Monolithic Projectile with Deformable Jacket for Barrel Wear Reduction
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Solution Overview
Problem
Current small arms ammunition causes excessive barrel wear due to high friction and deformation during firing, limiting barrel life, accuracy, and penetrative performance, especially when using steel cores which are not readily deformable.
Innovation Solution
A projectile design featuring a monolithic body with high Vickers Hardness and strategically located bands, surrounded by a deformable gilding metal jacket, which deforms to fit the rifling grooves, reducing engraving force and preventing propellant gas escape, while maintaining hardness for effective penetration.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If steel core is used to improve penetrative performance, then hardness and penetration capability are improved, but barrel wear increases due to lack of deformability
Solution Approach 1:
The invention uses a composite structure with a hard steel core (providing penetrative performance) enclosed in a soft gilding metal jacket (reducing barrel wear). The jacket material is specifically selected to be readily deformable while the core maintains high hardness for effective penetration against hardened targets.
Solution Approach 2:
Different parts of the projectile have different material properties: the core is made of hard steel for penetration, while the jacket is made of soft, deformable gilding metal for barrel compatibility. This local differentiation allows each component to optimize its function without compromising the other.
2Duration of action of stationary object
If soft, readily deformable materials are used to reduce barrel wear, then barrel life is increased, but penetrative performance decreases
Solution Approach 1:
The composite structure combines soft jacket material (for reduced barrel wear and increased barrel life) with a hard steel core (for maintained penetrative performance). The core ensures that penetration capability is not compromised despite using softer jacket materials.
3Strength
If steel tip and lead core are used separately, then penetrative performance is improved, but trajectory stability deteriorates due to different trajectories at oblique angles
Solution Approach 1:
The invention merges the steel core and gilding metal jacket into a single integrated projectile structure where the core is enclosed within the jacket. This unified structure ensures both components follow the same trajectory, maintaining stability while retaining the penetrative benefits of steel.
4Object-affected harmful factors
If deformable jacket is used to reduce engraving force, then barrel wear is reduced, but sealing effectiveness may be compromised
Solution Approach 1:
The jacket is designed with specific dimensional parameters (outer diameter substantially equal to internal diameter of barrel defined by lands) and material properties (readily deformable) that enable it to dynamically adapt during firing. The deformable jacket creates an interference fit with the rifling lands, providing both reduced engraving force and effective sealing.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The design significantly reduces barrel wear, increases muzzle velocity, and enhances penetrative performance, achieving improved accuracy and lethality against hardened targets without compromising accuracy.
Implementation Method 1
the deformable jacket is deformed by the lands of the rifling in the barrel into the grooves formed between the at least three bands and point of intersection on the elongate core
Implementation Method 2
This provides the advantage of cheap construction, but still provides for a substantial amount of lead. The problem here is that when the projectile strikes a target at an oblique angle
Implementation Method 3
the projectile must deform as it travels along the barrel so that material forming part of the projectile is forced into the spaces between the lands that form the rifling. This process is called engraving, and causes a spin to be imparted to the projectile by virtue of the twist of the rifling
Implementation Method 4
the high linear acceleration imparted by the gun propellant on firing
Implementation Method 5
hardness is a very desirable characteristic for the bullet material, in order to minimise nose tip ablation during penetration of hardened targets such as, for example, titanium/kevlar body armour
Data Source
Figure 1~2
Figure 2a~3
AI summary
This invention relates to a combination of a gun having a rifled barrel and a round of enhanced performance ammunition, and to a projectile for use in the combination. The invention is especially, but not exclusively related to an improved form of projectile for small arms ammunition.There is provided a projectile with a nominal calibre, for use in a rifled barrel, the projectile comprising: a monolithic body, said monolithic body comprising a.an ogival portion forming the front of the monolithic body; said ogival portion at a point of intersection abuts with b.an elongate cylindrical core, said elongate cylindrical core comprising at least three bands located circumferentially thereon, said bands protruding radially outward therefrom; and said elongate cylindrical core abuts c.a boat tailed portion, forming the rear of the monolithic body, wherein a first band is located at the point where the elongate cylindrical core abuts the boat tail section, wherein a third band is located rearwardly, from the point of intersection,at a distance in the range of from 80% to 120% of said nominal calibre, wherein a second band is located between the first and third bands on said elongate cylindrical core; wherein the monolithic body is formed from a metal having a Vickers Hardness of at least 550HV, wherein a deformable jacket or coating, surrounds the monolithic body, which defines an outer diameter of said projectile.