On November 15, 2011 while excavating the site of the World War II crash of a British Spitfire fighter in an Irish peat bog, six intact Browning Mk 2 machine-guns were found and recovered intact. One was cleaned-up and test fired, after more than 65 years submerged in a bog - it still worked.
Peat bogs have a remarkable ability to preserve organic and inorganic material, and in this case also cushioned the impact (at 500 kilometers an hour) of the Spitfire as it hit the side of the hill. This sturdy machine-gun was designed by John Browning, one of the most successful firearm designers of the late 19th and early 20th centuries. While aircraft use of the M2 lasted about half a century (being replaced by 20mm and larger caliber autocannon), ground troops continue to use it as the M2 ("Ma Deuce"). The M2 has proved so effective, that it's become too good to replace.
Three years ago, the U.S. Army gave up on getting a replacement for the nearly century old M2 machine-gun, at least not anytime soon. However, many of the current ones were wearing out, so the army began replacing over 80 percent of its 36,600 M2 machine-guns, a process expected to take five years, with new M2s. Numerous efforts to develop a replacement for the M2 have failed so far.
Originally, the M2 replacement was going to be the M-307, which was designed so it could fire either the computer controlled 25mm "smart shell" of the XM-25, or (by changing the barrel and receiver), 12.7mm caliber ammo. But it was felt that a straight replacement for the M-2 was needed quickly. The original plan was for the troops to begin getting the XM312 in 2008, or sooner. Didn't happen.
The M-2, nicknamed "Ma Deuce" by the troops, has been around so long because it was very good at what it did. Accurate, reliable, rugged and easy to use, many of the M-2s currently in use are decades old, and finally wearing out. The army didn't want to build new ones, and wasn't sure it could do without the venerable, and very useful, Ma Deuce. So it tried to develop a new .50 caliber machine-gun (the XM312). The XM312 weighs 16.4 kg (36 pounds), compared to 38.2 kg (84 pounds) for the M-2, even with the addition of the electronic fire control stuff from the XM307.
The fire control system, especially the range finder, makes the XM312 much more accurate with first shot hits. American troops testing the XM312 also reacted favorably to the lighter weight and fire control electronics. But the lower rate-of-fire on the XM-312 was a deal killer to the many troops who had used the M2 in combat recently.
So barring a sudden new development in firearms or ammunition technology the M2 will likely continue serving past 100 years and quite possibly a few decades beyond that. An amazing achievement for any design, much less one that was designed during WWI by a man born before the Civil War.
While in Iraq my Cavalry Troop had 12 HMMWV's and six were armed with the venerable Ma Deuce, and when Ma Deuce started barking people got scarce real fast. There is just something about that sound when she opens up, that low thumping sound that really makes you feel like everything is going to be OK. Not exactly Warhammer history - but damn cool and kinda personal to me as well.