close

Вход

Забыли?

вход по аккаунту

?

Патент USA US3060864

код для вставки
Oct. 30, 1962
J. s; DUNN
3,060,856
PRACTICE ROUND OF AMMUNITION
Filed March 2, 1959
50
E
Í
12a 10a
m
i
é
BY â
`
‘0"
ATTORNEY
icc
3,968,355
“Fatented Get. 30, 1962
2
18, 1894, to W. M. Thomas) used a shorter lead bullet
3,060,856
and compensated for such shorter lead bullet by providing
PRACTICE RGUND 0F AMMUNITIÜN
asheet metal extension on the neck of the cartridge case.
This type of practice was subject to all of the above-men
tioned disabilities of alive round of ammunition, includ
ing high cost and lack of reusability.
Filed Mar. 2, 1959, Ser. No. ’796,483
Later, as shown in U.S. Patent No. 1,823,022, issued
9 Claims. (Cl. 1in-_41)
September l5, 1931, to F. Blechta, a hollow lead-core
projectile having a transverse partition to protect the lead
The present invention relates to ammunition and, more
particularly, to a low-cost practice round of ammunition 10 from the ilash and coated externally with copper was
used to provide better trajectory stability and to prevent
which is reusable without the use of complicated tooling
lead contamination of riiie bores. Manufacture of such
or expensive recovery operations.
a complicated projectile today would add to, not decrease,
In the training of police and defense personnel to de
practice round expenses. In addition, the pojectile was
velop an adequate skill and proficiency in the ñring of
not, of course, capable of being used again.
the weapons employed thereby and in the maintenance of
.Ioseph S. Dunn, Clark ri‘ownship, Union County, NJ.,
assignor to Plastic Training Products Company, Bloom
field, NJ., a corporation of New `lersey
such acquired proficiency initial and continued practice
is essential. Heretofore the use of live ammunition for
such instructional and practice sessions has been the only
satisfactory answer to the problem. This use of live
ammunition is necessary because heretofore practice
rounds of ammunition were either inaccurate or provided
no cost saving to the municipal, State or Federal agency
using them. Due to the rising spiral or inflation this cost
of live ammunition used for instruction and practice pur
For cheapness of manufacture and short range use a
hollow gilding-metal projectile of the type shown in U.S.
Patent No. 1,892,158, issued December 27, 1932, to l.
Matthews was suggested. A flared open mouth on the
forward end of the bullet retarded the flight of the bullet
and an enlarged rear portion thereon formed a rifle-barrel
bearing. Under present day conditions lack of reuse, high
cost and lack of accuracy have reduced such type of prac
tice round to obscurity.
The practice cartridge shown in U.S. Patent No. 1,902,
poses for such municipal, state and federal agencies has 25
771, .issued lMarch 21, 1933, to A. F. Gardos comprised
become an increased burden to the taxpayer. As ex
a blank cartridge inserted in the tip of the cartridge case
amples, the .45 caliber automatic, .38 caliber Special and
for use as the propelling charge, the blank cartridge being
.30 caliber Springfield ’O6 live rounds of ammunition cost
tired by an auxiliary firing pin contained in the base of
12í¢, 9¢ and 21¢ each respectively.
In an attempt to reduce such instruction and practice 30 such cartridge case. The complex number of machined
parts employed in this practice round of ammunition re
costs, the cartridge cases of the fired live rounds of arn
sulted in high costs, thus outweighting the desirable fea
munition are recovered, the primer being punched from
ture of ease of reloading.
the cartridge case by a special tool, and such cartridge
Finally a practice round of ammunition of the type
case being recovered by machine operations to adapt
such cartridge case for reuse. These machine operations 35 shown in U.S. Patent No. 2,812,713, issued November
l2, 1957, to A. L, Fitzsimmons was introduced. The
comprise reaming the primer recess in the cartridge case
to adapt such recess to receive a new primer and reneck
ing or reducing the projectile aperture to receive a new
hollow cartridge case was shaped to simulate a conven
tional case and projectile and was adapted to contain a
pellet. A detachable head housed a percussion cap and
projectile. This recovery procedure is expensive from the
standpoint of the tools, machines and hand labor in 40 a solid cylindrical firing pin for exploding the cap charge
through suitable ports extending to the pellet. 'This
volved. In addition, the lead projectile of the live round
practice round cost about $1.50/round, Was reusable upon
ammunition is not reusable. Further the recovered car
the addition of a new pellet and percussion cap but
tridge case must be supplied with a new primer, powder
lacked the accuracy of the corresponding live round of
and projectile before it is operable for use in a Weapon,
thereby `further adding to the cost. The net result of the 45 ammunition.
