped with optics, the line of sight is distinctly higher than the line of the bore axis
. Since rifles are typically sighted in for 100 yards or more, this means at home-defense distances, point of impact will be dramatically lower than point of aim.
The result is a far more concentric and consistent alignment of the bullet with the bore axis
, more positive and non-distorted land/groove engagement, consequent enhanced accuracy and less wear and tear on the bore.
The XD-S is a striker-fired design offering a lower bore axis
than what is usually found on a comparable hammer-fired equivalent.