Case life of 9mm brass. Reloading Armscor 9mm brass

In this blog we examine and test fire Armscor 124 gr FMJ 9mm ammo. We are looking at how it performs and how re-loadable the once fired brass is. Armscor ammunition, located in Stevensville, Montana manufacturers this 9mm ammunition with the head stamp "ARMSCOR USA 9MM LUGER". Their website is www.armscorusa.com. The following information is directly quoted from their web site.
 “ARMSCOR Small Arms Ammunition line is one of the largest and most comprehensive in Southeast Asia. The Company offers a wide selection of competitively priced ammunition and components with sales spread throughout the world.
ARMSCOR, an ISO 9001 Certified Company, complies with the SAAMI, CIP and other military or customer desired standards or requirements.
ARMSCOR cartridges and components are widely used by the police, military, gun hobbyist, combat shooters and other shooting enthusiast due to its high quality, precise and dependable performance. “

Armscor factory new ammo in the box

We purchased factory new ammo and examined it. We disassembled one of the cartridges and found that the projectile was a 124.9 grain FMJ brass round nose with a flat base. The brass jacket did not encase the base of the bullet where the exposed flat based lead core was noted. The FMJ bullets were smooth and free of surface manufacturing defects. The powder had irregular morphology with spheres, disks and irregular flakes, and weighed 4.1 grains. The primer was a brass cup and had an internal tripod anvil assembly very similar to a CCI small pistol primer.

Projectile and propellant

We then test fired the remaining 49 rounds of this ammunition through a Taurus PT 99 AF 9 mm handgun. The same weapon used in the previous tests.  Prior to firing, we weighed each cartridge and found that this ammunition had an average weight of the 191.8 grains per cartridge, the heaviest round was 193.5 grains and the lightest was 190.4 grains. The standard deviation was .6 grains.

We measured the velocity of each of the rounds using a Pro Chronograph digital chronograph and found that the average velocity of this ammunition was 1177 ft./s. the slowest round had a velocity of 1159 ft./s 15 feet from the barrel, and the fastest round had a velocity of 1195 ft./s.  There was a standard deviation of 8 ft./s. The ammunition performed flawlessly through the weapon. There were no failures to feed or eject.

We ran the spent cases through a Lee resizing and depriming die and found the brass to move very smoothly through the process without any irregularities in the primer burn hole centering or diameter which adversely affected de-priming. Visual examination of the interior of the case showed a smooth interior cup. The base of the cup was flat and the burn hole had an irregular circular opening due to burrs at its edges. The burs were compressed flat around the lip of the burn hole. Primer seating and fit was snug and smooth with Winchester, Federal, Wolf, CCI, Magtech, and Remington small pistol primers.

Note irregular shape of burn hole due to flattened burrs

Our impression of the Armscor 9mm 124 grain FMJ ammo is favorable. It has “precise and dependable” performance as promised. It burns cleanly. A very low standard deviation in velocity and a good standard deviation in the weight of the cartridges indicate a consistent quality manufacturing process. All the materials used to assemble the cartridges seem to be of high quality. Performance through the weapon was flawless. Accuracy was not tested.

Our primary interest is in the reload-ability of the brass. Our initial impression here is also favorable. It is easy to work with.  It cleans easily. It runs through our dies easily. It has consistently good seating in the primer pocket of a wide variety of primers.  Seating was smooth and firm with each, and did not loosen at all with repeated reloading.  The reloads function flawlessly through the test weapon.

We reloaded and fired two cases to failure and found the  ANBF (average number of times a case can be reloaded prior to failing) to be 30. As in all other cases tested, the failures were small splits at the case mouth.  This ANBF places Armscor in the company of Independence, Sellier & Bellot and Ammo Tech with a solid ANBF (see chart below), but well below Winchester, Aguila and CBC for longevity.  Armscor 9mm ammo rates very highly as factory new ammo and the brass was a solid performer for reloading. Armscor brass goes on our “reload with confidence” list with a note about a less than average lifespan.

Updated data as of 9/29/2012