Service Acceptance of Smallarms Ammunition

In going through my files I found this document, which probably dates from around 1971 and seems to have formed the basis of an address by Major Louis Yearsley at the Army Rifle Association

THE ACCEPTANCE OF S.A.A. FOR THE SERVICES
1. Definition of S.A.A By calibres this covers:—
a. Pistol: 9mm - .380 in is still current, but no longer in production.
b. Rifle: 7.62mm - .303 in and .30 in are still current, but no longer in production.
c. Large: .5 in for Spotting Rifle and R.M.G-. 20 mm and 30 mm aircraft ammunition are broadly similar, but not classed as S.A.A.
2. Production and Inspection
A continuous process at the rate of approx 3,000,000 per week for 7.62mm ball. Divided into “Lots” or “Dates of Work” of approx 250,000 rds. Empty components accepted, after proof, as “Lots” related to material batches, then passed to filling field. Empty and filled production must meet all requirements of the drawings and specifications, hence 100% inspection of all components and complete rounds on automatic gauging and weighing machines, followed by 100% visual inspection of all complete rounds. Production is the responsibility of the factory (R.O.F. or contractor); Proof and acceptance the responsibility of the Quality Assurance Directorate (weapons).
3. Proof
a. Proof is the verification of the performance required by the specification.
It is the prerogative of the Quality Assurance Directorate (Weapons).
b. Categories of Proof (7.62mm L2A2 Ball)

(1) Assessment Verification of the loadability of the propellant (accepted after proof at the propellant factory) and of the charge required to give the specified ballistics.
(2) Component Proof A representative selection of cases and bullets from run of production of each “Lot”. These are gauged, inspected, loaded, and fired:—
(a) Conditioned at 175°F for 2 hours for case or cap “casualties” in worn service weapons.
(b) At ambient temperature for accuracy and bullet casualties.
(3) Acceptance Proof Approx 600 rds are selected at random from the production run of the “Lot”, inspected, and distributed as follows:—
(a) Break-up (10 rds) Weight of all components, hardness of case, and bullet-pull recorded.
(b) Mercurous Nitrate Test (10 rds) check for stresses in the case which might cause cracks on aging.
(c) Waterproofing (10 rds) Check for leaks at case mouth and cap.
(d) Cap Sensitivity (40 rds) 20 rds for level at which all caps fire, 20 rds for level at which no caps fire.
(e) Velocity & Hangfire (10 rds) Conditioned for 2 hours at 70° F and fired against Standard ammunition. Requirement:— Mean of 2700 ± 30 f.s. observed at 90 ft. from muzzle. Variation of time in bore not to exceed .002 seconds.
(f) Pressure (10 rds) Conditioned for 2 hours at 70°F and fired against Standard Ammunition. Requirement:— Mean not to exceed 21.5 t.s.i. High round not to exceed 23.0 t.s.i.
(g) Accuracy (80 rds) Four x 20 rd. groups at 500 yards. Figure of Merit (Mean radial dispersion around M.P.I.) not to exceed 8 inches.
(h) Casualties (450 rds) Fired in new (1st setting) and worn (2nd setting) service weapons.

Rifle L1A1 1st setting (single shots) 50
Rifle L1A1 2nd setting (single shots) 50
Rifle L1A1 2nd (Rapid) 50
L4 (Bren) 1st (Bursts) 60
L4 (Bren) 2nd (Bursts) 60
L7 (GPMG)1st (Bursts) 90
L7 (GPMG)2nd (Bursts) 90

c. Other Natures (Tracer, Blank, etc.) and calibres
Categories are the same, but detail varies according to the round.
4. Quality Every effort is made to ensure the unquestionable reliability of the ammunition in all respects, in all weapons, and under all conditions, as well as its uniformity of performance over the whole period of production. Manufacturing defects are eliminated to the extent that only very rarely does anything escape the inspection “net”, and. then only through human failure at some stage. Therefore in any incident involving S.A.A. a failure in the ammunition is the least likely cause.