UNITED STATES PATENT OFFICE.
J O.HA •] _ OLSEN NYGAARD; O.F CH.RISTIA TIA NORWAY.
ATTACHMENT TO THE 'BARRELS OF FIREARMS.
Specification of Letters Patent. Patented Oct. 9 1908:;

Applination filed September 1 1905. Serial No. 276 741.
To all whom it may eo72cen2r closed position. Fig. 5 is a detail of one of
Be it known that I JOHAN OLSEN Ny- the valves. Fig. 6 is a sectional view of the GAARD a subject `of the King of Sweden and I valve shown in Fig. 5. Figs. 7 and 8 are side 'Norway residing at the city of Christiania and end views of a structural detail.
5 in the Kingdom of Sweden and Norway have Like parts are designated by similar char- 55 inventeda new and useful Attachment to the actors of reference throughout the different Barrels of Firearms 'of which the following is figures of the drawings.

a full clear and exact description. A designates the barrel of the gun provided

The invention relates to improvements in with the usual bore. The exterior of the bar-

0 ordnance 'and has for its object the provision i rel is reduced from the muzzle inwardly a 6o of an improved muffling device for deaden- suitable distance and is provided with exteing the report accompanying the firing of a rior screw-threads.

charge and the invention also has for its ob- I B designates a sleeve internally threaded ject the arrangement of such a device where-

T5 by:smoke and gases accompanying the discharge of the weapon are prevented from is-suing from the muzzle with and subsequent to the passage of the projectile.

According to my invention there is provided

20 mechanical instrumentalities adapted to be acted upon by the gases accompanying the firing of pa charge in a manner to temporarily close the bore of the gun to the outwardly-traveling gases and thereby muffle the re

25 port of the charge.

