(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 as practicable.

(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 cut out.

(12) Recocking the piece without moving bolt in case of mis-fire.

(13) Reasonable certainty of action in automatic loading and ejection.

(14) Comparatively easy action in ejecting by hand in case of mis-fire or jam.

(15) Good balance and shape, adapted to shoulder firing.

(16) Not to be automatic.

(17) Weight not to exceed 11 pounds. This does not include cartridges or bayonet.

THE FOLLOWING FEATURES ARE CONSIDERED DESIRABLE:

(1) In 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 are objectionable.

(2) Vertical 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..

(5) Cartridges 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.

(2) Interchangeability of parts between rifles of the same model.

(3) A bolt in one piece, to a bolt with a separate head.20