Bangalore Torpedoes Detonating Cables Demolition Hoses and Demolition Snakes These

are long demolition devices which are intended chiefly for clearing mine fields and for blasting passages through wire entanglements. There are also some other uses indicated below

Bangalore torpedoes exist in several modifications. The std US device, M1A2 which was used successfully during WWII, consists of 10 loading assemblies, 10 connecting sleeves and 1 nose sleeve. The loading assembly consists of a steel tube 5 ft long and 2 1/8 in diam, filled with 7.61bs of 80/20 amatol (or other solid HE) and topped off by 4" of TNT(ca 1.4 lbs) at each end. Each end is capped and grooved and cont ains a fuze well to accomodate a detonator, primacord, or a blasting cap(such as Corps of Engineers Cap, called now Cap, Blasting Special, described in Ref 14> or a commercial one not smaller than No 8) attached to any of the std firing devices. Initiation may also be accomplished by a detonator or four turns of primacord wrapped around one end of the tube. The torpedo may be used as a single tube or several tubes(called loading assemblies) may be fastened together by means of connecting sleeves as shown on Fig 222,p 37 in Ref 2 and Fig 192, p 266 in Ref 5. A nose sleeve with a rounded point is provided for ease in pushing the torpedo through obstacles(Refs 2,3 & 5) A short length of bangalore torpedo can be used as an antitank(A/T) or an antipersonnel (A/P) mine or as a booby trap. It was also used, according to Ball(Ref 4), by US troops for destruction of pill boxes during the attack on the Siegfried Line in March 16, 1945. For this, a 5-ft length of bangalore torpedo, equipped with a pull fuze, was dropped inside a narrow vent pipe sticking out the top of each Ger pill box. This was the idea of an unknown Amer soldier and the device was fired after the bazooka shot and the pole charge failed to penetrate completely through the vent

A more recent US bangalore totpedo is the M1A2. It is described in conf Ref 6, but in unclassified Ref 12 it is mentioned that its chge is 9.5 lbs of Comp B or Comp A-3. The US Military specification requirements are in Ref 13 Detonating Cable can be used for the same purposes as a bangalore torpedo. A std US device Ml for clearing narrow lanes in A/P mine fields consists of a nylon-covered cable(also called rope), 170ft long and ca 1 in diam, which contains 46 lbs of oil-soaked PETN(regular detonating cord should not be used as a substitute). The cable consists of 19 strands of special detonating cord, each contg ca 100 grains PETN per ft. One end of the cable(which contains a booster chge and a threaded cap well for inserting a 15-second delay detonator for exploding the cable) is anchored to a stake driven into the ground, while the other end is projected across the mine field by a JATO unit. The cable is then exploded by the detonator at the anchored end(Ref 5,pp 2878). In the older device, which was used during WII, the cable(rope) consisted of 13 strands of detonating cor;d 215ft long. In prepg the cable, the 13 strands(cords) were held by several men and wrapped with twine and tape. One end of the cable was attached to the ground and provided with US Army Special Nonelectric Blasting Cap (described in Ref 14), a 15" length of time fuse and a lighter. The other end of the cable intended to be projected across a mine field was attached by means of manila rope to the body of a 105mm base-ejection smoke shell(M84), modified to function as a rocket. For this, the empty shell with fuze deactivated was placed upside down and, after removing the base-plate, about 1 of earth dirt was temped in the nose of the shell to seal off the hole leading to the fuze. This was followed by ca 150g of propellant wrapped in a cloth and provided with US Army Special Nonelectric Cap, described in Ref 14, a 12 length of fuse and a lighter attached at the base of the shell. The remaining space in the shell was filled and lightly tamped with earth containing no gravel or stones. The shell was then placed at an angle of ca 30° in the desired direction and the fuse lighters on both the shell and the cord were pulled out. The shell acting as a rocket was propelled to a distance of ca 200ft while dragging the detonating cord with it. After several seconds the detonating cable exploded. For a m ore detailed description of this device, see Ref 1, pars 46.04-a to 46.04-i Demolition Hoses, used by some European countries, such as Germany and Czechoslovakia, were long flexible hoses made of various materials. One end of such hose was stationary while the other end could be projected to a desired distance across a mine field or other obstacle by means of a rocket, mortar projector or other device. Then a liquid ex pi, such as Myrol, which was used by the Germans(Refs 8 & 10), was pumped into the hose and the explosive detonated by means of a conventional initiating device placed at the stationary end of the hose. The Czechs used a device called Hadice which i s briefly described in conf Ref 7 Demolition Snakes, intended principally to breach minefields, may also be used to breach bands of log posts, steel rails, antitank ditches and some small concrete obstacles. A demolition snake consists of sections made up of two parallel linear charges of expls encased betw corrugated metal plates, bolted together to form an assembly rigid enough to be towed or pushed by a, light or medium tank yet flexible enough to pass over uneven ground. Detonation of snakes was accomplished from within a m oving or stationary tank by the impact of a .30 cal bullet from a machine gun against a vertical plate forming part of the two impact fuzes, one attached toward the leading end and one at the rear of the charged segments of the snake assembly

