The M85 tank machine gun

US Ordnance started looking for a replacement for the Browning M2 50 cal m/g near the end of the Korean War. By 1959, they had the T175E2 adopted as the M85 and used in the M60 MBT. They thought the Browning which dated to the end of the WW1 period should be replaced.

The new M85 had the following improvements over the Browning M2: 1) 20lbs lighter. 2) 11 inches shorter. 3)quick change barrel 4) fired from an open bolt with two rates of fire. 5) used a push out link on the cartridges

During the service life of the M85 it became known as unreliable had extraction issues and jamming caused by the links. The problems with the M85 were never resolved

my photos show the difference in the 50 cal links and the M85 schematicAttachment 135322Attachment 135323Attachment 135324 .

I'll have to keep a lookout for some of those links...you don't see them here of course. They'll be specially hard to find after all this time.