Part 5 - Hand and Rifle Grenades; Chapter 4: Smoke Hand Grenade, W.P. No. 77 Mks I and II (Service)Part 5 - Hand and Rifle Grenades; Chapter 4: Smoke Hand Grenade, W.P., No. 80 Mk I (Service)
BRITISH EXPLOSIVE ORDNANCE
Part 5 - Chapter 4
Smoke, Illuminating, and Incendiary Grenades

Smoke Hand Grenade, No. 79 Mk I (Obsolete) and Mk II (Service)
Data

Over-all length

 7 2/3 in.

Maximum diameter

 4 in.

Total weight

 1 lb. 10 oz., 1 lb. 12 oz., or 1 lb. 6 oz. depending upon filling

Filling and weight

 P.N. 83 (M), 14½ oz.; P.N. 398 or 436, 1 lb. 3 oz.; P.N. 317 or 411, 1 lb. 5 oz.

Fuzing

 No. 247 Mk I, II, and III

Delay

 None

Color

 Light green

Markings

 Standard

Description: This grenade has a cylindrical tin-plate body. The lid is soldered in one or two places to the body, and further secured by adhesive tape. The body is closed by a disc, which is pressed in and fitted with a container for the igniter, while the lid carries a threaded socket for the fuze holder.

The grenade is filled with a smoke mixture, and the igniter container with P.N. 227 composition. A gunpowder-primed cambric disc is fitted above the container to pick up the flash from the fuze and ignite the P.N. 227.

Operation: The adhesive tape and the fuze cap are removed. When the grenade is thrown, the tape unwinds and withdrawn the safety pin. Only the creep spring is then holding the striker away from the primer cap. On impact, the striker is forced against the cap. Smoke emission commences about five seconds later and continues for about 1½ minutes.

Remarks: The Grenade Mk II is similar in construction to the Mk I, but employs a Bouchon type igniter designated Striker Mechanism No. 5.

Figure 245 – Smoke Hand Grenade, No. 79 Mk I

Part 5 - Hand and Rifle Grenades; Chapter 4: Smoke Hand Grenade, W.P. No. 77 Mks I and II (Service)Part 5 - Hand and Rifle Grenades; Chapter 4: Smoke Hand Grenade, W.P., No. 80 Mk I (Service)