America and Britain – two nations
separated by a common cartridge* or
how 7.62x51mm became the NATO
standard
* With apologies to Oscar Wilde, Bernard
Shaw and others?
Dave Sutton, Phoenixville, PA
natodave@verizon.net
The Western Allies at the End of WWII
• Basic infantry weapons
– US
•
M1 Garand firing .30-06 cartridge
• Heavy
• Semi-automatic
– UK
•
Lee Enfield firing .303 British
• Heavy
• Bolt action
US – Beyond the Garand
• Greater firepower, light weight
– Convinced that this had to include a cartridge with comparable
ballistics to the .30-06 i.e. able to inflict a fatal wound at 2000 yards
• Desire for a new and improved cartridge
– Use of improved propellants from du Pont allowed a shorter cartridge
case with similar ballistics to .30-06
•
Shorter case
• Shorter breach = lighter rifle
• Less materials for manufacture
• More cartridges per unit weight i.e. soldiers can carry more
UK – Beyond the Lee Enfield
• Need for a selective fire rifle
• Recognition that the .303 cartridge was overkill at normal
combat ranges
– Willing to accept a less powerful cartridge using a bullet smaller than
0.303
– Small Arms Ideal Caliber panel established in 1945
• Aim for lightest rifle and cartridge acceptable for combat out
to 600 yards
US Response
• March 1944
– Initial request for shortened .30 cal cartridge based on 300 Savage
.30.06 - case length, 2.49”
.300 Savage - case length, 1.87”
• Mid 1944 to early 1945
– Testing of .300 Savage cartridges loaded with M2 bullets
• January 1945
– Request for development of T65 cartridge
US T65 Series
No known
examples
Case type 30-06
.300 Savage
T65
FAT1
FAT1E1
1944
1945-1947 1947-1948 1948-1949
Commercial
30-06 head, decreased
body taper, 1.871” case
Increased neck length
and extractor grove
width, 1.951” case
FAT1E2
???
Increased rim thickness,
decreased extractor
groove width, 1.951” case
Increased body taper, decrease
shoulder diameter and angle,
1.951” case
FAT1E3
1950-1954
Increased body taper, case
length, base to shoulder,
shoulder diameter, shoulder
angle and neck length,
2.015” case
UK Response
• Small Arms Ideal Caliber Panel
– Formed 1945
•
Extensive theoretical and experimental work
– Final Report March 1947
•
The Choice of a Standard Round for Small Arms
–
–
Caliber of about 0.27” if tungsten core unacceptable
Caliber down to 0.25” if tungsten core acceptable
– Two cartridge designs approved
•
•
.280 - mid-1947
.270 - October 1947
.303 British - case length, 2.21”
.270 - case length, 1.81”
.280 - case length, 1.70”
UK 7mm Series
280
Development of the
.270 cartridge ceased
in 1948 and future
work focused on the
.280 and .280/30
270
280
Photo from Tony Edwards
280/30
Extractor groove, rim
and case head
diameter modified to
US .30 cal dimensions
The Political Scenario
• Change in British Government from Conservative to Labour in
1945
– US fears of Communist influence
• Talks initiated on 1946/1947 between US, Britain and Canada
regarding standardization of war materials including SAA
– Apparent exclusion of the Soviet Union seen as the start of an alliance
against Russia by certain factions in the Labour party who became
openly critical of standardization
• Creation of North Atlantic Treaty Organization
(NATO) in 1949 to counter the military threat
of the USSR
US-British Interactions
• 1947 First face to face meeting
– US Ordnance flatly refused to consider the UK .280 cartridge on the
grounds that certain bullet types could not be developed
– The British learned about the .30 cal T65 cartridge for the first time
•
Convinced that the best light rifle could not be designed around the T65
cartridge
• 1947-1949 Miniature arms race between US and UK
– Britain suggests that tests of the two nations cartridges should be
scheduled – set for early 1950
• 1949 Early test results of the US T25 rifle are encouraging
– Britain, fearful that large-scale procurement of the T25 could kill off
consideration of any British designs, requests that that the
comparative trials now cover both rifle and cartridge
1950 Trials
• Aberdeen Proving Ground/Fort Benning
– Head to head trials of US and British rifles that included evaluation of
ammunition
•
Rifles
US Springfield T27
•
UK EM-2
Belgium FN FAL
Ammunition
– US - .30 cal (FATE1/FAT1 cases)
– UK/Belgium - .280
• Trials took place over 6 months
– Conducted with great fairness ensuring rifles and ammunition were
compared under as near identical conditions as possible
1950 Trials - Ammunition
US .30 cal
British .280
1950 Trials – Results
.30 T65
Accuracy