To this end the invention consists in provid-
ing the barrel with latei v Ive-chambers lo-
cated adjacent the muzzle and commumcat
in with the bore by suitably-disposed dos-
30 able ports and in the provision within the
chambers of valves adapted when seated to
"close the bore said valve-chambers commu-
eating`with. the bore by means of channels
adapted to admit the gases in. a manner to
35 close said valves; the latter being normally
held in an open position. In combination
with the above there may be provided on sta-
tionary ordnance a smoke or gas chamber
adapted to forma receiver for the gases and
40 smoke and connected with an outlet of the mailer.
In the drawings; Figure I is a longitudinal
horizontal section. of a gun showing the de-
vice of my invention applied thereto. Fig. 2
45 is a side elevation of the muzzle end of the
barrel showing the improved smoke and gas
chamber in section. Fig. 3 is a vertical sec-
. tional view on line 4 4 of Fig. 1. Fig. 4 is a
vertical fragmentary end section of the muz-
0 zle end of the barrel showing the valves in
and adapted to fit on the threaded outer end
of the barrel and preferably extendi g 65
throughout the length of the threaded portion thereof. Said sleeve B is provided adjacent the muzzle with laterally-disposed charm' bers C which communicate with the barrel by parts c. The chambers C are provided 70 with oppositely-facing converging surfaces K adapted to form valve-seats which surfaces register with and are continued by inclined faces c' formed in the barrel of the gun the latter surfaces converging to a line c in- 75 tersecting the. axis of the bore. Said valve-seats extend inwardly from the upper and lower walls of the chambers a sufficient distance to form an effective contact-surface
and are centrally recessed at j. 80
Valves D are provided which consist of P at plates of a width substantially equal to ie height of the chambers C and have an operative fit therein. Said valves are provided with trunnions d adapted to seat in recesses 85 b formed in the outer end of the sleeve B. Said valves D are chamfered at their inner ends as' shown at d' at which point said valves engage each other when closed the chamfered surface being of sufficient area. to 90 form an effective contact-surface. In order to maintain the valves normally in an open
position; springs . J - are provided and as shown ; are- seated in the recesses j and an-
chored therein to the sleeve B the free ends of 95. said springs engaging the inner faces of the valves D and normally holding the same in the position shown in Fig. 1.
In order to render the valve-chambers readilyaccessible and in order to enable the zoo
832 685
valves D to be quickly replaced in case of in-jury or for purposes of cleaning the same the sleeve B.is provided with lateral openings or passages b' adapted to be closed by remov-
5 able plates G. Such plates are beveled on their end and lateral margins and have a dovetailed it with the overhanging margins of said openings b'.
I preferably connect the plates G by an
10 end piece F the latter being preferably greater in width than the valves D and their trunnions and adapted to cover the recesses b and hold the trunnions in place therein and likewise to close the outer ends of the valve-
15 chambers C. The end piece F is centrally apertured at f to accommodate the outer muzzle end of the barrel. When the valves D are inserted in place the connecting end piece :F and plate G are inserted in place end-
2o wise of the sleeve B. the plates G closing the openings b'. and the end piece F closing the outer end of the sleeve B and surrounding the barrel 'A as clearly shown in Fig. 1. A. nut II serves to securely hold the parts in an as-
25 sembled position.
The sleeve$ is provided with passages E which communicate at e with the bore at one end and with the chambers Cat their opposite ends and preferably at the outer lateral por=
3o Eons of said chambers and at a point later-ally beyond the normal position of the valves Di as clearly shown in Fig. 1.
The bore' is provided with an outlet 0 for the-gases which may communicate with the outer air or with any suitable form of receiver. Ass u and in cases where the in-' verrtion is 'applied to heavy ordnance the out-let' 0 oonrmumcaAes by a by-pass P'with a smoke-chamber M. Said chamber M consists of a casing provided with a flange m' adapted to fit over the outer end of the sleeve B and to be secured in place thereto in any desired manner. The chamber M is provided with a partition N and with an end wall m2. The partition N is apertured at n and the wall m' at m' to accommodate the projectile.
The operation will be obvious from the forego i-n but may be briefly described as follows : When the charge is fired the accompanying gases after the projectile has passed the point desipated by e pass through the passages E and engage the outer faces of the valves D. By reason of the fact that the valves D substantially fill the valve-chambers the pressure of the incoming gases forces the valves down upon their seats serving to close the bore and prevent the gases issuing from they muzzle. This action serves effectively to muffle the usual report accompany-
6o ing the firing of a charge. The remaining gases are free to pass out through the open-
0 into the chamber M or into any other suitable receiver: The gases accompanying
the projectile and passing out therewith be-fore the valves D are closed are practically 65
all retained in the smoke-chamber M there being no draft to carry off the contents of said chamber.
It will be obvious that'the smoke-chamber
M is not an essential feature of the invention 7o and that it will be used only in connection with heavy ordnance.
It will be further understood that all of the advantages of the invention may be realized by the employment of my improved muffling 75 device-independent of the chamber M as the latter performs no function in muffling the . re ort of the fired charge.
claim-
1. An attachment to the barrel of firearms 8o consisting of a piece securely fixed to the muzzle of the gun and comprising two chambers located one on each side of the bore and containing two clacks which are held in open position by springs and in closed position 85 meet in the center line of the bore said chambers on the one side of the said clacks communicating with the front end of the bore or with an extension of the same and on the other side of the clacks the said chambers 90 communicate with channels branching off from the bore at a point located at a suitable distance from the closing-point of the said clacks substantially as shown. and for the pi pose specified. 95
2. A muffler for ordnance comprising in combination a barrel provided with a bore a sleeve securedto the barrel valve-chambers formed in said sleeve and communicating with. the bore by ports said chambers also ioo communicating with the bore by passages and a plurality of valves located in said chambers and serving when acted upon by the discharging gases to close said bore.
3. A muffler for ordnance comprising in 105 combination a barrel provided with a bore a sleeve secured to the barrel chambers formed in said sleeve. and communicating With said bore by ports said chambers also. communicating with said bore by passages and spring- 110 actuated valves located in said chambers between the terminals of said passages and ports and serving to close said bore when acted upon by the'discharging gases.
4. A muffler for ordnance comprising in 115 combination a barrel provided with a bore two valve-chambers communicating with .said bore said chambers also' communicating with said bore by passages and valves located in said chambers and serving to close 120 said bore when acted upon by discharging gases. .
5. A muffler for' ordnance comprising in. combination a barrel provided with a bore a sleeve secured to the muzzle end of the barrel 125 chambers formed in said sleeves snd co n

5
nicating with said bore by ports said chambers also communicating with said bore by . passages spring-actuated valves located in said chambers between the terminals of said passages and ports and serving to close said bore when acted upon by the discharging gases a smoke-chamber divided into two compartments and having apertures for the
discharge of the projectile and a by-pass leading from said bore to said chamber. o
In testimony whereof I affix my signature in presence of two witnesses.
JOHAN OLSEN NYGAARD. Witnesses:
N. G. FAUDBERG HENRY BoRDEWICH.