Tech

9mm Major (pt 1)

by on 11/09/2015
 


If you’re involved in competition pistol shooting and have an interest in hot rod competition guns, you may of heard the term “9mm Major.” This refers to a 9mm round that is rocket loaded to .357 velocities. It is much hotter than anything sold commercially and designed to run in high end open class pistols for run and gun pistol matches. This is drag racing in the pistol world and race guns need race ammo.

bullet weight X velocity /1000 = 165+
(exp. 124gr X 1331 = 165.044 / 1000 = 165.044PF )

The 9×19 case is loaded to meet the USPSA 165 Power Factor then fired over a chronograph with the pistol being used in competition. The power factor is calculated by multiplying bullet weight (in grains, 7,000gr to the pound) by muzzle velocity (in feet per second), then dividing by 1000. A value of 165 or greater is considered Major, while values below 165 are Minor.


Power factor is used for scoring. On a USPSA target the center “A” zone is scored 5 points regardless of if you’re shooting major or minor. The outer “C” zone is scored 4 points for major and 3 points for minor. The outermost “D” zone is 2 points for major and only 1 point for minor. What this means is those shooting major power factor can push the speed as sloppy hits can be absorbed as long as you’re getting mostly alpha hits. If you’re shooting minor you need to slow down and shoot all alphas as sloppy hits are very expensive. Each USPSA target requires 2 best hits for score for a max of 10 points per target.


In USPSA competition, only Open Class is allowed to shoot and score 9mm Major. While 9mm Major may be shot from a more traditional iron sighted non-compensated pistol it will be scored as minor PF in both Production and Limited class. In other words, if you have a “regular gun” there is no scoring advantage to shooting 9mm Major. If you are shooting open class on the other hand, 9mm Major is the most cost and labor effective way to feed your gun. The alternative, .38 Super, is more expensive. Those shooters who desire to run an open class pistol get a number of advantages such as a red dot optic, a 170mm long magazine (28+ rounds) and a barrel with porting and/or a attached compensator.


Compensators are critical to a flat shooting 9mm Major open gun. Just like the muzzle brake on a rifle, it is a device attached to the end of the barrel that redirects gasses to counter recoil. Typically, major is loaded with slow burning powder that generates extra gas and pressure. The blast as it enters the comp pulls the gun forward and then is directed up or to the sides to stabilize the gun. A hotter load can be shot with substantially reduced recoil. The redirected gasses can be vented upwards to reduce muzzle rise. Ideally the red dot from the pistol optic should just wiggle when fired and not recoil off target.

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