From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
The trials of the 40 mm Aircraft Gun No. 11239 at Pendine.
| Identifier | ExFiles\Box 176\1\ img190 | |
| Date | 20th May 1941 | |
| Re-Sg.{Arthur F. Sidgreaves - MD} from Ve. S. to Rm.{William Robotham - Chief Engineer} HRO; Ve.7/CB.20.5.41. TRIALS OF 40 mm. AIRCRAFT GUN No. 11239 AT PENDINE ON THE 5th to 15th May. The trial, which was called for by the Director of Armament Development, was carried out under the direction of the Deputy Superintendant, Small Arms Experimental Establishment, Pendine, Wing Commander Bullock. Rolls-Royce were represented by Ve/NP. for the first part of the trial and Ve/FH. for the second part. The gun gave a reasonable performance demonstrating high rate of fire with good accuracy. There were certain stoppages and failures, all of which can be overcome by fairly simple modifications. The ammunition used was 40 mm. A/S, filled 1950 grains H.S.C.T. The programme of firing laid down was as follows :- (1) 10 rounds single shot for accuracy - 1000 yards. (2) 10 rounds automatic for accuracy - 300 yards. (3) 10 rounds observed velocity at 90 feet taken during (1) (4) 10 rounds at 80° elevation. (5) 10 rounds at 80° depression. (6) 10 rounds at 80° elevation after 5 hour soak at -10° (gun and ammunition) (7) 10 rounds at 80° depression as (6) (8) 10 rounds sand test horizontal. During the trial, the above programme was exceeded as it was thought desirable to give the gun a more arduous test to show up any weaknesses at an early stage. In consequence, a total of 180 rounds were fired as follows :- Accuracy test - single shot. 10 rounds. Accuracy test - automatic. 21 " continued. | ||