It is the general object of the present invention to avoid
above-described recovery techniques, as applied to live
and overcome the foregoing and other diíiiculties of and
rounds of ammunition, has resulted in no appreciable
saving.
objections to prior-art practice rounds of ammunition by
In the past many futile attempts have been made to 50 the provision of an improved practice round of am
munition which is formulated from readily moldable matc
achieve a practice round of ammunition, which is adapted
rials and is low in cost.
for use in conventional iirearms, provides equivalent ac
Another object of the present invention is the provision
curacy to a live round of ammunition, duplicates normal
of an improved practice round of ammunition, the es
ñring conditions, is low in cost and is reusable.
sential components of which are reusable for about fifty
The earliest practice cartridge (of the type shown in
U.S. Patent No. 517,719-, issued April 3, 1894, to G. D. R.
Aikin) utilized a conventional projectile and modified the
cartridge case by employing a shallow charge chamber dis
posed behind such projectile and communicating with
55 shots without requiring extensive recovery operations or
the use of special tools thereon.
Still another object of the present invention is the
provision of an improved practice round of ammunition,
the spent primer of which is readily removable by hand
the primer recess by means of a small bore. Such prac 60
pressure on a simple hand tool, such as an awl or ice
tice rounds are not reusable and have long since been
pick.
eliminated from use. To render such practice round re~
Yet another object of the present invention is the pro
usable the cartridge case was later provided with a
vision
of an improved practice round of ammunition which
cavity adjacent the primer recess and adapted to house a
primer-catching device of the type shown in U.S. Patent 65 may be reassembled by hand and a new primer added
thereto with the aid of the back end of a simple hand
No. 539,327, issued May 14, 1895, to G. D. R. Aikin.
tool.
The resilient catches on the primer-catching device com
A further object of the present invention is the provision
plicated its structure and became readily work hardened
of an improved practice round of ammunition which pro
thereby defeating its purpose. In today’s market its cost
vides the equivalent accuracy of a similar live round of
would be prohibitive.
70 ammunition during its entire iiring life.
Another earlier prototype of a practice cartridge (such
as shown in U.S. Patent No. 531,233, issued December
A still further object of the present invention is the
provision of an improved practice round of ammunition
The moldable material of the cartridge cases 12 must
be able to withstand the heat generated by the flash or
propelling charge even under ambient outdoor tempera
tional íirearm and provides a close duplication of normal
-iiring’conditions so that such user is not affected by the
tures of about 100° F. Heat distortion temperature (° F.)
at a liber stress of 264 p.s.i. lis the temperature required
transition to the use of live rounds of ammunition with
to permit an arbitrary standard amount of deflection by
such conventional firearm.
a standard load, under gradually increasing temperature
Another object of the present invention is the provision
of improved practice rounds of ammunition for firearms
and measures this heat-resistant property. In addition,
such cartridge case 12 must be hard enough to withstand
of various calibers, which rounds utilize a universal primer
thereby reducing the number of stock parts required for 10 many chamberings in the ñrearm. 'I'his hardness property
is measurable by the Rockwell test which expresses resist
the various calibers and further simplifying the reloading
' operation.
ance to penetration by brief contact with a 1/2” spherical
ball subjected -to a 10 kg. minor load and a 60 kg. major
Another object of the present invention is the provision
of an improved practice round of ammunition having a
load. Further, a rim 19 of the cartridge case 12 must
cartridge case provided with a novel primer recess which 15 withstand the force of the firing pin striking the primer
30, which force would tend »to shear off the rim 19 and the
facilitates the loading and unloading of the primer.
shock or impact of numerous extractor contacts which
Still another object of the present invention is the pro
might dent or chip such rim 19. This impact strength is
vision of an improved practice round of ammunition
having a cartridge case provided with a novel guide
measured by the Izod test in ft.-1b. per inch of notch and
aperture which facilitates the flow of the propelling 20 represents the energy required to break a notched test
bar by means of a sharp blow, thus indicating the shock
, charge t'o the ñash chamber with a minimized resistance
resistance of the moldable material.
to and loss of propelling force.
