(1) A simple,
strong, and durable mechanism, composed of as few parts as possible, readily
dismounted and mounted with as few tools as practicable, and assembled with the
minimum number of springs, screws, or pins. The mechanism should be as compact
(2) The caliber
should be about 0.30.
(3) The magazine
or other attachment for holding cartridges to have a capacity of not less than
eight. The Department will, however, consider a design submitted with a view
of modifying or adapting the present service rifle to a semi-automatic rifle.,
in which case a capacity of 5 cartridges in the magazine will be sufficient.
(4) The weight
of the bullet to be not less than 150 grains.
(5) The initial
velocity to be not less than 2650 feet per second.
(6) The bolt
to be locked or in its firing position before the firing mechanism can be operated
(7) The breech-block
to remain open when the last cartridge in the magazine has been fired.
(8) The trigger
pull (measured at middle point of bow or trigger), not to be less than three
nor more than 4 ½ pounds.
(9) A magazine
cut-off, and a safety or locking device permitting arm to be carried cocked and
with cartridge in barrel without danger.
(10) A minimum
limit of fire, considering time for motion of parts, for reloading, etc., of
90 rounds per minute, when firing as rapidly as possible.
(11) (a) must
be capable of use as a single loading arm, magazine in reserve. (b) Must be capable
of use as a magazine rifle, fed by hand, with semi-automatic feature entirely
the piece without moving bolt in case of mis-fire.
certainty of action in automatic loading and ejection.
easy action in ejecting by hand in case of mis-fire or jam.
balance and shape, adapted to shoulder firing.
(16) Not to
not to exceed 11 pounds. This does not include cartridges or bayonet.
THE FOLLOWING FEATURES ARE CONSIDERED DESIRABLE:
the construction, such separation of parts that each part may be readily replaced
in case of repair. Parts riveted together or more or less permanently joined
in preference to side ejection of cartridge case.
(3) No special
tools for dismounting or assembling.
(4) An automatic
indicator of the number of cartridges in the magazine, the mechanism to be so
arranged as to prevent the entrance of dust, etc..
of length over all not more than three inches. The use of shorter cartridges
will allow of reproduction in length of receiver, and will facilitate feeding.
This is considered a very desirable feature.
THE FOLLOWING FEATURES ARE PREFERABLE:
(1) A bolt
securely locked to the barrel until the bullet has left the bore.
of parts between rifles of the same model.
(3) A bolt in one piece, to a bolt with a separate head.20
S.A. 109/g, O.O. 38351-75,
3rd Ind., April 5, 1909