Automatic bolt hold-open assembly

Ordnance – Automatic – Firing device operation or control

Reexamination Certificate

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

C089S128000, C089S143000, C042S016000, C042S017000, C042S021000, C042S070020

Reexamination Certificate

active

06510778

ABSTRACT:

BACKGROUND OF THE INVENTION
(a) Field of the Invention
The present invention relates to an automatic bolt hold-open rotating assembly to convert a manual bolt hold-open function to an automatic bolt hold-open function in automatic and semi-automatic pistols and rifles, such as the Ruger 10/22 semi-automatic .22 caliber rifle. The components of the assembly readily replace standard factory components in the trigger assembly and replace the standard magazine. The assembly comprises a magazine with channel cutout, a bolt stop, a bolt stop handle for manual manipulation of the assembly, a bolt stop spring to apply clockwise pressure on assembly, a cartridge detecting lever which also serves as a cartridge ejector pivotably mounted on bolt stop with an extension which interfaces with channel cutout of magazine, a tab protruding from the ejector lever which rides in a slot on the bolt stop to limit pivoting of the cartridge detecting lever, and a lever spring allowing counter-clockwise pivoting of cartridge detecting lever to facilitate insertion of recharged magazine.
In the field of automatic rifles and pistols, most bolts are held open automatically upon discharging the last cartridge in the magazine. Most systems rely on the presence of specially designed magazine followers to hold the bolt open, particularly where magazines contain cartridges in a straight axis. Holding the bolt open allows a simple reinsertion of a freshly charged magazine and a simple means of loading a cartridge into the chamber and closing the bolt on the cartridge either by manipulating a lever or by pulling the bolt rearward and releasing. Keeping the bolt held open after the last shot also eliminates undesirable dry-firing and allows thee chamber to be easily inspected for the presence of a cartridge. This is generally held to be safer when operating automatic firearms.
The bolt hold-open assembly of the present invention operates to hold open the bolt of a firearm after the last cartridge has been discharged from the preferably rotary magazine by automatically rotating into position to hold the bolt open when the last cartridge has been ejected. The assembly of the present invention eliminates the need for specially designed magazine followers.
(b) Description of the Prior Art
U.S. Pat. No. 3,446,114 to W. Ketterer teaches a trigger mechanism for automatic firearms employing a hammer firing device, having a means for converting both from semi-automatic to full-automatic firing and, simultaneously, from closed bolt to open bolt operation, including a catch lever, which, when the firearm is in an automatic firing mode, projects into the passive movement of the breech block, catching and holding the breech block in its rearward position, and further including a driving member for displacing the catch lever from its normal position.
U.S. Pat. No. 3,688,640 to Seecamp teaches a bolt-open latch for a repeating firearm where the bolt-open latch becomes operable by movement of a cartridge carrier beyond its cartridge-feeding position, in order to latch the breech-bolt in an open position when no cartridge is available to be fed into the chamber.
U.S. Pat. No. 3,846,928 to Ruger et al. teaches a bolt lock means comprised of a longitudinally disposed bolt lock lever pivotally mounted on the side of the cartridge receiver and having a magazine follower engaging arm at the forward end thereof and a bolt stop arm at the rearward end thereof.
U.S. Pat. No. 4,057,003 to Atchisson teaches an open-bolt firing conversion for the standard M16 rifle, which allows the rifle to be converted to open-bolt firing by replacement of parts.
U.S. Pat. No. 4,455,919 to Osborne et al. teaches an action disabling device in a firearm in the form of an operating arm pivotable in and out of the closing path of the breech bolt to stop the breech bolt on partial closure of the same whereby the operating arm pivots when engaged by the cartridge lifter during overtravel of the lifter in lift direction for lack of a cartridge thereon.
U.S. Pat. No. 4,697,495 to Beretta teaches a tripping mechanism for the conversion of automatic rifles of the closed-bolt to the open-bolt type, to allow the selection of either single firing or automatic fire. The components are premounted within a box-like support which is readily insertable in the trip box of a conventional automatic rifle.
SUMMARY OF THE INVENTION
The present invention relates to an automatic bolt hold-open rotating assembly to convert a manual bolt hold-open function to an automatic bolt hold-open function in automatic and semi-automatic pistols and rifles, such as the Ruger 10/22 semi-automatic .22 caliber rifle. The components of the assembly readily replace the standard magazine and standard factory components in the trigger assembly, generally identified by manufacturers as follows: bolt lock, ejector, bolt lock spring, and ejector pin. All parts of the present invention are easily installed, and the invention can be easily removed and the firearm easily converted back to its original factory form.
The present invention is designed-to provide an automatic bolt hold-open function in the Ruger 10/22 semi-automatic .22 caliber rifle, in addition to other pistols and rifles. This Ruger rifle functions as follows when a loaded magazine is inserted: The bolt is retracted by manual retraction of the bolt handle. Retracting the bolt cocks the hammer and compresses the recoil spring. Manually releasing the bolt from its retracted position allows the bolt to move forward, driven by decompression of the recoil spring. As the bolt moves forward, it removes a cartridge from the magazine and pushes it forward of the magazine into the gun chamber. The bolt is held against the head of the chambered cartridge by the remaining compression of the recoil spring. Retraction of the trigger releases the cocked hammer, which strikes the rear of the firing pin. The front end of the firing pin is forced forward into the head of the cartridge casing. The firing pin indents the rim of the cartridge case and ignites the priming compound inside the rim. The ignited priming compound ignites the gun powder in the cartridge case, instantly generating a large volume of gas. The gas exerts pressure on the interior of the cartridge case, forcing the bullet out of the cartridge case and down the bore. The gas also exerts pressure on the cartridge casing head, which is in contact with the bolt. This pressure causes the bolt to move rearward. As the bolt retracts, a hook shaped extractor located on an inside wall of the clearance groove in the bolt bottom extracts the spent cartridge case from the chamber and draws the cartridge back across the upper surface of the magazine. As the cartridge is drawn rearward by the bolt, the cartridge head collides with an ejector tab which projects upward from a side of the magazine surface, interrupting the rearward path of the spent cartridge case. The impact of the cartridge case against the ejector tab pushes the cartridge case to the opposed side, away from the ejector tab, and ejects the cartridge case from the chamber. In a firearm designed for right-handed firing, the hook shaped extractor is located on the right inside wall of the clearance groove and the ejector tab projects upward from the left upper surface of the magazine so that the spent cartridges are ejected to the right, away from the face and body of the user. Likewise, in a firearm designed for left-handed firing, the hook shaped extractor is located on a the left inside wall of the clearance groove and the ejector tab projects upward from the right upper surface of the magazine so that the spent cartridges are ejected to the left.
As the bolt continues on its rearward path, it also recocks the hammer and recompresses the recoil spring. After completing its rearward travel, the bolt is then automatically forced forward by decompression of the recoil spring, again stripping a cartridge from the magazine and feeding the cartridge into the chamber. This cycle is repeated each time the trigger is pulled until there are no

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Automatic bolt hold-open assembly does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Automatic bolt hold-open assembly, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Automatic bolt hold-open assembly will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-3025651

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.