The following table illustrates -the operating ranges of
` The aforesaid objects of the present invention and other
the cartridge case 12;
objects which will become apparent as the description
proceeds are achieved by providing a practice round of 25
which enables the user to practice in the use of a conven
Properties:
. ammunition having a hollow moldable cartridge case pro
vided with a flash chamber and a primer-receiving aper
ture in one end of such ñash chamber, a moldable pro
Heat distortion temperature, ° F ...... __
Hardness (Rockwell) ________________ __
jectile of relatively diiferent hardness than the cartridge
Impact strength ft.-lb./inch of notch (1/2 X
case and having a shank portion of reduced diameter 30
which is insertable by hand into the other end of the
Range
>115°
30-118
1/2 in. notched bar., Izod test) ______ __ 1.0--12.0
As an example, and not by way of limitation, such
cartridge case12 may be made of a vinyl butarate plastic
such as Butacite, the trade name of the product made by
- simple tool into the primer-receiving aperture in substan
- tially hermetic engagement therewith and operable as the 35 Du Pont de Nemours & Co., of Delaware, a polyethylene
molding compound such as Alathon, the trade name of
propellant for tiring the projectile from the cartridge case,
' flash chamber in substantially hermetic engagement there
with and a primer insertable by the hand operation of a
the product made by the Du Pont de Nemours & Co., of
the spent primer being manually removable from the
Delaware, or a nylon molding compound, such as Fiber
' cartridge case by insertion of the hand tool into the pro
iil, the trade name of the product made by the Fiberlil
Corp., of Indiana.
jectile-receiving end of the ñash chamber to dislodge the
Y used primer therefrom.
' reference should be had to the accompanying drawings,
While I am aware of the prior use of plastics, such as
formaldehyde condensate, for a cartridge case as dis
wherein like numerals of reference indicate similar parts
throughout the several views and wherein:
to P. E. Pihl et al.; cellulose acetate for a cartridge case
For a better understanding of the present invention
closed in U.S. Patent >No. 2,083,665 issued June l5, 1937,
FIG. 1 is a perspective view of a .45 caliber practice 45 as taught in U.S. Patent No. 2,137,350, issued November
22, 1938 to H. A. Roberts; and polyethylene as taught by
round of ammunition of the present invention.
U.S. Patent No. 2,862,446, issued December 2, 1958, to
FIG. 2 is an enlarged exploded side-elevational view of
L. Ringdal, such uses were confined to live rounds of
the .45 caliber practice round shown in FIG. 1.
ammunition and were not employed in practice rounds of
FIG. 3 is a fragmentary enlarged view of the lefthand
portion of FIG. 2 and showing the details of the primer 50 ammunition to provide the structure and beneficial results
of the present invention.
recess and guide portion.
The cartridge case -12 is provided with a flash chamber
FIG. 4 is a perspective view of a .38 caliber Special
14, the right-hand end of which, as viewed in FIG. 2,
~ practice round of ammunition of the present invention.
serves yas a projectile-receiving aperture 16. The left
FIG. 5 is a view similar to FIG. 2 but showing the
hand
end of the cartridge case 12 is provided with a
55
.38 caliber Special practice round of FIG. 3.
primer-recess 18 which extends inwardly from a feather
FIG. 6 is a perspective view of a .30 caliber Springfield
edge rim 21 and terminates in a conical inwardly-tapering
’06 practice round of ammunition of the present inven
guide portion 20 leading -to a venturi aperture 22 which
tion.
communicates with the left-hand end of the ilash cham
FIG. 7 is a View similar to FIGS. 2 and 4 but of the
ber 14 by means of an outwardly-extending conical guide
.30 caliber Springfield ’06 practice round shown in FIG. 5. 6,0 portion
24».
