Introducing, UDMC's S-22LR Semi-Automatic Rifle

We are pleased to announce the launch of UDMC’s S-22LR Mini AR Rifle whose prototypes are presented in the picture. This latest product of UDMC will be marketed exclusively by United Defense Manufacturing Corp. and PAD-Parañaque Arms Depot Inc. Contact details on Facebook: Juvy-An Catipay, MO Marcelino and Marc Nieves. For emails:



United Defense Mfg Corp’s S-22LR is a caliber .22LR rim-fired rifle that employs a simple blowback self-loading system of firing sequence that uses a box magazine to feed the round into the chamber through the energy coming from the rearward motion of the spent case resulting from the expanding gases created by the ignition of the gunpowder.

"The blowback system is generally defined as an operating system in which energy to operate the firearm’s various mechanisms and provide automation is derived from the movement of the spent cartridge case pushed out of the chamber by rapidly expanding powder gases. This rearward thrust, imparted against the breech, is a direct result of the expansion of propellant gases." [George M. Chinn 1955]

The S-22LR Semi-Automatic Rifle was designed by UDMC in the AR platform. It looks and feels exactly like an AR rifle though lighter in weight. Its lower receiver uses the same T6-7075 aluminum like the milspecs M4 and has almost the same dimensions as the lower receiver as the M4 rifle except in the lower end plate where cuts were machined in order to prevent the installation of a hollow tube with the same action spring and buffer as the M4. If one attempts to machine-thread the end plate of the receiver, the end plate portion simple breaks-up into two parts. For the upper receiver, the S-22LR uses the T6-6061 aluminum that looks also similar to an AR upper receiver minus the bigger ejection port and ejection port cover.

- Commercial Sporting Rifle

Country of Origin
- U.S.A.

- 1960’s for the AR platform

- United Defense Mfg Corp, Philippines

Operating System
- Blowback

Bolt Carrier
- Dedicated bolt and bolt carrier group for the caliber .22LR designed and intended solely for UDMC’s S-22LR, no conversion kits intended in order to eliminate complications associated with “drop-in” kits.

- .22 Long Rifle rimfire. For the Armscor brand, we recommend the 36 grains High Velocity type. Always choose SAAMI standards.

Barrel Type
- Non glare, matte stainless steel barrel, AISI-416R Premium ordnance grade using metal alloy and cylindrical bars from Bergara, Spain.

Barrel Length
- 6.5, 7.5, 10.5, 11.5, 14.5, 16, 18, 20 and 22 inches

Barrel Rifling Twist
- 1:16

Muzzle Velocity
- Depending on barrel length and projectile weight (grains) 1,200 fps (40 grains projectile) up to 1,640 fps (30 grains projectile). Given a choice, go for the “higher Impulse Round” which is Mass multiplied by Velocity.

Maximum Effective Range
- For small game animals and birds, 100 meters up to 150 meters. However, depending on the placement of hits, the caliber .22LR is also dangerous to humans. At 300 meter distance, the projectile would still be retaining a velocity anywhere from 500 to 600 fps.

- 1.3-MOA using match quality ammo at bench rest.

- Single stage, with option for two-stage

Flash Hider
- Optional, with or without flash hider

- 4.5 to 6.0 kgs depending on hand guard and barrel length to be used

- 33 inches (11.5 inch barrel).

Firing Selector
- Safe and Semi-Automatic

Feed System
- 25 rounds Black Dog detachable magazine

Body Color
- Black or Red Anodized