After forging, the projectiles shall be annealed at a temperature of at least 1,200 deg. F.; and after being annealed, tangential test specimens shall be taken from the base or base prolonged of 2 per cent of the projectiles from each lot selected at random by the inspector. The tensile strength of the projectiles in a lot shall not vary more than 20,000 pounds from the highest to the lowest. CHEMICAL TEST (Art. 30, O. D., U.S.A.) A careful and complete chemical analysis shall be made of the metal of each heat from which the projectiles are manufactured under these specifications. TESTS FOR THE DETECTION OF INITIAL STRAINS BORDERING ON RUPTURE (Art. 31, O. D., U.S.A.) After final treatment and before acceptance for the ballistic test, all A.P. shot must be cooled to a temperature of about 40 deg. F., and then suddenly heated by being plunged into a bath of water at a temperature of from 180 deg. F. to 212 deg. F., as the Chief of Ordnance may direct. When thoroughly heated to this temperature each projectile must be plunged, with its axis horizontal, halfway into a bath of water at a temperature not greater than 40 deg. F., and after a brief period shall be turned 180 deg. for a like immersion of the opposite side, after which the projectile shall be removed from the bath. This test shall be made in the presence of the inspector, and an interval of at least three days must elapse between the final treatment and the submission of the projectiles to this test. This test is not required for shell. BALLISTIC TEST (Art. 32, O. D., U.S.A.) Each lot of projectiles shall be subjected to the following ballistic test: After a final treatment and on presentation of the entire lot for the ballistic test, the inspector shall select three projectiles to represent the lot, which shall be finished, inspected and delivered in the same manner as required for the rest of the lot. (a) Armor-piercing shot. Two capped shot, sandloaded to standard weight, shall be fired against a hard-faced Krupp armor plate from 1 to 1-1/2 calibres thick, secured to a timber backing in a manner satisfactory to the Chief of Ordnance, with about the corresponding velocity given by the following table, with the requirement that the shot shall perforate the plate unbroken and then be in condition for effective bursting. If both projectiles fulfill the above test, the lot will be accepted. If, one of the shots fails to pass the test here prescribed, a supplementary test shall be made by firing the third shot under the same conditions as the first two shot; if this passes the test as prescribed above, the lot shall be accepted; if it fails to do this, the lot shall not be accepted.