In 1916, Frank F. Burton began developing the rifle, creating a single example. The most prominent feature of the Burton LMR is the twin 20-round
box magazines positioned 30° left and right from the rifle's line of sight. The magazines have two locking catches on the front, and one over-travel stop on the back, that allow one magazine to feed whilst placing the other on standby. The only extant example (now at the
Cody Firearms Museum) of the LMR has two interchangeable barrels: ground and airborne. The infantry barrel is equipped with a bayonet lug. Both barrels feature
cooling fins similar to later weapons such as the
Thompson 1928. The primary trigger is housed within the trigger guard, and is used to fire in semi-automatic. The LMR utilises an additional trigger located under the trigger guard as the select-fire mechanism. Squeezing the trigger causes the sear to be locked in place, allowing the bolt to return for fully-automatic fire. It features an open bolt with a simple blowback operation to cycle new rounds and eject spent casings downward. The charging handle is also shaped like a trigger and is located on the bottom of the receiver.
Ammunition The .345 Winchester Self-Loading is a straight walled
rimless,
centerfire intermediate cartridge created in 1917 by Frank Burton for the light machine rifle. The cartridge was created by modifying
.351 Winchester Self-Loading shells and fitting an 8.8mm
spitzer bullet. It is speculated that the bullet is large enough to house an
incendiary component, however the original ammunition cards do not specify an incendiary capability. ==In popular culture==