Although the principles of the present invention are
'I'his feather-edge rim 21 ('FIG. 3) desirably about
broadly applicable to any caliber of conventional ammuni
.001” in thickness provides an entrance-lip diameter which
tion, the present invention is particularly adapted for use
is .0Q2-.003” less in diameter than the diameter of a
in conjunction with the .45 caliber automatic, .38 caliber
Specialand .30 caliber Springfield ’06 type rounds of am` 65 primer 30, namely .210”. The guide portion 20 (FIG. 3)
is disposed at ‘an angle (ß<45°) with the longitudinal
munition and hence it has been so illustrated and will be
axis of the cartridge case 12 and is essential for rapidly
so described.
directing the propelling charge to the venturi portion 22
With speciiic reference to the form of the present inven
-tion illustrated in the drawings, and referring particularly
to FIGS. 1 `and 2, a .45 caliber practice round of the am
munition of the present invention is indicated generally by
the reference numeral 10.
This practice round of ammunition 10 has a cartridge
case 12 formed of a moldable plastic having properties
necessary to perform certain essential functions.
thereby preventing continement of such propelling charge
70 or the creation of a rearward thrust on the iired primer
30, which thrust might dislodge the latter.
It will be understood that in orderVto adapt -the car
tridge case 12 for use with a conventional .45 caliber lire
75
arm, the length (.890"’), rim diameter (.475”) and diam
eter of the body (.470”) of the cartridge case 12 are iden
3,060,856
5
ñash chamber 14, as viewed in FIGS. 1 `and 2, to receive a
Patent No. 355,653, issued January 4, 1887, to A. T. Loyd;
the rtoy rubber projectile of U.S. Patent No. 2,539,968,
issued January 30, 1951, to T. H. Payne; and the frag
menting projectile for live ammunition and formed of
shank portion 26 of a projectile 28 in substantially her
metal filler with a binder of ethyl cellulose disclosed in
tical to the similar dimensions of the .45 caliber live round
of ammunition.
Y
For the purpose of adapting the right-hand end of the
metic engagement and thus prevent leakage of the ñash
or propelling charge there-between, such shank portion
26 has a diameter of `about .300” and the diameter of the
ñash chamber 14 is desirably .002”-.003" smaller. The
projectile 28 has a relative diñïerence in hardness from
the cartridge case 12. By way of example, and not as la
limitation, -the projectile 28 being molded from a softer
moldable material than the above described moldable
material used in the cartridge case 12, such shank por
tion 26 is insertable by hand into the right-hand end of
the ñash chamber 14 in the less resilient cartridge case
(without the use of tools) to accomplish the substantially
hermetic joint. This insertion operation is similar in prin
ciple to the inserting of a resilient cork in the aperture
of a glass bottle.
20
So that the primer 30, suitably -a Remington Large pis
US. Patent No. 2,593,637, issued April 22, 1952, to L. C.
Weldin. None of these projectiles are for use in a prac
tice round of ammunition to provide the structure or re
sults contemplated by the present invention.
When the firing pin of a conventional .45 caliber lire
arm (not shown) strikes the primer 30, such primer 30
explodes and the resultant íiash or propelling charge is
guided by the tapered guide portion 20 to the venturi
portion 22 (having a diameter of about .099”) where the
velocity of such propelling charge is increased, thus per
mitting such propelling charge to erupt (by means of the
tapered guide portion 2.4) into the flash chamber 14 with
attendant firing of `the projectile 28 from the barrel of
the firearm (not shown) toward the practice target (not
shown).
Assuming the shank portion 26 of the projectile has a
tol primer No. 21/2 primer (having an outside diameter of
length o-f about .187” projecting into the flash chamber,
about .210” and a length of about .l19”) may be seated
the length of the ñash chamber 15 is about .750" and
in the primer recess 18, such primer recess has a length of
resultant volume
about .120" for seating the primer l30 inside the feather 25
edge rim 21 at the entrance to the primer recess 18. Such
('îggy '750:.538 cu. in.
primer 30 is started through the rim 21 in the primer re
cess 18 by hand and pushed into such primer recess by the
This volume V.45 for convenience of manufacture and
ilat top of the wooden handle of an awl or ice pick (not
simplicity of use, is held constant (for use with the No.
shown) held in the hand of the loader. The rim 21 in 30 21/2 primer 30) in the .38 caliber Special practice round
cartridge case 12 (which is more resilient than the primer
of ammunition 10a shown in FIGS. 4 and 5 and the .30
30) permits the primer 30 to `snap fit into the primer recess
caliber Springfield '-06 practice round of ammunition 10b
18 and causes the inner end of the primer 30 to seat
shown in FIGS. 6 and 7.
