Tetryl pellet

A series of supplemental tests were made on chges comprised of a confined cylindrical 3/4-inch diam Tetryl pellet over which a square metal duct or tube was placed, with an oversize 1-5/8-inch diam pellet placed at each end as confinement for the shock tube then the assembly end was initiated. These tests were made to det the fragment pattern effect using the tubes with or without fins. 

MaJfek is similar to the "NOL Gap Test Assembly", previously described in NOL Reports such as ItfavWepsRept 7401 (1961) (Our Ref 48). It is shown here as Fig 4. Tetryl pellets served as a donor, the gap consisted of several cellulose acetate cards 0.25 mm thick, the acceptor was unconfined and the witness plate was of steel. For given donor and gap materials and for fixed geometries of both the donor and the acceptor, the gap thickness which gives the marginal shock strength, called the "gap value"... 

Jaffe et al (Ref 3), in the course of determination of the shock pressure required to initiate detonation of an acceptor in the shock sensitivity test, found that the velocity of the front as sensed by the pressure probe method, falls behind the true velocity of the shock front as the shock is attenuated. It has also been found that the maximum transmitted shock velocity generated by the two Tetryl pellets and measured in Lucite is 4.6mm/frsec. Shock velocities determined by optical method, shown in Table 3, p 25, run between 2.701... 

Fuze, PDM8 is an Army SQ impact fuze used with 4.2-inch chemical cartridges. The complete assembly consists of the fuze proper with an A1 body, its various components, and a seamless steel burster tube. The bursting chge consists of ca 65 g of Tetryl pellets in the burster tube ahd lead cup. The fuze is described in Ref 52k pp 5-12 to 5-15, but a Fig is not given (Also Ref 20a, pp 272-78)... 

Bomb Nose M.T Fuze M129 (Fig 4-24), designed for aerial burst or impact, is used only with the fragmentation (butterfly) bombs assembled in clusters. Its body diam is 1.75-in, overall length 3.0-in, and wt 0.4-lb. It is equipped with primer M41A1, detonator M31, and booster contg Tetryl pellet in a metal cup... 

M31 and Tetryl pellet booster. Designed for use with the fragmentation (butterfly) bomb, it can be set either for "GROUND " action (by impact) or for "AIR" burst, preset for delays 10, 20, 30, 40, 50 or 60 minutes after arming. Arming takes place after 50 -ft of air travel... 

Bomb Burster, AN-M13., designed for use (in conjunction with igniter AN-M9) in incendiary bomb AN-M47A4, consists of a plastic tube 0.45-inches in diam, 36.0-in long, provided at each end with a soft brass cup. It is filled with ca 65 g of TNT and has a Tetryl pellet at each end (Ref 51a, P 5-15)... 

Same size but it was Instantaneous and its Expl Train was MF (Mercuric Fulminate) over Tetryl in an inverted copper cup in upper plug no delay chge Tetryl pellet in lower plug and PA Booster (p 195, Fig 143)... 

Type 4 Gaine for Skipping Bomb. Same size as above with Expl Train Primer compn in upper plug circular BkPdr Delay Train (10 to 11 secs) and Relay in middle plug Primer compn over LA Detonator over Tetryl pellet in lower plug PA Booster (p 197, Fig 145)... 

Booster Sensitivity — minimum total wt of two Tetryl pellets, which produced 50% detons of EDNA of density 1,42 confined in a cartridge... 

The Fulminate detonated the Tetryl pellets from which the. detong wave passed thru the TNT crystals to the cast TNT and so on, with increasing velocity to the main charge of Amatol (Ref 1, pp 162—63)... 

Graphite has found application ini the prepn of Tetryl pellets. In this case, a small quantiry of powdered graphite is mixed with powdered Tetryl and the mass is pelleted. 

Booster Sensitivity Test Min wt of Tetryl pellet at sp gr 1.41 to produce 50% detons is lOOg, with 0.67 wax spacer (Refs 22a St 29b) Brisance Plate dent test, about 9S% of TOT at sp gr 1.5. Lead block crushing — 40g of NGu placed on a block 67mm in diam produced a shortening of 7mm compared with 10.5mm for PA (Ref 6d, p 391 and Refs 22a St 29b)... 

Note Specifications for various adapters are listed in the, Index of Specifications and Standards, Dept of the Army, Washington, DC, vol 2, Oct 1958, pp 1-2 Adapter Boosts , A device which consists of a bushing contg a booster charge, usually tetryl pellets. The adapter-booster is screwed deep into the nose or base plug of a bomb. The device is threaded on its protruding end to seat a standard nose or tail bomb fuze... 

ADT and ADV Propoll ants are described in confidential "Propellant Manual, SPIA/M2, Johns Hopkins Univ, Silver Spring, Maryland(1959)> Unit Nos 394 395 Advance Detonation. In 1941, Woodhead (Ref 1) observed that the velocity of detonation of unconfined columns of pressed tetryl pellets was higher by several hundreds m/sec when there was a continuous cylindrical cavity in the column. Later (Ref 2), the same investigator observed that this phenomenon takes place with HE S more sensitive than TNT (such as gelignite, mixt tetryl/TNT, etc) but is not observed with straight TNT. He also discovered that... 

C.G. Dunkle of Pic Arsn conducted studies of the rate of deton of TNT and, amatols at a d of 1.5 in Shelby steel tubing of 1ID and initiated by pressed tetryl pellets. His data (Ref 70) indicated, by extrapolation, that the rate of deton of AN, under the experimental conditions given, should be 3700 m/sec. The amatols uniformly detond under the conditions mentioned, but the 50/50 amatol consistently failed to deton when extruded,lead tubing was substituted for steel tubing... 

D. Kite, Jr, Safety Hazard Classification of Water-Wet Explosives , PATR 3223 (1965) (AD-460363/5ST) [Table 7 lists deton data for 18 granular w-filled expls loosely packed in Plexiglas tubes of 1.75" ID with wall thicknesses of from 1/8" to 1/4". Expl column lengths were from 10" to 20". Deton was achieved using either 33g Tetryl pellets or 40-grain RDX wafers, electric cap initiated. 

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