The demolition snake M2, described in Ref 1, pars 46.02 to 46.03 and in Ref 5,pp 288-9, is the earliest model. It was made of corrugated steel plates. The usual length of this snake was 400ft. The chge consisted of 10 lbs of 80/20 amatol per ft. The first 20ft of the snake and rear 60ft contained no expl. This prevented premature explns while pushing or towing. Gross wt of a 400-ft snake was ca 7 tons. Snake M2A1 was similar to M2 except that its load was 14 lbs of amatol per ft. Gross wt of a 400-ft snake was ca 8.5 tons. Snake M3 is the current model. It is described in unclassified Ref 5,p 289. The snake is 14" wide, 5" high and 400 ft 1 ong when assembled. Corrugated aluminum plates, 9ft long, fastened with steel bolts, washers and nws, form the body of the snake. A pear-shaped aluminum nose, attached to the forward end of the snake in such a way that the nose can sw ivel slightly, aids in guiding the snake over and around obstructions. Other components and accessories adapt the snake for pulling or pushing by a tank. One hundred twenty-eight demolition charges M2 are used with each M3 snake, 400ft long. Each charge M2 is elliptical in shape and weighs 401bs including ca 351bs of expl, which is 80/20 amatol with a booster chge of crystalline TNT at each end. The chges are loaded in 320ft of the 400-ft snake, giving an expl wt of 14 lbs per loaded foot. Dirt-filled tamping bags are placed adjacent to the charges and extending 10ft toward the nose of the snake and 20ft toward the rear to prevent the chges from shifting. Loading assemblies for bangalore torpedoes(see above) may be used as an alternative expl charge. Two fuzes, bullet impact, Ml are supplied with each demolition snake. Total wt of this snake is ca 9 tons including 4.5 tons of expls(Ref 5,p 289) Refs: l)Anon,WarDept Field Manual FM 531 (1944-5),pars 46.02 to 46.05-i la)Anon,'Ammunition Inspection Guide', TM 9*1904(1944), 270-1 2)Ohart( 1946),375-6 3)Anon,'Complete Round Charts*5981,ORDIM,9CO,Washington DC(1950), sheet 45 4)C.E.Ball, The Town Journal, April 1955,p66 5)Anon,'Ammunition General', TM 9« 1900(1956), 266-7 & 286-9 6)E.J.Murray & S.J. Lowell,PATR 2297(1956) (Conf) (Development of improved expl chges for Bangalore Torpedoes MlAl & M1A2 and Demolition Snake M3) 7)'Infor-mation Rept of the Central Intelligence Agency', No CS-LT-K-RC-3831,4 Dec 1956(conf) 8)PATR 2510(PB No l61270)(1958),p Ger 115 9)US Specification MIL-T-1339(Ord), Bangalore Torpedo MlAl 10)Dr Hans Walter,PicArsn,Dover,NJ; private communication ll)A.B.Schilling,PicArsn; private communication 12)'Ammunition Complete Round Charts',Book III, Ordnance Ammunition Command,Joliet,111, 15 Oct 1959, Chart 22 13)US Specification MIL-T-2087 14)US Specification MIL-C-14003A,Cap,Blasting,Special,Nonelectric (Type 1) and Cap,Blasting,Special,Electric(Type 2) (formerly known as Cprps of Engineers Caps) (See also this volume under BLASTING CAPS)

