WO2002068894A1

WO2002068894A1 - Weapon adapter with modified hammer control mechanism

Info

Publication number: WO2002068894A1
Application number: PCT/CZ2002/000009
Authority: WO
Inventors: Jaroslav Precechtel; Milan Holy
Original assignee: Cz Strakonice, A.S.
Priority date: 2001-02-15
Filing date: 2002-02-15
Publication date: 2002-09-06
Also published as: CZ2001596A3

Abstract

The invention involves a weapon adapter that contains bolt casing (1) with fixed barrel, and the bolt inside this casing is mounted on guiding rods that are provided with plugs at their ends and where its principle is based on a flat carrier (9) of pulses of hammer release mechanism (12), which is lengthwise slide-mounted in a hole at the bottom part of the casing (1), and modified in its rear part for engagement with the lever (10) of the hammer release mechanism and its front part modified for the engagement with the bottom part of the bolt mechanism (4).

Description

Weapon adapter with modified hammer control mechanism.

Technical Field

The invention concerns firearms, either automatic or semi-automatic, where by a replacement of barrel and bolt mechanism with accessories, a conversion of such weapons to weapons with equal functions but using other, typically lower-calibre, ammunition, is performed. This covers the adapters involving the bolt mechanism with accessories.

Background Art

At present, there are known adapters, which, in case of automatic or semi-automatic weapons, are used for changing of their calibres and that consist of barrel or insertion barrel, bolt mechanism and bolt casing. Other weapon parts remain, for the common use in a weapon modifies in this way, without any modification. Also functions of the existing parts remain either unchanged or, if applicable, not used at all. The construction of parts that are not changed in the conversion, is usually designed without any respect to later modifications and therefore, in a comparison with the original assembly for firing the weapon with the original calibre, the shape and assembly of parts of conversion kits, i.e. the adapters, must involve solutions for some additional problems. The adapter for modification of automatic fire-arm conversion to some lower calibres is shown, for instance, in US Pat. No. 3771415. This involves casing with a bolt, sliding along guiding rods and sprung partly with return springs located between the bolt mechanism and bolt stop end (plugs) at the guiding rod ends and partly with recoil-absorber spring, on which the bolt stop end is leaned. Tuning of spring strain capacities and moving element weights must be then performed in the way keeping the weapon firing abilities under the original modes even after the conversion, where some part weights and shapes are changed owing to ammunition reduced in weight and size. This way some problems emerge and they are connected partly with strain capacities but also with sizes of return springs and partly also with dimensional adjustments of new or modified bolts against its co-operating elements in the unchanged weapon part, particularly in the hammer locking and triggering mechanism. In case of the locking hammer mechanism, the co-operation of bolt and hammer blocking mechanism is often impaired after the weapon conversion by applications of adapters for firing of smaller calibres owing to dimensional modifications to smaller calibre ammunition and/or changed weight of bolt parts and ammunition together with changed recoil values. The problem is that in the automatic mode, the hammer release should be made in the moment when the bolts completes its reverse move forward and the new cartridge is closely before its final engagement into the chamber. The pulse of hammer release mechanism results out of the bolt movement. In cases where a weapon adapter has a lower travel and/or the bolt is shorter, usually due to modifications of return springs, failures in the process of hammer releasing may occur. Possible remedies may involve either some adjustments in the hammer release mechanism or re-working of the whole bolt. However, both procedures may be significantly costly and sometimes difficult in technical viability.

Disclosure of the Invention

Shortcomings of so-far solutions are being remedied to a significant extent and designs of economically affordable and technically fully acceptable adapters for firearms to convert them for firing other calibres are now solved by weapon adapters with modified hammer control, where the adapter contains bolt casing with a fixed barrel and the bolt in the casing is supported by guiding rods provided at their ends with plugs according to the invention, where its principle is in the arrangement of a fiat pulse carrier of hammer release mechanism that is slide-mounted lengthwise in the casing bottom part hole and modified in its rear for the engagement of the hammer release lever, while modified in its front part for the engagement of the bolt bottom part. It is advantageous, if the flat carrier is provided, at its front-part upper surface, with a lug modified to be engaged with the bolt bottom part and, at the same time, if the rear carrier part is provided with a hole modified to support the hammer release lever. Particularly advantageous is the arrangement, where the flat carrier is formed as an elongated horseshoe or fork-shaped body with the hole positioned at its closed end and the lug at its upper surface formed at one of free ends of the fork/horseshoe. Furthermore, it may be also advantageous, if the hole in the rear carrier part is provided with a funnelling end modified at its upper part for guiding of top part of the hammer release lever. Finally, it may be advantageous, if the sliding guides of the flat carrier are formed be longitudinal grooves modified at sides of the elongated casing bottom part hole.

This way leads to the design of adapter that is not only functionally reliable under all firing modes, but also production-cost saving one, because for its optimum functions no further modifications of bolt and/or trigger mechanism are necessary and adjustments, if required, for more different calibres are designable in the section of pulse transmission to the hammer only by a modification of the flat carrier.

