MCR Series AR type Rifles for the 21st Century

At Cobb we are proud to introduce the worlds first true multi-caliber AR type rifle for the 21st

century. Designed for the Special Operations SCAR rifle requirement to USSOCOM.

The MCR (Multi-Caliber-Rifle)(Patent-Pending) series rifles are chambered in a long list of calibers,

from 9MM to 338 Lapua.

MCR 400 Rifle shown with optional equipment

MCR-400 Semi-Automatic Rifle Caliber 338 Lapua Magnum (8.6x70mm)

Video of the rifle being fired


-Lothar-Walther 30″ Stainless Steel match barrel with 1 in 10 twist (Sub-MOA)

-Accuracy International 5 round detachable magazine

-Over all length 56″

-Weight 18 lbs

-AR15 fire control parts

-AR15 Butt stock and pistol grip

-MIL-STD 1913 free floated rail system with full lenght rail on the top end

-Semi-Automatic gas operated

-Hard case with wheels

-Harris Bipod

-Multi caliber lower capable of switching to 7.62mm and 5.56mm calibers with upper and magazine well change in less then 1 minute without any tools

New for 2007 is our U.R.S. (Universal Rail System)

It can be installed on our MCR rifles or these other .308 caliber rifles, Armalite AR10’s, KAC SR-25 and DPMS LR308.

MCR 300 Rifle shown with optional Dark Earth finish and Command Arms SRS stock

MCR stands for Multi-Caliber-Rifle and it is built on the AR type design. MCR Semi-Automatic rifles come in

four different models which interchange with each other from one series to the next. To change calibers

for example from a .223 (MCR100) to .308 (MCR200) you simply change the upper receiver and magazine module.

RSR Group Exclusive MCR rifles and caliber conversion kits

COBMCR3006AN – 30.06 100th Anniversary edition MCR 300, ONLY 100 units made. These rifles will have the anniversary logo engraved on the rifle, free floated Quad MIL-STD 1913 rail, 2-20rd modified BAR 1918 magazines, Otis cleaning kit, Harris bipod, Lothar-Walther 24″ 1 in 10 twist barrel, Vltor stock, ERGO tactical grip and Hard case with wheels.

COBMCR3006PK – This package includes anniversary edition package plus Leupold Mark 4 3.5-10x40mm scope and rings.

COBCONV308 – The .308 conversion kit with DPMS 20rd magazine and 24″ Stainless Steel Match Lothar-Walther barrel, now in-stock.

COBMCR308 – MCR 200 in .308 with DPMS 20rd magazine, MIL-STD 1913 rail, 24″ Stainless Steel Match Lothar-Walther barrel.

Several caliber conversions – 338 Federal, 8MM, 338-06, 25-06, 270 Winchester, 280 Remington can be used on the MCR series rifles.

MCR Series Rifle Specifications:

-Upper/Lower receivers and magazine module made out of T6-6061aircraft aluminum.

-Semi-Automatic AR type gas operation.

-Free floated Lothar Walther barrel available in different lenghts.

-MIL STD-1913 rail machined on the upper receiver.

-AR type pistol grip and butt stock.

-AR type trigger group parts that interchange with standard AR’s.

-Rifle weight depending on calibers from 8 lbs to 16 lbs.

Rifle comes with standard hand guard, stock and grip.

Command Arms SRS fully adjustable stock, fits any AR15A2/SR25/M16 rifle

Also available with DPMS/KAC SR25 magazine well.

MCR-200 Series Rifle Calibers: .308/7.62mm ~ 338 Federal

MCR 300 magazine well with 100th anniversary of the 30.06 cartridge logo

To celebrate the 100 years of the 30.06 cartridge we have made 100 rifles with the 100-year logo on the rifle. This will be a limited edition rifle with the optional MoD-0 kit which includes the Leupold Mark 4 scope, and NFA sound suppressor with the 100-year logo.

All MoD-0 kits come with hard-case, 2-20round magazines, bipod, Otis cleaning kit, Leupold Tactical Mark 4 LR/T scope and NFA sound suppressor. Available now!