GB1581779A

GB1581779A - Spin stabilized projectile

Info

Publication number: GB1581779A
Application number: GB3436577A
Authority: GB
Original assignee: Rheinmetall GmbH
Current assignee: Rheinmetall Industrie AG
Priority date: 1976-09-20
Filing date: 1977-08-16
Publication date: 1980-12-17
Also published as: SE7709966L; FR2365097A1; IT1086134B; DE2642187A1; CA1094387A

Description

(54) A SPIN STABILIZIED PROJECTILE (71) We, RHEINMETALL Gesellschaft mit beschränkter Haftung, of Ulmenstrasse 125, 4 Dusseldorf 1, German Federal Republic, a Company organised and existing under the laws of the German Federal Republic, do hereby declare the invention for which we pray that a Patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to a spin stabilized projectile of annular construction having a propulsive base bearing against the rear end of the projectile and connected therewith whereby, after the cartridge charge has been fired the base and the projectile separate after leaving the barrel of the weapon.

According to this invention there is provided a spin stabilized annular projectile having a propulsive base bearing against the rear end of the projectile and connected thereto through a joint which holds during normal handling but which breaks due to shear forces occurring on firing due to spin acceleration imparted by the barrel and acting through a guide ring on the projectile.

With such a connection between the projectile and the base, the projectile is particularly simple and light weight requiring no special machining operations over and above the usual machining required for projectiles. The separation of the projectile and the base is generally reliable, since after the projectile has been fired the projectile and the base are no longer in any way mechanically connected, even when still in the barrel. Due to the rapid braking of the base by air resistance no further parts which may induce jump errors are separated froin the projectile.

The projectile due to the moderate overall weight for a given propulsive charge may have a very high initial velocity enabling a long flat trajectory to be obtained.

An embodiment according to the invention is shown by way of example in the accompanying drawing which is a longitudinal section.

As shown a projectile 2 is of annular form with a conical tapered part 2b and a cylindrical bore 2c and bears through an end surface 2a against a shoulder 6a of a propulsive base 6. The projectile 2 has a barrel guide ring 4 of sintered iron positioned in a peripheral groove.

Between the end 2a and shoulder 6a is provided a jointing agent or adhesive which gives a reliable joint for handling purposes between the projectile 2 and the base 6, but which is broken as a result of the shear force occurring during spin acceleration when the projectile is fired. These shear forces occur because only the projectile 2 has a guide ring 4, so that the twist is only transmitted through the projectile 2. The base 6, due to rotational inertia, tends to lag behind the twist imparted to the projectile 2.

The joint between the projectile and the base is sheared whilst both are still within the barrel of the weapon so that the base 6 separates from the projectile 2 as soon as they both leave the barrel. To prevent the end 2a and shoulder 6a from binding or seizing, the adhesive has anti-seizing or anti-binding properties. The jointing agent may be soft solder.

Due to friction between the contact surfaces of the projectile 2 and the base 6 after the soft-soldered joint has sheared, the solder melts and acts as a lubricant between the two parts to prevent binding or seizing between the surfaces of the parts. If the projectile 2 and the base 6 are interconnected by an adhesive, then this should also have anti-binding and anti-seizing properties. This can be achieved by the addition of suitable compounds to the adhesive.

WHAT WE CLAIM IS: 1. A spin stabilized annular projectile

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. (54) A SPIN STABILIZIED PROJECTILE (71) We, RHEINMETALL Gesellschaft mit beschränkter Haftung, of Ulmenstrasse 125, 4 Dusseldorf 1, German Federal Republic, a Company organised and existing under the laws of the German Federal Republic, do hereby declare the invention for which we pray that a Patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to a spin stabilized projectile of annular construction having a propulsive base bearing against the rear end of the projectile and connected therewith whereby, after the cartridge charge has been fired the base and the projectile separate after leaving the barrel of the weapon. According to this invention there is provided a spin stabilized annular projectile having a propulsive base bearing against the rear end of the projectile and connected thereto through a joint which holds during normal handling but which breaks due to shear forces occurring on firing due to spin acceleration imparted by the barrel and acting through a guide ring on the projectile. With such a connection between the projectile and the base, the projectile is particularly simple and light weight requiring no special machining operations over and above the usual machining required for projectiles. The separation of the projectile and the base is generally reliable, since after the projectile has been fired the projectile and the base are no longer in any way mechanically connected, even when still in the barrel. Due to the rapid braking of the base by air resistance no further parts which may induce jump errors are separated froin the projectile. The projectile due to the moderate overall weight for a given propulsive charge may have a very high initial velocity enabling a long flat trajectory to be obtained. An embodiment according to the invention is shown by way of example in the accompanying drawing which is a longitudinal section. As shown a projectile 2 is of annular form with a conical tapered part 2b and a cylindrical bore 2c and bears through an end surface 2a against a shoulder 6a of a propulsive base 6. The projectile 2 has a barrel guide ring 4 of sintered iron positioned in a peripheral groove. Between the end 2a and shoulder 6a is provided a jointing agent or adhesive which gives a reliable joint for handling purposes between the projectile 2 and the base 6, but which is broken as a result of the shear force occurring during spin acceleration when the projectile is fired. These shear forces occur because only the projectile 2 has a guide ring 4, so that the twist is only transmitted through the projectile 2. The base 6, due to rotational inertia, tends to lag behind the twist imparted to the projectile 2. The joint between the projectile and the base is sheared whilst both are still within the barrel of the weapon so that the base 6 separates from the projectile 2 as soon as they both leave the barrel. To prevent the end 2a and shoulder 6a from binding or seizing, the adhesive has anti-seizing or anti-binding properties. The jointing agent may be soft solder. Due to friction between the contact surfaces of the projectile 2 and the base 6 after the soft-soldered joint has sheared, the solder melts and acts as a lubricant between the two parts to prevent binding or seizing between the surfaces of the parts. If the projectile 2 and the base 6 are interconnected by an adhesive, then this should also have anti-binding and anti-seizing properties. This can be achieved by the addition of suitable compounds to the adhesive. WHAT WE CLAIM IS:

1. A spin stabilized annular projectile having a propulsive base bearing against the rear end of the projectile and connected thereto through a joint which holds during normal handling but which breaks due to shear forces occurring on firing due to spin acceleration imparted by the barrel and acting through a guide ring on the projectile.

2. A projectile in accordance with Claim 1, wherein the projectile rear end engages a shoulder on the base through the joint.

3. A projectile in accordance with Claim 1 or 2, wherein the projectile and the base are interconnected by an adhesive.

4. A projectile in accordance with Claim 1 or 2, wherein the projectile and the base are interconnected by soft-solder.

5. A projectile in accordance with any preceding claim, wherein the joint is adapted to reduce binding or seizing of the surfaces after breaking.

6. An annular projectile constructed and arranged to function substantially as herein described with reference to the accompanying drawings.