against the tapered guide portion 20, thus locking the
In order to render the projectile 28 (having a weight
primer in place and forming a substantially hermetic seal 35 of about 20 grains as compared to 200 grains for lead
between the primer 30 and the primer recess 18. This
projectile used in live rounds of ammunition) ballistically
method of loading the primer is an improvement over the
operative in conjunction with the propelling charge de
method shown in U.S. Patent No. 2,381,083, issued Au
veloped by the primer 30, the diameter (.450”) of the
gust 5, 1945, to I. S. Shuñ‘lebottom, which patented method
body of the projectile 28- is the same as a conventional
comprises heating the cartridge case of a live round of 40 projectile but the length of such body is about .135” long
ammunition after insertion of the primer to secure the
er, thereby providing an overall length (l.400") in the
primer therein.
practice round of ammunition 10 of the present invention
The moldable plastic projectile 28 is formed of a mold
as compared With a length (1265") of the conventional
able material which is softer and more resilient than the
live round.
45
plastic employed in the cartridge case 12.
In order to reuse or recover the cartridge case 12 and
The projectile must ybe hard enough to withstand the
projectile 28 of `the iired practice round of ammunition
shock of tiring and the friction of movement through the
10, the projectile 28 is recovered from the target area.
barrel of the ñrearm, yet sufficiently soft to be grooved
The blunted end of the awl or ice pick (not shown) is in
by the lands in ‘the barrel, thus giving such projectile the
serted into projectile-receiving aperture 16 and through
proper spin which insures ystability and accuracy of the 50 the ilash chamber 14, the venturi portion 22 and into
projectile in iiight. In addition, such projectile must
contact with the ñred primer 30. Manual pressure on
have the necessary impact strength to withstand the im
the handle of the awl or ice pick is suñicient to dislodge
pact incurred upon striking hard objects, such as a target,
the spent primer 30 from the rim 21 of the primer re
without losing its original shape. Further, the tempera
cess 18. A new primer 30 is then seated in the primer
ture of the propelling charge from the primer 30 must not 55 recess 18 as hereinbefore described, the projectile 28 is
deform the shank portion 26 of the projectile 28 so as to
seated in the projectile-receiving aperture 16 by hand
disturb -the substantially hermetic seal between such shank
and the practice round of ammunition 10 of the present
portion 26 and the projectile-receiving aperture 1'6 in the
cartridge case 12.
invention is ready for retiring.
As hereinbefore mentioned a conventional live round
The properties of a suitable moldable material for the 60 of .45 caliber ammunition costs about l2¢/round. The
projectile 28 are shown in the following table:
cartridge case 12 and projectile 28 of the above-described
Properties:
Range
practice round of ammunition 10 cost about 3¢ and the
Heat distortion temperature,° F ____________ __ >105
primer 30 sells for .95¢, thus giving an initial cost per
round of about Mt of the corresponding conventional
Hardness (Rockwell) _____________________ -_ 25-110
65
Impact strength ft.-lb./inch of notch (1/2 x 1/2 in.
live round. In addition, the practice round of ammuni
notched bar., -Izod test) ________________ __ 1.0-5.2
tion 10 of the present invention is capable of being tired
over fifty times at a cost of .95¢/refiring with no loss of
As an example, and not by Way of` limitation, such ma
accuracy over the conventional live round at Sty-50'.
terial may be `a polyethylene plastic such as Alathon, the
Referring now to the .38 caliber Special practice round
trade name of the product of Du Pont de Nemours, of 70
of ammunition 10a (FIGS. 4 and 5) and -to the .30 caliber
Delaware, or a cellulose acetate molding materials, such
Springñeld ’06 practice round of ammunition 10b (FIGS.
as plastacele, the trade name of »the product of Du Pont
6 and 7) it will be noted that like numerals of reference
de Nemours, of Delaware.
’
with the suiiix "a” and “b” appended thereto respectively
I am, of course, aware of the live-round projectile
V'formed of lead, papier-mâché and pulp shown in U.S. 75 indicate parts similar to the above-described similarly
>3,060,856
numbered lparts in FIGS. 1, 2 and 3. To permit universal
While in accordance with the patent statutes one best
known embodiment of the present invention has been
illustrated and described in detail, it is to be particularly
understood that the invention is not limited thereto or
use of the No. 21/2 primer 30 in the practice rounds of
ammunition 10a and 10b and thus simplify procedures
and reduce costs, the primer recesses 18a and 18b are
identical to the primer recess 18. Tapered guide portions 5 thereby.
