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Small calibre projectiles are spin-stabilised to increase ballistic stability, often at high frequencies. Due to hardware limitations, conventional actuators and meth ods are unable to provide satisfactory control at such high frequencies. With the reduced volume for control hardware and increased financial cost, incorporating traditional guid ance methods into small-calibre projectiles is inherently difficult. This work presents a novel method of projectile control which addresses these issues and conducts a systems level analysis of the underlying actuation mechanism. The design is shown to be a viable alternative to traditional control methods, Firstly, a 7 Degree-of-Freedom (DoF) dynamic model is created for dual-spin pro jectiles, including aerodynamic coefficients. The stability of dual-spin projectiles, gov erned by the gyroscopic and dynamic stability factors is given, discussed and unified across available literature. The model is implemented in a Matlab/Simulink simulation environ ment, which is in turn validated against a range of academic literature and experimental test data. The novel design and fundamental operating principle are presented. The actuation mechanism (AM) is then mathematically formulated from both a velocity change (∆V ) and a lateral acceleration (a˜) perspective. A set of axioms are declared and verified using the 7-DoF model, showing that the inherently discrete system behaviour can be controlled continuously via these control variables, ∆V or a˜. Control state switching is simplified to be instantaneous, then expanded to be generically characterised by an arbitrarily complex mathematical function. A detailed investigation, parametric analysis and sensitivity study is undertaken to understand the system behaviour. A Monte Carlo procedure is described, which is used to compare the correction cap abilities of different guidance laws (GLs). A bespoke Zero-Effort-Miss (ZEM) based GLis synthesised from the mathematical formulation of the AM, with innately more know ledge of the system behaviour, which allows superior error correction. This bespoke GL is discussed in detail, a parametric study is undertaken, and both the GL parameters and PID controller gains are optimised using a genetic algorithm. Artificial Intelligence (AI) Reinforcement learning methods are used to emulate a GL, as well as controlling the AM and operating as a GL, simultaneously. The novel GLs are compared against a traditional proportional navigation GL in a nominal system and all GLs were able to control the AMs, reducing the miss distance to a satisfactory margin. The ZEM-based GL provided superior correction to the AI GL, which in turn provided superior correction over proportional navigation. Example CAD models are shown, and the stability analysis is conducted on the geometry. The CAD model is then used in CFD simulations to determine aerodynamic coefficients for use in the 7-DoF dynamic model. The novel control method was able to reduce the 95% dispersion diameter of a traditional ballistic 7.62mm projectile from 70mm to 33mm. Statistical data analysis showed there was no significant correlation or bias present in either the nominal or 7-DoF dispersion patterns. This project is co-sponsored by BAE Systems and ESPRC (ref. 1700064). The con tents of this thesis are covered by patent applications GB2011850.1, GB 2106035.5 and EP 20275128.5. Two papers are currently published (DOI: 10.1016/j.dt.2019.06.003, the second DOI is pending) and one is undergoing peer review.

The history of forensic firearms examination was evaluated to determine how the field has developed during the past 200 years; especially within the past 100 years. As aresult of this evaluation, some related issues were identified for study. The economic and general uses of firearms reference collections were considered as the collections represent potential security considerations within forensic laboratories. A survey was conducted to determine how firearms examiners used their collections, as well as their receptivity to augmenting the collections with modem technology such as photographs and CD-ROM's. A world-wide survey resulted in responses from 110 forensic laboratories. Examiners stated that the collections were used for training, repairing damaged evidence firearms, and demonstration purposes, and whilst they were prepared to accept modem techriology to augment their collection, stated that such augmentation could not replace the actual collection. Research was conducted to partially answer some legal issues, such as Daubert, et al., by test firing bullets from consecutively rifled barrels to obtain best known 'match' and 'non-match' bullets. To date, some 201 examiners from several countries have evaluated the bullet test sets with no errors. Further research was conducted by test firing four cartridges from 617 similar 9mm Glock pistols and microscopically evaluating the fired cartridge casings to determine if they were identifiable to themselves and not the other casings. All of the casings were identifiable to themselves and not to the other 616 casings. Advances in technology have allowed the development of automated ballistics imaging systems. Research, using the previously cited test bullets and cartridge casings, was conducted to evaluate the capability of the various systems, in conjunction with the abilities offirearms examiners. Three different automated systems were used to evaluate the bullets from the l0-barrel test results. One automated system was used to evaluate the 617 cartridge casings, again with excellent results.

The three introductory chapters are intended to summarise the available knowledge prior to the experimental work and to provide useful background information for chemists, with little or no understanding of firearms, who are required to undertake the chemical aspects of firearms casework examination. Chapter 1 provides a much condensed outline of the historical development of firearms and ammunition, with emphasis on ignition systems up to the development of the percussion primer and self contained ammunition. The second chapter presents a comprehensive literature search on the chemical nature of modem ammunition and firearms, with particular attention to priming compositions and projectiles. The final introductory chapter deals with the nature and properties of firearms discharge residues and outlines the most important developments in the search for a satisfactory detection and identification method. The objective of the experimental work is to record experience gained from the 26 year terrorist campaign in Northern Ireland and to use such experience, coupled with further research and development, to substantially improve existing procedures for firearms and explosives residue detection. The experimental work conducted is detailed in Chapter 4. Chapter 5 deals primarily with the Particle Analysis method for the detection and identification of firearms discharge residue, particular attention being directed towards the particle classification system and discharge residue from mercury fulminate and Sintox primed ammunition. Chapter 6 covers suspect handling procedures and contamination avoidance and makes recommendations for permanent improvements in and regular monitoring of the environment in which suspects are sampled. Chapter 7 outlines the development of a method for the detection of the organic constituents of firearms discharge residues, which is compatible with existing inorganic firearms discharge residue and organic explosive residue detection techniques and which enables all suspects to be routinely screened for inorganic and organic firearms discharge residue and organic explosives residue. The final chapter summanses the conclusions, recommendations and comments arising from the work.