Semi-Automatic and Automatic Military Rifles –
A little history. By Ted Burris  Copyright © USRNSF 2009

The ‘United States Rifle, Caliber .30 M1’ (Caliber .30-06) (European 7.62x63)

or as it is better known the M1 Garand (named after its creator John Cantius Garand) was the first
semi-automatic rifle to be generally issued to the infantry of any nation.  In 1936 it officially replaced the M1903 Springfield as the standard service rifle of the United States Armed Forces and was subsequently replaced by the selective fire M14 in 1957.  However the M1 continued to be used in large numbers until 1963 and to a lesser degree until 1966.

The M1 Garand was the designated service rifle of the US Military during WWII and the Korean War. It was designed for semi-automatic fire using a spring steel “clip” containing 8 rounds of 30-06 or Caliber .30  ammunition.

This is where the term “clip” originated.  Other rifles used detachable or fixed magazines.

The U.S. Army fielded accurized sniper M1 Rifles even into the Vietnam War even though by that time the M1 Garand had been supplanted by the M14 and later by the M16.

Criticisms of the M1 Garand where its weight, limited ammunition supply, the fact that single round loading was difficult or impossible and that the spent clip was ejected automatically making a distinctive sound that could be fatal in close quarter or sniper operations.

As a supplement to the Garand the M1 Carbine was developed.

The M1 Carbine – (Caliber .30 Carbine)

Up until very recently the M1 Carbine had the distinction of being the most mass produced U.S. service rifle in history.  The M1 Carbine was half the weight of the M1 Garand and used a removable box magazine.  It utilized the .30 Cal Carbine cartridge generally considered effective to 300 yards verses 1000 yards or more for the M1 Garand and its .30-06 cartridge.
Initially the M1 Carbine was intended to have select fire capability, but the decision was made to put the M1 Carbine into production without this feature.

A variant of the M1 Carbine known as the M1A1(Shown Below) incorporated a folding stock and was issued to paratroopers and aviators.

Full Auto Fire Mode was incorporated into an upgrade known as the M2 Carbine introduced in 1944.

Parts kits were created to update the M1 Carbine to the M2 Carbine. An update to the M2 Carbine was known as the M3 Carbine and included the "M1 Sniper scope". An infrared night scope and illuminator shown below.

This configuration was first used in combat during the invasion of Okinawa and was usually deployed to a 3 man team since what this picture does not show is the rather large and heavy battery box that had to connect to the weapon system to make all the technology function. Still for the first time US Troops had night vision. It is estimated that nearly 1/3rd of all rifle inflicted Japanese causalties in Okinawa were the result of this configuration and the teams who utilized it.

In normal configuration the reduced weight and lighter ammo made the M1 Carbine and its variants good choices for many circumstances where the M1 Garand was more weapon than was needed. But the M1 Carbine did not replace the M1 Garand it was merely a supplement to it. The M1 Garand was replaced as the standard battle rifle in 1957 by the M14

The M14 – (7.62 NATO)

The M14 used a 20 round removable box magazine and double lug receiver and was originally designed for fully automatic fire.  It was quickly discovered that the 7.62 NATO cartridge combined with the high cyclic rate of the M14 made the weapon uncontrollable in full auto mode and most of these weapons had their selective fire capability removed. The M14 remained a very suitable semi-automatic sniper rifle and is still deployed today in some cases for this purpose where its heavier 30 caliber bullet can out perform the .223 of today’s M16.

Variants of the M14 include the M21 and M25  (M21 Shown Below)

Civilian models of the M14 include the Chinese “Polytech” and American M1A.

Civilian Model M14 aka The M1A  –

The M1A resembles the M14 however there are some differences especially in rifles manufactured after 1991. Obviously the M1A was created for the civilian market and therefore lacks the select fire switch and the stock cut-out required for it.  M1A’s typically do not have the height adjustable stock plate on the rear stock although some after-market stocks have been created that include this feature. Springfield dropped the caliber designation from the rear of the rifle.  Additionally the M14 receiver was drop forged while the M1A is cast. This creates a significantly different sound when fired. In response to the 1994 assault weapons ban newer M1A’s are produced without the bayonet lug.
When it comes to the disassembly there are minor differences as well.  With the M14 you could simply remove the connector and the operating rod slides out where as the M1A commonly uses a method known as “twist and pray” to remove the operating rod. The M14 was replaced by the M16.

The M16 ---

(Top to bottom -  M16A1, M16A2, M4, M16A4)

The M16 fires the 5.56x39 NATO cartridge and is typically supplied with 20 or 30 round removable box magazine. Making its debut in the Vietnam war the M16 was an instant success.  In Vietnam most fire fights took place at 50 yards or less where the extra weight and recoil of the M14 proved inefficient and the added range of the 7.62 cartridge was unnecessary.  The M16’s 5.56 cartridge and lighter weight meant a soldier could carry more ammunition. The M16 had full auto fire capability but Army testing determined that in that mode accuracy suffered after 3 rounds. The M16A2 upgrade changed the triangular fore grip and changed full auto to a burst fire mode of 3 rounds to make the weapon more controllable and conserve ammunition. Later upgrades included flat top receivers with removable carry handles and quad rail systems for adding accessories.
Civilian models were produced as semi-automatic and some companies have even made bolt action versions. The typical civilian model is designated M-15, AR-15, or CAR-15 and some models have been created to fire other calibers like the 7.62 NATO of the past. Some examples of these are Armalites AR-10, and Knight Industries SR-25 Stoner.

Plans are underway for the next shoulder fired battle rifle.  The unfortunate implementation of the 5.56 round has left our troops wanting a more powerful weapon and that will likely play a role in the choice of the next shoulder fired battle rifle. 

What will be the M16’s replacement?  We will have to wait and see but here are some of the competitors.

The Heckler and Koch XM8 (5.56x45)

The FN F2000 (5.56x39)

FN SCAR (SCAR-L 5.56x45, SCAR-H 7.62x51)