(19) TZZ ¥ _T (11) EP 2 663 826 B1 (12) EUROPEAN PATENT SPECIFICATION (45) Date of publication and mention (51) Int Cl.: of the grant of the patent: F41A 3/26 (2006.01) F41A 3/64 (2006.01) 16.05.2018 Bulletin 2018/20 F41A 3/70 (2006.01) F41A 3/84 (2006.01) F41A 3/72 (2006.01) F41A 5/18 (2006.01) (2006.01) (2006.01) (21) Application number: 12701610.3 F41A 5/26 F41A 11/00 F41A 5/24 (2006.01) F41A 17/64 (2006.01) F41A 17/00 (2006.01) F41A 19/10 (2006.01) (22) Date of filing: 13.01.2012 F41A 19/42 (2006.01) F41A 15/14 (2006.01) F41A 19/13 (2006.01) (86) International application number: PCT/US2012/021368 (87) International publication number: WO 2012/097334 (19.07.2012 Gazette 2012/29) (54) FIREARM FEUERWAFFE ARME À FEU (84) Designated Contracting States: (74) Representative: Freeman, Jacqueline Carol AL AT BE BG CH CY CZ DE DK EE ES FI FR GB WP Thompson GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO 138 Fetter Lane PL PT RO RS SE SI SK SM TR London EC4A 1BT (GB) (30) Priority: 14.01.2011 US 201161433115 P (56) References cited: 16.08.2011 US 201161524138 P EP-A1- 0 055 690 EP-A1- 1 479 997 EP-A1- 1 596 151 EP-A2- 2 045 561 (43) Date of publication of application: CH-A- 37 247 CH-A- 199 224 20.11.2013 Bulletin 2013/47 DE-A1- 3 707 925 DE-A1-102007 034 670 FR-A- 1 362 361 GB-A- 166 579 (73) Proprietor: Armwest, LLC GB-A- 525 429 GB-A- 604 348 Prescott, Arizona 86305 (US) US-A- 1 588 887 US-A- 1 907 164 US-A- 1 946 388 US-A- 2 088 268 (72) Inventors: US-A- 2 096 028 US-A- 2 365 306 • SULLIVAN, Leroy James US-A- 2 376 466 US-A- 2 462 119 Prescott, Arizona 86305 (US) US-A- 2 482 880 US-A- 2 756 640 • WATERFIELD, Robert Lloyd US-A- 2 910 332 US-A- 3 090 148 Prescott, Arizona 86303 (US) US-A- 3 090 149 US-A- 3 330 183 • OSTROWSKI, Alan H. US-A- 3 346 982 US-A- 3 366 011 Prescott, Arizona 86305 (US) US-A- 3 795 173 US-A- 3 990 348 • LATULIPPE, JR., Paul N. US-A- 5 448 940 US-A- 5 909 002 Chino Valley, Arizona 86323 (US) US-A1- 2005 262 752 US-A1- 2008 092 733 • EYSSAUTIER, Hyunjung Samuel US-A1- 2010 095 833 US-B1- 6 829 974 Prescott, Arizona 86303 (US) US-B1- 8 316 756 Note: Within nine months of the publication of the mention of the grant of the European patent in the European Patent Bulletin, any person may give notice to the European Patent Office of opposition to that patent, in accordance with the Implementing Regulations. Notice of opposition shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention). EP 2 663 826 B1 Printed by Jouve, 75001 PARIS (FR) 1 EP 2 663 826 B1 2 Description [0007] The document EP1479997 (A1) discloses a rifle which has a stock and a removable barrel. The stock has TECHNICAL FIELD a stock housing and a recess for the barrel. The barrel has at least one pin. The recess has an aperture for the [0001] One or more of the embodiments relate gener- 5 pin. There is a groove round the pin. A locking device ally to firearms, and more particularly for example, to a acts with the groove. The extent to which the pin projects firearm configured to facilitate a quick barrel change and from the barrel may be adjustable. having features which enhance the reliability thereof. BRIEF SUMMARY BACKGROUND 10 [0008] A firearm according to the invention is defined [0002] Semi-automatic and fully automatic firearms by the wording of claims 1 - 15. are well known. Semi-automatic firearms shoot one bullet [0009] In accordance with embodiments further de- each time that the trigger is pulled. Fully automatic fire- scribed herein, features are provided that may be advan- arms continue shooting as long as the trigger is pulled 15 tageously used in one or more firearm designs. Some of and they have not exhausted their ammunition. Fully au- these embodiments are covered by the claims and form tomatic firearms are typically capable of relatively high part of the present invention whereas other embodiments rates of fire, i.e., cyclic rates. For example, the M16 and are not covered by the claims and hence do not form part the M4 have a nominal cyclic rate of 700 to 950 rounds of the present invention. According to an embodiment, a per minute. 