20a and 20b and 24a and 24b, as well as rims 21a and 2lb
I claim:
and venturi por-tions 22a and 22h have the same dimenl. A low-cost, reusable practice round of ammunition
sions as the corresponding parts of the practice round of
comprising a plastics tubular cartridge case having an
ammunition 10 shown in FIGS. l and 2. Since the pracend closure and an open end, said end closure being
tice rounds of ammunition 10a and 10b are of smaller 10 provided with a prirner-receiving aperture, a plastics
caliber, the ilash chambers 14a and 14b are longer but
projectile projecting from said open end of the cartridge
the volumes thereof V.38 and V3() are substantially equal
case, said cartridge case being provided with a venturi
to the volume V.45 (.538 cu. in.) of the flash chamber 14
portion between said primer-receiving aperture and said
of the practice round of ammunition 10 (FIGS. 1 and 2).
open end and spaced from said projectile, said projectile
The following table gives a dimensional comparison in 15 having a relatively lower hardness than said cartridge
inches between the practice rounds of ammunition 10a
case and being connected with said open end of the cart
and 10b of the present invention and the corresponding
ridge case, and a standard cartridge primer having an
conventional live rounds:
anvil in said primer-receiving aperture and operable as
Over-
Cart.
all
Case
Rim
Diam. Diam
Diam. Diam. Leu. of Len. ot
Diam. of Cart. oiNeck
Length Length ofCai-t. Case
Case
of
ofCart Body
Case
of
Shanlg
Body
Shanlr oiProJ. olProj.
oíProJ. ofProJ.
.38 cal. S eelal live round ____ _.
1.505
1.125
.430
.380 ______ ._
.38 Speel
practice round 10a-..
1.615
1.200
.430
.380 ...... -_
.355
.30 caLSprlngñeld’OGllveround.30 cal. Springfield ’06 practice
3.250
2.480
.465
.465
taper
.330
:305
303~
round 10b ................... -_
2.860
2.485
.465
. 465
.336
.305
.240
.187
.415
-225
.187
.375
The above-noted dimensional variations between the
practice rounds of ammunition 10a and 10b and the cor-
the sole propelling charge for ñring said projectile from
said cartridge case, said venturi portion being operable
responding conventional rounds are for the purpose of pror-
to rapidly increase the pressure behind said projectile
viding projectiles 28a and 28h having essentially the same 35 Upon actuation of said primer.
weight (namely 2() gl-ains) as the projectile 28, thereby
2. A low-cost, reusable practice round of ammunition
.adapting Suçh projectiles 23a and 2gb to respond unias set forth in claim l wherein said cartridge case has
formly to the same propelling charge from the universal
a Rockwell hardness in the range 0f abOut 30-118.
primer 30 and the substantially uniform volumes (VAS,
3. A low-cost reusable practice round of ammunition
vos and vso) of the sash chambers 14, 14a and 14h 40 as Set form in claim 1 wherein said projectile has a
respectively. 'I‘he cartridge case 12a of the .38 caliber
Rockwell hardness in the range Of about 25-110.
Special practice round of ammunition 10a, FIGS. 4 and 5,
4' A 10W-cost reusable Practice found 0f ammunition
is longer than the cartridge case of the corresponding live
as Set form in claim 1 Wllefelll said cartridge case has
round so that when the round 10a is loaded in the firea Rf’ckwell hardness in the fange 0f about 30-118 and
arm (not shown) such case 12b rests against the centeran unpact stfeugtll 1Z0@ units in the range 0f abOllt
ing slope of the cylinder chamber, thereby insuring the 45 1-0-12~0 and Sald Pfclcctlle has a ROCkWell hardness in
sealing of the propelling charge and prevents the rim 19a
the range .0f about 25-110 and au impact strength in
of the cartridge case 12a from being ruptured by the force
Izod umts 111 the fange 0f about .LO-52"
of the ñring pin striking the primer 30 and from forcing
5- A IOW'ÈOSÍ: reusable Practice found 0f ammunítiOn
such rim 19a from the cartridge case 10a, thereby preas seit fom? m Clau-“_ 1 wherein Said e‘ud closure iS 3.150
venting case 10a from the being extracted and rendering 50 PfoVlÉied Wlth a fesll'leut feather-edge Ilm at the entrance
case 10a unserviceable.