Brief Description of Drawings

Below, the submitted invention is explained in detail in a typical design that is illustrated at the drawings enclosed herewith, where, on Fig. 1 a substantial weapon part with the adapter is shown in the vertical lengthwise cross-section, while Fig. 2 contains the vertical lengthwise cross-section of detail of the flat hammer pulse carrier and where the same carrier is shown on Fig. 3 in plan view and, finally, where Fig. 4 shows the same carrier in leftside view.

Mode for Carrying Out the Invention

The weapon adapter consists of bolt casing 1, to which in its front part, the barrel 2 with the chamber and borehole for the alternative ammunition type is fixed. The barrel is fixed to the bolt casing 1 with the screw cap 3, which may form a part of weapon adapter fore-end. The bolt 4 is placed in the casing 1_. The bolt 4 travels along two guiding rods 5 that are built-in the barrel and, in their rear parts to the plug 6 of bolt 4_ casing 1 . Under the bolt 4_and in two grooves 1_1 prepared in the casing J . the flat carrier 9_ of pulses of hammer 12 release is slide-mounted. On its top part, the carrier 9 is provided with the lug 9_1, which projects into the bolt 4_ travel, where the bolt is provided with the lug 4 _. The mutual position of lugs 91..41 is selected so that in the moment of bolt 4_ moving forward, before it contacts the barrel 2, the bolt lug 4 _ leans on the carrier lug 9_1 and force coupling, from the bolt 4_ over the carrier 9 to the lever 10 of the hammer release mechanism 12, is thus created, where the lever 10 intervenes into the hole 92 prepared in the rear part of the carrier 9 . The hole 92 may be, in its bottom part, widened to create a tapered section, which may help to make assembly of the adapter to the weapon easier in some spatial configurations, because the lever 10 is being engaged in the hole 92 with a greater reliability. By another movement of the bolt 4 with the carrier 9, the hammer 12 , over the lever 10, is released and shot initiation is thus enabled. It stands to reason that the bolt 4 movement back is initiated by the shot, while the forward travel is initiated by the return springs 7 and, from the rear position, partially also by the shock-absorber spring 8 acting over this shock- absorber body 81 The assembly functions as follows. After the shot, the bolt 4 moves back as far as to the stop end represented by the shock-absorber body 8_1, where it seats over the plug 6 or its accessories, if applicable. Now the empty cartridge is ejected and new round inserted from the magazine, whereupon the bolt 4 travels forward as driven mainly by the return springs 7 and before its seating to the barrel 2, carrier 9 moves ahead by the interaction of the lugs 4_1 and 9_1 to release the hammer 12_ acting to the lever 10 over the hole 92. The hammer j2, through rotation caused by its own spring, hits the firing pin 13, by which the new shot is initiated and firing cycle in the automatic mode may be repeated.

This way a reliable action of transmitting the bolt reverse travel to the hammer release lever is achieved without any difficult modifications of the bolt mechanism in similar built-in adapter systems or re-working of construction of trigger lever systems.

Industrial Applicability

The gear according to this invention is usable in production and operation of firearms, in particular of automatic and semi-automatic types, where, through replacement of some parts within the framework of the adapter, the weapon calibre is changed, while the capacity to fire the weapon in single shots or on automatic is to be preserved.

Claims

1. The weapon adapter with modified hammer control, containing bolt casing with fixed barrel, bolt inside the casing and mounted on two guiding rods that are provided with plugs at their ends, ch a racteris ed i n, that in the hole made in the bottom casing (1) part of the bolt (4), there is the flat impulse carrier (9) of hammer (12) release mechanism and this carrier is slide-mounted and modified, in its rear part, for engagement with the lever (10) of hammer (12) release mechanism, while in its front part, the carrier (9) is modified for engagement in the bottom part of bolt (4).

2. The weapon adapter according to Claim 1, characterised in, that the flat carrier (9) is provided at its front part upper surface by the lug (91), which is modified for engagement with the bolt (4) bottom part and, at the same time, there is prepared the hole (92) in the rear part of this carrier (9) modified to support the lever (10) of hammer (12) release mechanism.

3. The weapon adapter according to Claims 1 and 2, character^'!- s e d i n, that the flat carrier (9) is formed as an elongated horseshoe or fork-shaped body with the hole (92) positioned at its closed end and the lug (91 ) at its upper surface formed at one of free ends of the fork/horseshoe.

4. The weapon adapter according to Claims 1 to3, characteri- s e d i n, that the hole (92) in the rear part of the carrier (9) is provided toward its bottom surface with a slope modified for guiding the upper part of lever (10) of the hammer release mechanism (12).

5. The weapon adapter according to Claims 1 to4, cha racte ri- s e d i n, that the sliding guides of the flat carrier (9) are formed by longitudinal grooves (11), modified at sides of the elongated hole in the bottom part of the bolt (4) casing (1).