From: Won-Soon Lau <engp1186@nusunix1.nus.sg>
Subject: Re: 106mm Recoiless Rifle - Rocket or Gun?
Organization: National University of Singapore
Date: Thu, 12 Nov 1992 17:36:09 GMT


From Won-Soon Lau <engp1186@nusunix1.nus.sg>

>From ppugliese@pimacc.pima.edu
: 
: My brother was a recoiless rifle gunner when he was in the US army. The RR
: had several interesting features. One was the "kill zone" behind the gun.
: Apparently the exhaust was so intense that there had to be a clear area
: behind the gun (you ever see a picture of one firing? BIG cloud of dust!)

    This is known as the back-blast area.  It is a equilateral triangle and
    each side is 23m.  One would surely get killed if standing less than that
    away from the breech-block.  For train-fire, we put that figure to 50m.
    The back-blast requirement is the main constraint in deployment of the gun.

    The effective range of the gun against stationary target is about 1100 m
    although you can fire up to 7.7 km theoretically.  Ranging is done
    by a 0.5 inch coaxial gun mounted in parallel to the main barrel.
    There are upgrades where the ranging gun is replaced by a laser range-
    finder but not sure about any night-capability without illumination.

    There are two types of round: HEAT and HESP.  Both can be used against
    armours although the HESP can be used for bulkers and concrete buildings.
    Each round weighs 17 kg and is about 1m in length.  The warhead is only
    about 5 kg so you can imagine the deafening burst when firing. Muzzel
    speed for the 106mm round is 504 m/s.

: & one of the functions of the asst gunner was to sit facing backwards with
: a safety switch in his hand. If the area wasn't clear then he wouldn't

    I don't remember a safety switch with the gun.  The job of the asst
    gunner (aka loader) is to load/unload the round.  The round is only
    loaded to the safe position (on the breech-block handle).  Then, he is
    to ensure that the back-blast area is clear of any personnel.  The
    gunner is the one who has to put the gun into firing mode and do the
    aiming/firing.

: allow the gun to fire. Another feature was that the instant dust cloud
: the thing raised blinded the crew many times but , presumably, would at-
: tract alot of tank or AFV anti-personnel fire. RR duty assignments was
: NOT something that was sought after. 

    Indeed the dust or flash (at night) can be seen miles away.  The
    skill is in deployment of the gun under good cover and concealment
    and after firing, an unexpose route for withdrawal.  Also, by
    interleaving the fires from several guns (average about 1 round in 3 sec)
    one can achieve an overwhelming effect before the enemy can react.

    Since the gun is heavy (220 lbs), normally it has to be operated on
    jeep.  Contrary to what you think, RR assignment is one of the most sought
    after assignment because of the "luxury" of the vehicle instead
    of on foot in the infrantry units.  (The only one is the mortar unit.)

: 
: PHIL
: p.s. I *did* think the jeep with 4 106mm RR's on it looked neat though!
: What was it called? 'Ontos', maybe? Anyway, has anyone any experiences
: with those they'd care to relate?
:  
    Can you have 4 106s on a jeep?  The the quarter ton jeep may not be able
    to carry so much load.  I have seem M113 mounted with 2 106s but not 4.

    I hope that the information are correct as that part of my memory was
    last refreshed 6 years ago.  Now I use guided-weapon. :-)


Won-Soon Lau

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