|
|
| BRITISH EXPLOSIVE ORDNANCE |
| Part 1 - Chapter 6 |
| Semi-Armor-Piercing and Armor-Piercing Bombs |
|
S.A.P. 250-lb., Mks II and III (Obsolete), and Mks IIC, IIIC, and V (Service) |
| Data |
|
Fuzing |
Mks II-IV, Tail Fuze No. 30; Mk V, Tail Pistols No. 28 or No. 30 |
|
Color markings |
Dark green over-all; ½-in. white band 3 in. from nose; ½-in. red band 3½ in from nose; 1-in. light green band 6.5 in. from nose |
|
Tail No. |
Mks II and III, No. 1 Mk I; Mk V, No. 10 Mk I |
|
Over-all length |
49 in. |
|
Body length |
31.5 in. |
|
Body diameter |
9.2 in. |
|
Wall thickness |
0.91 to 0.99 in at maximum diameter and 0.61 to 0.69 in at minimum thickness beginning 16.8 in. abaft nose |
|
Tail length |
No. 10 Mk I and No. 5 Mk I, 18 in. |
|
Tail width |
9.2 in. |
|
Total weight |
245 lb. |
|
Charge/weight ratio |
17% |
|
Body Construction: The Mk V body is forged steel with a pointed nose and an open base, threaded internally to receive the exploder container, which is cemented in positi-on. The base of the body is threaded externally to receive a tail adapter, which is in form of a coned ring with four equi-spaced slots to receive the spring clips of the tail. Earlier marks were similar to the Mk V, with slight variations in the tail adapter. |
|
Tail Construction: The Tail No. 10 Mk I has a tail cone with a cylindrical strut atta-ched by four fins. It is attached to the bomb body by four spring clips. The arming spind-le engages the fork in the tail pistol. The Tail No. 1 Mk I, used on Bombs Mk II and III has no spring clips, while the Tail No. 3 Mk I used on Bombs Mk IIC, Mk IIIC, does have spring clips. |
|
Suspension: A single suspension lug is secured to the body by four screws. |
|
Explosive Components |
|
Detonator – (See Part 2, chap. 4, Detonators.) |
|
Exploders – C.E. pellet in Mks II - IV, and H.E. in the Mk V. On the Mk V, there is a separate layer of TNT around the exploder. |
|
Filling – Mk V, 40.5 lb. TNT/Beeswax; Mks II - IV, 42.5 lb. TNT. |
|
Remarks: The Tail Fuze No. 30 has left-hand threads on the securing ring. Use of the Tail Pistol No. 37 is unlikely. |
|
Tail fins are usually painted red when the Time Pistol No. 37 is used. |
|
Any mark may be found fitted with a copper driving band for proof firing from the B.L. 9.2-in. howitzer. |
|
|
|
Figure 25 – S.A.P. 250-lb. Bomb Mk V |
|
|