BAR. Browning Automatic Rifle. See under Browning's Weapons

Baratol is an expl compn contg Ba nitrate & TNT in various proportions, developed by the British and used during WWII. It was claimed that Ba nitrate acts not onl y as a non-hygroscopic and non-corrosive oxidizer and extender for TNT but also as a substance which improves the propagation of the detonation wave of TNT, Baratols are not as efficient expls as amatols(on a wt basis), but on a vol basis there is practically no difference

Originally there were the following two formulations for Baratols:

a) 80/20 Cold Mixed Baratol (Brit nomenclature), called 20/80 Baratol by the US nomenclature. It contains 20±2.0% Ba nitrate [freshly ground to pass the BSI(qv) sieve No 60 and dried to a moist content not higher than 0.1%] and 80±2.0% TNT (ground to pass the std BSI sieve No 25). This Baratol has been prepd by blending of ingredients at RT, preferably at the site of the plant where filling of ammo with Baratol takes place. Loading of ammo can be done either by hand stemming or by direct pressing. The prepd Baratol shall all pass No 8 BSI sieve and at least 75% to pass No 25 BSI sieve. Moisture content must not exceed 0.10%. No grit, visible impurities or foreign matter must be present b)90/10 Poured Baratol,(Brit nomenclature), called 10/20 Baratol by US nomenclature. It contains 10±1.0% Ba nitrate(ground to pass the BSI sieve No 72) and 90±1.0% TNT(Grade 1 or 2). Its prepn is as follows:

A freshly ground Ba nitrate is gradually added while stirring to molten TNT, preheated to 90°, not allowing the temp to drop below 85° during mixing. The mixt is cooled while stirring to the consistency of 'porridge' and poured into suitable molds to be solidified in slabs of ca 1/2" thickness. The slabs are broken into pieces suitable in size for biscuit(pellet) loading of ammo. The d of the slabs should be about 1.63 to 1.68. Any pieces showing sponginess are discarded. Another method of loading consists of pouring the 'porridge' into components in one or more increments. Before a 2nd or subsequent pouring is made, the shrinkage cavity from the previous pouring is broken through. Final toppings may be made by pouring the Baratol melt mix directly at 85° without allowing it to cool further in the melt pot. The props of 90/10 Baratol (British) were reported in Ref 2 as follows: co/or-buff; density of loading ca 1.65; mp 80-5°; brisance (by sand test)-36g sand crushed, vs 43 g for TNT; (relative brisance 84% TNT); detonation velocity - 5900 m/sec at d 1.65, vs 6900 for TNT;

corrosz'feness-non-corrosive; hygroscopicity-aonr hygroscopic; impact sensitivity-V2 vs 14 for TNT

on PicArsn App with 2-kg wt; power(by Trauzl Test>98%TNT,(by Ballistic Mortar>98% TNT; rifle bullet sensitivity-20% detonations from .30 cal bullet shot from a distance of 90ft; stability (therm al)-as stable as TNT; ases-as bursting chge in depth bombs, A/T(antitank) mines and some grenades