Trajectory

Penetration

.280
API ignition

Tracer/observation function

Ballistic coefficient

• Neither the rifles nor the ammunition was suitable for adoption
without further modification
• Recommendation that ammunition be perfected prior to
designing the weapon
• Need for agreement on a common cartridge before any further
weapon comparison trials take place
US Army Issues with the .280 Cartridge
• Trajectory
– Unacceptable “safety zone”
Safety zone
Bullet height (inches)
100
280 Ball
T104
30-06 M2
6'
80
60
40
20
0
-20
0
100
200
300
400
500
600
700
Range (yards)
• Performance in arctic conditions
– Unacceptable muzzle velocity under temperate conditions would lead
to serious problems at sub-zero temperatures
• Difficulty in developing satisfactory special purpose rounds
(tracer, AP, API etc)
Beyond the 1950 Trials
• Although the US trials effectively eliminated the .280 cartridge
from further serious consideration, efforts were made to keep
it alive
– April 1951 - UK army adopts the EM-2 loaded with an improved
.280/30 cartridge (7mm Mk1z)
• US Ordnance
– Protracted campaign to ensure demise of a 7mm cartridge with goal of
ensuring that NATO adopt the T65 cartridge
• Reality begins to sink in
– UK and Belgium redesign EM-2 and FAL respectively for the US .30 cal
cartridge
–
Feasible for the FAL, but not EM-2
The Path to NATO Standardization
• Mid 1951
– Joint meeting between US, UK, Canada and France to discuss SAA
standardization
•
•
•
•
•
UK tries without success to sell the 7mm series
US continue to hold to their decision to adopt the T65 cartridge
France favor the T65 cartridges since the new 7.5mm semi-automatic rifle
could more readily converted to the US cartridge
Canada look for standardization of one caliber whatever it is
This meeting effectively sounded the death knell for the .280/30 cartridge
• Sept 1951
– NATO standing group agrees on set of military characteristics of
required performance for any new SAA
•
Tests showed UK’s 7mm Mk1z fell well short
The Path to NATO Standardization II
• Late 1951
– The US Army officially rejects the .280 cartridge
•
“The Army is firmly opposed to the adoption of any less effective smaller
caliber cartridge for use in either its present rifle or in new weapons”
– New UK government reverse earlier decision to adopt EM-2 and the
7mm Mk1z cartridge
•
•
•
•
Reflected the reality of post-WWII Europe
UK SA industry not strong or big enough to go it alone
Need for cooperation and standardization in light of cold war
Need for US help in rebuilding Europe
• The UK’s action effectively guaranteed the adoption of the .30
cal light rifle cartridge as the NATO standard
The Path to NATO Standardization III
• 1952 onwards
– 1952 UK, Belgium and Canada form the Small Arms Development
Committee (later referred to as the BBC)
•
Aim is to develop a 7mm cartridge acceptable to NATO
7mm
Optimum
7mm
High Velocity
7mm
Compromise
7mm 2nd
Optimum
The Path to NATO Standardization IV
• 1952 onwards
– BBC holds a series of trials comparing the various 7mm
cartridges with .30 cal cartridges
•
Final trials held in mid-1953 compare various .30 cal loads against the 7mm
2nd optimum cartridge
– The US continues on with the T65 series regardless
•
T25 rifle dropped and replaced by the T44 (Adopted in 1957 as the M14)
Springfield T44E4
– Sept 1953 BBC recommends selection of a .30 cal bullet in the FAT1E3
case
NATO Standardization
• Dec 1953
– NATO announces the T65E3 cartridge as the common NATO cartridge
• Feb 1954
– Specifications agreed (finally ratified in 1957)
• Aug 1954
– Formal adoption of the T65E3 cartridge as
•
•
Case, NATO Cal. 7.62mm
Cartridge, Cal. 7.62mm, NATO, [type]
– Belgium is the first country to use the new NATO design mark USA
UK
Belgium
Canada
France
7.62mm NATO cartridges (US)
Regular
Ball,
M59, M80
Tracer,
M62
OHF
AP,
M61
Dummy,
M63
HPT,
M60
Blank,
M82
Grenade,
M64
7.62x51mm Retrospective
• Since its adoption in 1954
– Manufactured and/or used by 60+ countries
– Replaced by 5.56x45mm as the main infantry rifle cartridge, but
remains in use for
•
•
GPMG
Intermediate range sniper cartridge
• Introduced to the civilian community by Winchester in 1952
as the 308 Winchester
– Still in production over 50 years later
•
•
•
Excellent hunting cartridge
Excellent accuracy
Law enforcement role