20 firearm canhave a backbone, abarrel, aswinging wedge, [0003] Because fully automatic firearms are capable and a barrel latch. The barrel latch can be in mechanical of such high cyclic rates, they are prone to a variety of communication with the swinging wedge such that mov- problems. For example, sustained fully automatic fire can ing the barrel latch will move the swinging wedge. The result in barrel overheating. Barrel overheating is partic- barrel latch can have a first position and a second position ularly problematic when high capacity magazines, such 25 and the swinging wedge can be configured to maintain as SureFire’s 60 round and 100 round magazines, are attachment of the barrel to the backbone when the barrel being used. High capacity magazines allow longer peri- latch is in the first position and can be configured to re- ods of sustained fire since fewer magazine changes are lease the barrel from the backbone when the barrel latch required to fire a given number of rounds. Fewer maga- is in the second position. zine changes provide less time for the barrel to cool.30 [0010] According to an embodiment, a firearm can Thus, the barrel, as well as other parts of the firearm, can have a bolt carrier, a backbone configured to guide the be subjected to increased heat. bolt carrier, a lower receiver within which the bolt carrier [0004] Often, the ability to keep firing is limited by barrel is at least partially disposed wherein the barrel is attached overheating. When the barrel of a firearm overheats, ac- to the backbone, a barrel latch attached to the backbone, curacy of the firearm is substantially reduced. Further 35 a barrel configured to disengage from the backbone overheating of the barrel can result in malfunction of the when the barrel latch is pushed, a trigger block assembly firearm. For example, cartridges chambered into an over- configured to drop into the lower receiver, a gas piston heated barrel can detonate prematurely, i.e., cook off, having a plurality of piston rings configured to only rotate particularly in closed bolt firearms. If the barrel is over- substantially in unison with one another, an operating rod heated sufficiently it can deform, thereby resulting in a 40 configured to move in response to movement of the gas catastrophic failure of the firearm. piston and configured to move the bolt carrier when a [0005] Even after the barrel has returned to an accept- cartridge is discharged, a metered gas port disposed out able operating temperature, the firearm may be unusa- of the barrel for metering gas from the barrel to the gas ble. The barrel and/or other components of the firearm piston,a springguide having a main spring disposed ther- may have been permanently damaged. Changing the 45 eon for biasing the bolt carrier in a forward position, an barrel of a contemporary firearm such as the M16 or M4 anti-bounce weight at least partially contained within the takes a substantial amount of time and is not generally spring guide, a bolt carried by the bolt carrier, an extractor performed in the field. When the firearm is unusable due attached to the bolt, two springs disposed within the bolt to overheating and while the barrel is being changed, a for biasing the extractor toward a closed position of the soldier or police officer cannot shoot the firearm and is 50 extractor, a bar inhibiting separation of the lower receiver thus undesirably vulnerable to attack. and the backbone when the main spring is compressed, [0006] The inability to shoot a firearm can have disas- a firing pin disposed within the bolt, a firing pin retaining trous consequence in battlefield and police situations. pin configured to facilitate removal of the firing pin and The inability to shoot has resulted in loss of life in such configured to transfer forward movement of the bolt car- instances. Therefore, it is desirable to provide systems 55 rier to the firing pin to cause a cartridge to fire, a hammer for facilitating the quick change of the barrel of a firearm assembly disposed within the lower receiver and having and for otherwise enhancing the reliability and utility of a hammer and a link with one end of the link attached to the firearm, for example. the hammer and another end of the link attached to the 2 3 EP 2 663 826 B1 4 lower receiver such that the hammer has a rearward po- barrel latch,and a pin attached tothe barrel. The swinging sition that is below the bolt when the bolt is in a rearward wedge can be configured to facilitate attachment of the position and the hammer has a forward position where barrel to the backbone via the pin such that moving the the hammer strikes the firing pin when the bolt is in a barrel latch allows the barrel to detach from the back- forward position and wherein the link is configured such 5 bone.