As both the above Brit Baratols have highly negative oxygen balance to C02 (-53.1% for 80/ 20 and -65.5% for 90/10 Baratol) (the method for calculating OB of a mixt is described under Bar-onal) two new formulations contg much higher percentages of oxidizer(Ba nitrate) were developed in the US. One contained: Ba nitrate 73 & TNT 27%(OB to C02 + 2.1% and to CO + 15.6%), while the other consisted of Ba nitrate 67 & TNT 33% (OB to C02 is -4.2% and to CO + 12.1%). The latter compn, called 67/33 Baratol in US and 33/67 Baratol in Gt Britain, is still in use and its props are as follows: booster sensitivity lOOg Tetryl detonates cast Baratol in 50% of trials through 0.32 of wax; brisance(by sand test)-26.8g sand crushed vs 48.Og for TNT(relative brisance 56% TNT); density (cast) 2.55; ex~ plosion temperature- ignites at 385° in 5 sees; Hygroscopicity- nil at 30° & 90%RH; impact sen-sitivity 35cm vs 90-100cm for TNT(BurMines App, 2kg wt); ll"(sample wt 24mg) vs 14" for TNT (PicArsnApp, 2kg wt); power — not given in refs listed below; sensitivity to initiation — 0.40g of Baratol require a detonator contg 0.20g LA & 0.10g Tetryl(Ref 5)

Preparation of 67/33 Baratol. The approx wt of Ba nitrate, preheated to ca 90°, is Added to molten TNT contained in a melting kettle equipped with an agitator. Mixing is continued until a uniform mass is obtained. Then the melt is cooled slightly while the agitation is continued and is loaded into ammo at the lowest temp at which it will flow freely(Ref 4)

Analytical Procedure Used at Picatinny Arsenal for Baratol( as described in CLR 121813). Transfer an accurately weighed sample of ca 2g dry Baratol to a 400ml beaker. Add 200ml of dry benzene and allow the mixt to digest on a water-bath for lhr. Transfer quantitatively the insol portion to a large tared sintered glass crucible (which has been previously washed with benz and dried at 100±2° for lhr) and wash its contents with four 25ml portions of benz, aspirating each time until most of the benz is removed. Dry the crucible at 100+2° for lhr, cool in a desiccator and weigh. The wt of residue is Ba nitrate Analytical Procedures Used by the British in clude detn of moisture content(max allowable 0.25%) and detn of composition. For the moist content, a 5g sample of pulverized material in a shallow dish is kept in vacuo over concd sulfuric acid for 18 hrs and then reweighed. The moisture free material is transferred to a Gooch crucible in which it is extracted with hot, dry benz until free of TNT. The crucible with residue is dried at 100° for 1 hr, cooled in a desiccator and re-weighed(Ref 3)

2)A1 l&EnExpls( 1946),89-90 and table,p 57

3)US Military Intelligence Division Reports R-979-51 & R-1149-51(1951) 4)PATR 1740,Rev 1 (1958)

Barborit. A Ger chlorate expl formerly manufd by the Sprengstoff-Fabriken Kriewald bei Gleinitz: K chlorate 90-92 & high boiling petroleum fraction 10-8%. Flash point of petroleum was required to be not below 105° and boiling point not below 242° /?e/:A.Marshall,'Dictionary of Explosives', Churchill, London( 1920), 12-13

Barbe(no first name or initial given) proposed-in 1883 to diminish the sensitivity of NC by incorporating organic or inorganic nitrates, preferrably AN. The same inventor proposed in 1885 to diminish the hygroscopicity of AN and to assure its neutrality by incorporating some Amm carbonate Refi Daniel(1902),56

Barbette. A mound of earth or a specially protected platform on which guns are mounted to fire over a parapet; a cylinder of armor on a warship that gives protection to the rotating part of the turret below the gunhouse; a fixed superstructure on an armored vehicle, usually with gun mount o£ limited traverse

Refs: l)F.W.F.Gleason, ArOrd 31, 369(1947) 2)Merriam-Webster's (1961) 175

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  • Monika
    How to make a bangalore torpedo from primacord?
    1 year ago

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