Firearm

A locked breech mechanism for a firearm having a trigger, cylinder, and hammer and in which the cylinder is adapted to accommodate cartridges such as a bottleneck cartridge. The breech mechanism includes a breech member disposed between the hammer and cylinder in combination with an operating member. The breech operating member is in the form of a yoke member having a rest position in which the breech member is disengaged from a cartridge in the cylinder, and an active position in which the breech member is engaged with and locked against the cartridge.

What is claimed is:

1. A firearm comprising;

a frame,

a trigger,

means mounting the trigger in the frame,

a cylinder mounted in the frame and having a plurality of cartridge-accommodating passages,

a hammer also mounted in the frame and responsive to trigger action,

a breech member,

means supporting the breech member in the frame disposed between the hammer and cylinder,

breech operating means,

and means supporting the breech operating means in the frame disposed operatively between the trigger and breech member,

said breech operating means having a rest position in which said breech member is disengaged from a cartridge in said cylinder, and an active position in which said breech member is engaged with and locked against the cartridge,

said breech operating means comprising a cam integral with said trigger and an elongated cam follower responsive to cam rotation coincident with trigger rotation for causing said cam follower to engage and slide said breech member toward engagement with the cartridge.

2. A firearm as set forth in claim 1 including a first spring engageable with said cam follower for urging the cam follower into contact with the cam carried by the trigger.

3. A firearm as set forth in claim 2 wherein said cam has a low radius engaging the cam follower in the rest position and a high radius engaging the cam follower in the active position.

4. A firearm as set forth in claim 3 wherein said cam follower comprises a yoke member, said frame having a vertically extending groove for receiving said yoke member in sliding relation therein.

5. A firearm as set forth in claim 4 wherein said breech member has means defining a ramp against which the top of the yoke member rides.

6. A firearm as set forth in claim 5 including at least one pin fixed in the frame, the top of the yoke member adapted to be urged between said pin and ram to move said breech member.

7. A firearm as set forth in claim 6 including a second spring acting directly on the breech member to return the breech member to a rest position spaced from the cartridge.

8. A firearm as set forth in claim 7 wherein said breech member has opposed flats for receiving said yoke member and further including a pair of pins supported from the frame and extending respectively into the opposed flats.

9. A firearm as set forth in claim 8 wherein said first spring is supported at one end in the frame and at the other end in the yoke of the yoke member.

10. A firearm as set forth in claim 9 including a firing pin supported in said breech member.

11. A firearm as set forth in claim 1 including pin means fixed in the frame, said cam follower having a top end that engages between said pin means and a surface of said breech member for moving said breech member relative to said pin means.

12. A firearm as set forth in claim 11 wherein said breech member has a ramped surface against which the top end of the cam follower engages.

13. A firearm as set forth in claim 1 wherein said cam follower comprises an elongated member having a bottom end engaging the cam and a top end adapted to moved said breech member.

14. A firearm as set forth in claim 13 including a link means supported at the top end of the cam follower and having a locked position when the breech member is moved to its active position and having a partially folded position when the breech member is at its rest position.

15. A firearm as set forth in claim 15 wherein the link means includes a pair of links commonly connected at one end to the top end of the cam follower.

16. A firearm as set forth in claim 15 including means securing the opposite end of one link to the breech member and the opposite end of the other link to the frame.

17. A firearm as set forth in claim 16 wherein said cam follower comprises a yoke member.

18. A firearm as set forth in claim 17 wherein said breech member has opposed recesses forming opposed flats for receiving said yoke member.

19. A method of engaging and locking a breech member against a cartridge that is supported in a cylinder which in turn is supported in a firearm frame, said firearm furthermore including trigger means for firing said firearm and a hammer means adapted, upon firing, to impact a firing pin, said method comprising the steps of, supporting said firing pin by means of the breech member, providing a breech operating means, supporting said breech operating means in a position responsive to said trigger means for moving said breech member from a rest position in which said breech member is disengaged from the cartridge and corresponding to a rest position of the trigger means, to an active position in which said breech member is engaged with said cartridge and corresponding to an active position of the trigger means, maintaining the breech member locked against said cartridge in preparation for firing when the hammer means impacts the firing pin,

providing a fixed member secured to the frame and urging the breech operating means between the fixed member and breech member to move and lock the breech member against the cartridge, and

providing a ramp on the breech member for engagement by the breech operating means.

