Bullet Drag-Reducing Assembly Cavity Choke Annulus

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Solution Overview

Problem

Conventional bullets experience flight instability and reduced precision due to pressure differences on the rearward face, causing drag and affecting accuracy and grouping.

Innovation Solution

The bullet design incorporates a drag-reducing assembly with an internal body cavity and a choke annulus or nozzle component that captures and releases combustion gas to reduce base drag, maintaining perpendicularity and enhancing structural integrity and gyroscopic stability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional bullet design is used, then manufacturing simplicity is maintained, but flight stability and precision deteriorate due to pressure difference drag on the rearward face

Engineering Contradiction:
Improveflight stabilityVSAvoidbullet structure
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The bullet is divided into distinct functional segments: a front ogive-shaped section, a rear cylindrical section, and an integrated drag-reducing assembly at the base. This segmentation allows each part to optimize its function while maintaining overall structural coherence and flight stability.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The drag-reducing assembly is merged with the bullet base, combining the cavity structure, choke annulus, and gas release function into a single integrated component. This merging reduces the number of separate parts while achieving the dual benefit of drag reduction and structural integrity.

Inventive Principle:
Principle #5Merging (Combining)

2Speed

If a drag-reducing assembly with cavity and nozzle is added, then drag is reduced and muzzle velocity increases, but device complexity increases

Engineering Contradiction:
Improvemuzzle velocityVSAvoidbullet structure
Core Design Contradiction:
SpeedVSDevice complexity

Solution Approach 1:

The choke annulus is nested within the drag-reducing assembly cavity, and the gas release pathways are nested within the bullet base structure. This nesting arrangement maximizes functional density while minimizing the overall increase in bullet dimensions and complexity.

Inventive Principle:
Principle #7Nested doll (Nesting)

Solution Approach 2:

The drag-reducing assembly utilizes pneumatic principles by capturing combustion gases in the cavity and releasing them through the choke annulus to create a low-pressure wake region. This pneumatic mechanism reduces base drag and increases muzzle velocity without requiring mechanical moving parts.

Inventive Principle:
Principle #29Pneumatics and hydraulics

3Manufacturing precision

If bullet base geometry is modified to reduce drag, then flight accuracy improves, but structural integrity may be compromised

Engineering Contradiction:
ImproveaccuracyVSAvoidstructural integrity
Core Design Contradiction:
Manufacturing precisionVSStrength

Solution Approach 1:

The drag-reducing cavity features curved ogive-shaped surfaces transitioning from the cylindrical section to the base perimeter. These curved geometries reduce stress concentrations compared to sharp angles while maintaining the aerodynamic drag-reduction function, thereby preserving structural integrity.

Inventive Principle:
Principle #14Spheroidality (Curvature)

Solution Approach 2:

The bullet structure exhibits local quality variations: the front section maintains a traditional ogive shape for penetration, the rear section is cylindrical for stability, and the base incorporates the drag-reducing cavity with specific curvature radii. Each local region is optimized for its specific function while maintaining overall structural strength.

Inventive Principle:
Principle #3Local quality

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

This design improves ballistic performance by reducing drag, increasing muzzle velocity, and enhancing accuracy and precision, while maintaining conventional bullet geometry and structural integrity.

Implementation Method 1

conventional bullets, it is known that they are affected by a pressure difference that occurs on the rearward face. This drop in pressure causes drag

Methodology Applied
Scientific EffectPressure difference: Pressure Gradient

Implementation Method 2

propelled from a gun barrel by expanding gas

Methodology Applied
Scientific EffectExpanding gas propulsion: Pressure Gradient

Implementation Method 3

configured for being triggered upon a blast from the cartridge, in order to reduce a resulting drag of the projectile during flight trajectory

Methodology Applied
Scientific EffectDrag reduction: Drag

Data Source

PatentEP3601939B1Improved bullet
Publication Date: 2024.05.29 NEXT DYNAMICS CORP
  • EP3601939B1 patent drawingFigure 1
  • EP3601939B1 patent drawingFigure 2
  • EP3601939B1 patent drawingFigure 3

AI summary

The present disclosure concerns a bullet (1) configured to be propelled by a blast of a cartridge, the bullet comprising a main body (3) provided with an internal body cavity (7) and having a frontward section and a rearward section provided with an opening in fluid communication with the internal body cavity, the internal body cavity by means of the opening being capable of recovering a portion of gun gas resulting from the blast of the cartridge. The present disclosure further comprises a weapon having such a bullet, and a method for reducing drag from a bullet propelled out of a barrel of a weapon.