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View Full Version : The M16: What could've been...



stanc
10-21-2009, 01:02 AM
Might the performance failures attributed to the 5.56 NATO round have been avoided?

From Frankford Arsenal's last commander:

I do think the 5.56mm cartridge needs to be replaced--in my opinion, the 5.56mm is under-powered for Urban and long range combat (over 300 meters) and is very difficult to manufacture and has marginal performance from an exterior ballistic standpoint. Now as to what should replace it, I would think some round in the Cal..25 range that could be retro-fitted to existing weapons should be considered. Strange as it seems, Col. Studler at OCO in 1958-59 suggested to Stoner that the AR-15 should be increased in caliber to .258--this round called the "6.35mm Long" was tested at Ft. Benning in 1959 with good results.
Because of the OAL of the 6.35mm Long, that cartridge would've necessitated a complete redesign of the AR15. That wouldn't have been a great problem in 1959, but is hardly feasible for retrofitting current 5.56mm weapons. However, the shorter 6.35x48mm (http://www.ammo-one.com/6-35x48mmFA59.html) -- which was also developed in the late 1950s -- has OAL the same as 5.56x45mm, making it usable in the M4/M16 by swapping barrel, bolt, and magazine.

Interestingly, both of those 6.35mm rounds were based on the .25 Remington, which has the same basic case as the .30 Remington that was used to develop 6.8 SPC. If the Army had elected to chamber the M16 in 6.35mm, we might've had 6.8 SPC created two or three decades earlier than it was.

OTOH, there might never had been a perceived need to develop 6.8 SPC... :a08:

Clint
10-21-2009, 07:01 AM
Interesting. Check out that claimed performance.


The cartridge was one verison based on the .25 Remington case, the (FA-T116) measures 6.35x48mm and loaded with one 70 grain
which had a velocity of 3,345 feet per second.

marinesg1012
10-21-2009, 09:00 AM
Interesting cartridge, to bad it didnt take off, IMHO anything would of been better then the 556.....

Equalizer_2
10-22-2009, 11:11 PM
I wouldn't say anything, the Brits came up with the 4.85mm British with a 56 gr bullet at about 3120 fps and the Germans came up with something similar. These were entered in the NATO trials in 1977.

DocGKR
10-23-2009, 02:27 AM
The shear number of gross failures by the U.S. Army Ordnance bureaucracy staggers the imagination. If .276 Pederson, the British post WWII .270/.280 cartridge, the Frankford 6.35x48mm, or the 6 mm SAW had been actually adopted, there would have been no need for a 5.56 mm replacement like 6.8 mm, because we would already have had an intermediate caliber cartridge and 5.56 mm would likely never have been accepted as the standard rifle and LMG cartridge...

Bigdog923
10-25-2009, 01:07 AM
Thanks for posting the info Doc

M995
01-25-2010, 11:19 PM
I think that an AR-18 chambered for 6.35mm long should have been the successor to the M14 instead of the 5.56mm M16A1. That means we might not have needed to develop either the 6.8mm SPC or the FN SCAR.

Drifter
01-25-2010, 11:38 PM
Didn't know that about the AR...

IIRC, the .276 Pederson was the among the early cartridges for the Garand (predecessor of the M14), but with so much .30 ammo already on hand for the military's M1903 Springfield rifles (.30-06), the final design was steered to the larger caliber.

Seems that a middle caliber has been recongnized more than once as potentially optimum for military use, but never made it far past the drawing board...