20. The method as set forth in claim 19 including providing a cam operable from said trigger for urging the breech operating means into operative engagement on said ramp.

21. In a firearm having a frame, a cylinder for accommodating cartridges, a trigger and hammer, the improvement comprising, a breech member, means supporting the breech member in the frame disposed between the hammer and cylinder, breech operating means, and means supporting the breech operating means in the frame disposed operatively between the trigger and breech member, said breech operating means having a rest position in which said breech member is disengaged from a cartridge in said cylinder and an active position in which said breech member is engaged with and locked against the cartridge, said breech operating means comprising a cam integral with said trigger and an elongated cam follower responsive to cam rotation coincident with trigger rotation for causing said cam follower to engage and slide said breech member toward engagement with the cartridge.

22. A firearm as set forth in claim 21 wherein said cam follower comprises a yoke member, said frame having a vertically extending groove for receiving said yoke member in sliding relation therein.

23. A firearm as set forth in claim 22 including a first spring in engagement with said cam follower for urging the cam follower into contact with the cam, said cam having a low radius engaging the cam follower in the rest position and a high radius engaging the cam follower in the active position, said breech member having means defining a ramp against which the top of the yoke member rides, and a second spring acting directly on the breech member to return the breech member to a rest position spaced from the cartridge.

24. In a firearm having a frame, a cylinder for accommodating cartridges, a trigger and a hammer, the improvement comprising, a breech member, means supporting the breech member in the frame disposed between the hammer and cylinder, breech operating means, means supporting the breech operating means in the frame disposed operatively between the trigger and breech member, said breech operating means having a rest position in which said breech member is disengaged from a cartridge in said cylinder and an active position in which said breech member is engaged with and locked against the cartridge, a cam operable from said trigger, said breech operating means comprising a cam follower responsive to cam rotation for causing said cam follower to engage and move said breech member from its rest position to its active position.

25. A firearm as set forth in claim 24 including a ramp provided on the breech member for engagement by the cam follower.

26. A firearm as set forth in claim 25 wherein said cam follower comprises a yoke member and said breech member has opposed recesses for receiving said yoke member.

27. A firearm as set forth in claim 26 including a first spring and engagement with said cam follower for urging the cam follower into contact with the cam, said cam having a low radius engaging the cam follower in the rest position and a high radius engaging the cam follower in the active position, and a second spring acting on the breech member to return the breech member to a rest position spaced from the cartridge.

28. A firearm as set forth in claim 24 further including a pair of links commonly connected to the cam follower and having opposed ends respectively connected to the frame and breech member, said links being in a substantially linearly aligned position when the operating member is the active position.

29. A firearm as set forth in claim 28 wherein the pair of links are moved to a folded position in the rest position of the breech operating means.

30. In a firearm having a frame, a cylinder for accommodating cartridges, a trigger and hammer, the improvement comprising, a breech member, means supporting the breech member in the frame disposed between the hammer and cylinder, breech operating means, means supporting the breech operating means in the frame disposed operatively between the trigger and breech member, said breech operating means having a rest position in which said breech member is disengaged from a cartridge in said cylinder and an active position in which said breech member is engaged with and locked against the cartridge, said breech operating means including an operating member responsive to trigger action, and a pair of links commonly connected to the operating member and having opposed ends respectively connected to the frame and breech member, said links being in a substantially linearly aligned position when the operating member is in the active position of the breech operating means so as to lock the breech member against the cartridge.

31. A firearm as set forth in claim 30 including a cam operable from said trigger and wherein said operating member comprises a cam follower responsive to cam rotation for causing said cam follower to operate said breech member.

32. A firearm as set forth in claim 31 wherein said operating member comprises a yoke member.

33. A firearm as set forth in claim 32 wherein said breech member has opposed surfaces each carrying a pair of links supported on either side from said yoke member.

34. A firearm as set forth in claim 33 including a first spring in engagement with said yoke member for urging the yoke member into contact with the cam, said cam having a low radius engaging the cam follower in the rest position and a high radius engaging the cam follower in the active position, and a second spring acting on the breech member to return the breech member to a rest position spaced from the cartridge.

35. A firearm as set forth in claim 30 wherein said pair of links is moved to a folded position out of linear alignment when the operating member is in the rest position.