9mm Holecek
9mm RZK Rocket Rifle Cartridge
Article RKZ     (memories designer).

Ing. Ludek Podesva :

Rocket rifle RKZ

In sixtieth years were in the United States making advances with usage rocket principle for hand small arms.  
Furthest in this way get firm  MBA from California, which manufacture revolver (and later as well carbine) under
the name Gyrojet, shooting small rackets. Weapon work so, that at pressing trigger disengage hammer, which
strike on forehead cartridges - rackets placed in barrel, and strike by missiles with gout classical matches on
unyielding striker.  Combustion fumes from powdery load ( some powdery granule) fading over declination jet in
gout induction reactionary by force missiles in motion, the on its way puff out percussion striker thereby get
weapon to the next shot.
As well in   firm "Zbrojovka Brno" (armory works Brno) has been decision this evolutionary way don't miss out
and has been initiation with personal research, whose results was prototype rocket hunting rifle with working
title RZK ( Raketová Kulovnice Zbrojovka -  rocket rifle armory). At those work has been as well necessity
develop ( and for shooting trial also produce) personal rocket bullet.  Caliber cartridge has been 13 mm, his
longitude 60 mm and weight before shot 22 g. Cartridges was creation thin-walled steel shell ( wall thickness
0,5 mm) and jet gout, which be over lloaded linked with bullet jacket expanding  (beadung) and behind-border.
Jet bottom have after perimeter jet, which were declination  appearance lengthwise axis. Jet were from the
inside overlap aluminous folio, which partly provisory stuffing cartridges against penetration dampness, partly
provisory achievement correct initial ignition pressure ( after whose achievement folio rupture ) in rocket
motorcycle, whose working pressure was 80 atmospheres. Fading combustible fumes owing to these sloping jet
impart bullet before by leaving barrel sufficient number speed rotation, which provisory her steadiness en route
bullet.  Over relatively short burning time powdery load (  circa tenths second) no-combustible all load in barrel,
but perhaps as far as 13 m from muzzle, where bullett achieve maximum speed 450 m/s. Among jet gout and
powdery propellent filling be situated fire grate preclusive movement powdery grains at burning and possibilities
impaction jet.
Like impulsive filling has been using one powdery grain ( extract from rocket paste)  with jacketed exterior ( this
is adjustment prevent seasoning grains  on exterior.). Inside moulded inner grain shape ( handling needed
course sizes burning surface thereby also size traction) be placed igniter longitude 30 mm totalled cotton woven
line nitrate on 12,05 % N ( it is virtually clean nitro-cellulose). That manner was using for easy dosage and
arrange at loaded. Because from all infancy was  emphasis at it, to wasn't erosion no one foreign patent, has
been in contradistinction to mechanical ignition Gyrojetu using ignition electric. In middle part jet gout has been
set specielni electric primed, whose one pole be attached to frame cartridge and second pole was  you-led on
insulated pin in the centre jet bottom. On that touch-down sliding spring-loaded contact placed in bodies arms.
Weapon has been solving like what perhaps lightest (maximum total weight without cartridges-1,8kg) and
simplest (in the picture show through really minimum number parts, from that in principle no mobile, or
extremely exacting on accuracy). Gunstock arms has been making (in terms of simultaneously wo-circulatory
research possible compensation for hickory wood) from wood poplar, specially impregnated in high pressure
autoclave for obtaining needed mechanical feature. His lower specific weight as well notably contributing to
general low weight arms. Barrel armst has been making thin-walled steel tube with drilled cross hole in rear
parts, which removal combustible fumes over steel canopy barrel way  from shooter. Barrel procuration sighting
arrangement has been by the help of strike peg gripping by two nut to bed arms. Bed arms and side cover were
fabrication from aluminous alloy self-flinched anodized with resulting colorings to black. Steel parts  - barrel
(inside chromium-plate), canopy barrel, single parts magaziner, safety and  small change fitting were surface
modified alkaline oxidation. In shaft bed arms was removable lodgment magazine for five rocket cartridges,
which were firing right from the magazine.  Cartridges be in magazine kept against undesirable axial movement
stirrup, whose conducting parts lock-on to the behind-hemming groove in bullet. After shot and closure residual
pressure gas was to the launching position transmission next bullet, whereas contact electrical  primer touch-
down, on spring-loaded sliding contact gripping pendulous in bodies arms. That was connection with micro
changeover switch , which in quiescent position close charging circle condenser and battery placed in gunstock
arms. In bodies arms below side cover has been coeval with condenser and micro changeover switch place
simple shambles with two-ply flat spring, whose one end was leant about projection in bodies arms and served
as cushioning trigger, second end handled at pressing button  micro changeover switch. Hereat be out of the
question risk of damage mechanism micro changeover switch excessive stress on the trigger and on his button.
At pressing trigger micro changeover switch interrupted charging circle  and stapled well-lined condenser to the
launching circle with cartridge.
Caliber condenser has been fixed term so, to his electric charge with reserves sufficed on of shoot electrical
primer in bottom bullet and to in essence discharge on zero so, so as to couldn't  (at no-vacation pressure on
the trigger after shot) fire next rocket bullet forwarded in magazine to the firing position. After vacation trigger
micro changeover switch again stapled charging circle, which was in ultrashort time (  tenths second) capable
again load condenser  for shoot next cartridge. At stapled charging circle after full recharge condenser already
next electric current already practricaly non - cirkulate, so that insertion battery have had without firing service
life same like has been their warehousing durability. Capacity of the number of likely shot move  in thousands ,
so that has been practicaly inexhaustible and has been restricted only lifetime battery. Trigger has been
mechanically blocking corn-wise traverser safety placing at the rear of lucik.  For transportation has been likely
weapon easily lay out for two lots after permission two screws (with notch  for coin) in gunstock latching into peg
barrel gripping to bodies arms nuts.
Effected background research has been inquest, that this way proposition weapon is patent clean and
undisturbed any foreign law. On the contrary - new constructional element arms were patenting and for these
gimmickry has been grant author's certificate.
On beginning the eightieth years was next development those arms closed out, because weapon his
conception fully unsetting to the at that time newly promote conception production Zbrojovka  Brno.

Ing. Luděk Podešva.
Van Hee and Czech Rockets from Woodin Laboratory Collection.
Czech Rocket Data