to said~prmier-receiving aperture, and said primer is
It will be recognized by those skilled in the art that
locked 1n substantially hermetic engagement with said
the objects of the present invention have been achieved
pnmer'reœlvmg aperture by Saud f1m~
by providing an improved practice round of ammuni_ 55
. _
6. A low-cost, .reusable practice round of ammunition
tion which is formulated from readily moldable materials
as seit forth nl dann 1 Whefejn Saïd Prolectlle has a Shank
and is low in cost. This improved practice round of
pm_uon of Shghtly large? dlameier “ian Saïd ope? end»
ammunition is reusable for as many as ñfty shots Without the necessity (after each ñring thereof) of extensive
which shank Porilon 1s dlsposed m sald. open end m sub'
stanuauy hermetic engagement .therewlth'
_,
recovery operations on its components or Without the
7‘
.low'cost’ r‘ajusable Practlœ r’ound of ammumtlon
use of special toom In addition, the spent prime1_ of 60 comprising a plastics tubular cartridge case having an
such improved practice rounds of ammunition is readily
removable from the cartridge case by the application
end .closurq and al? open c_nq’ Saïd end qlosure being
prqvlded~w1th .a pnmer'reœlvmg aperture. m. commi1m`
of hand pressure on the simple hand tool, such as an
çatlon W1th~sald Open end’ a plasilcs molecule prolect'
awl or ice Pick. The improved practice round of am- 6 má from iald op 6.11 end of lha carmdge. Czise’ arid a Siand‘
munition may be reassembled by hand and a new primer
5 ar -carmdge Immer havmg an anvll m sald prmier'
added thereto by pushing the primer into place with the
rîlcewmg apeiture .and operiìble as the? sole I_’TOPelllIlg
handle end of the awl or ice pick. This improved practice round of ammunition provides the equivalent ac-
c Érge for ñrmg said molecule om said cartndge (.:zise’
' .low'cost’ r‘iusable pracuce @und of ammlimtlon
curacy of the corresponding live round of ammunition, 70 êgälpâlâïlg a pâastlcs tubular cartlfldge case havmg .an
and close 'duplication
of normal tiring_ I conditions with
v
ccl‘fespcudlug llVe Icuuds 0f aluuluultlcu s0 that che
provided with a primer-receiving aperture in commum
îâïlásoïfloânîïîîieâoïl;
tlîâ tflijmsltlou from the Practice
‘
_ o e ive rounds of ammunition
from
said open end of the cartridge case, said projectile
having a relatively lower hardness than said cartridge
when using conventional firearms.
re~ an all open ein; said end closure bem?
cation with said open end, a plastics projectile projecting
75 case and being connected with said open end of the
3,060,856
cartridge case, and »a standard cartridge primer having
an anvil in said primer-receiving aperture and operable
as the sole propelling charge for ñring said projectile
from said cartridge case.
9. A low-cost, reusable practice round of ammunition
comprising a plastics tubular cartridge case having an
end closure and an open end, said end closure being
provided with a primer-receiving aperture, a plastics
projectile projecting from said open end of the cartridge
case, said cartridge case being provided with a venturi 10
portion between said primer-receiving aperture and said
open end and spaced from said projectile, and a stand
ard cartridge primer having an anvil in said primer
10
receiving aperture and operable as the sole propelling
charge for tiring said projectile from said cartridge case.
References Cited in the file of this patent
UNITED STATES PATENTS
1,853,262
Dickerman __________ __ Apr. 12, 1932
2,862,446
Ringdal ______________ __ Dec. 2. 1958
FOREIGN PATENTS
16,230
10,288
408,214
535,992
Great Britain ______________ __ of
Great Britain ______________ __ of
‘France ______________ __ Jan. 19,
France _______________ __ Feb. 4,
1884
1904
1910
1922
798,002
Great Britain ___________ __ July 9, 1958
Документ
Категория
Без категории
Просмотров
0
Размер файла
809 Кб
Теги
1/--страниц
Пожаловаться на содержимое документа