Adaptive Muzzle Brakes AMBs Managing and Mitigating Firearm

Adaptive Muzzle Brakes (AMB’s) Managing and Mitigating Firearm Recoil Through the Development of Novel New Designs of Muzzle Brake

Introduction • Project completed as 3 rd year dissertation. • Proof of concept study using CFD of a novel new muzzle brake design. • Contents: 1. 2. 3. Background information and reasoning My research so far What next?

Body Armour Development [1] [2] 1980’s 2000’s

Methods for Defeating Armour • Increased projectile mass or speed o o Both are increasing projectile energy. Both will result in increased recoil. • Projectile shaping and material o o Highly effective and can be applied to existing calibres. Expensive to produce.

Firearm Development • Bullet calibres in small arms have remained the same for nearly half a century and muzzle velocities have only slightly increased. o Therefore projectile energies in small arms have remained roughly constant. • Due to the improvements in body armour there are indications larger calibre rounds may be required in the future.

The Problems of Recoil • 20 J of free recoil energy is commonly cited as the point where recoil becomes uncomfortable for the user. • A study carried out by US Army Research Institute of Environmental Medicine in 2004 showed that: o 93% of soldiers experienced bruising to the shoulder after firing only 15 rounds with a high recoil rifle. o Soldiers firing weapons with high recoil would quickly develop a “reluctance to fire”.

Recoil Mitigation Two Methods of Mitigating Recoil: 1) Mechanical Systems: o Floating Barrel (as found in the H&K G 11 Advanced Rifle Prototype) [3] [4]

Recoil Mitigation 1) Mechanical Systems: o Springs and Dampers mounted in the Rifle Stock [5]

Recoil Mitigation 2) Aerodynamic Systems: o Muzzle Brakes [6] [7]

Muzzle Brake Geometry Current Historic [8] [9] [10] [11]

Muzzle Brake Geometry Current Historic [12] [13] • Muzzle brake designs have remained strikingly similar to the designs used in World War 2.

The Muzzle Brake Trade-off

Adaptive Muzzle Brakes (AMB’s) Pre-firing Post-firing • Adaptive muzzle brakes are muzzle brakes that feature geometry capable of moving in response to firing. • AMB’s could potentially solve the problem of the muzzle brake trade off. • They could also allow for dramatic increases in efficiencies over current muzzle brake designs.

Muzzle Brake Designs Tested Perforated Circular Shock Reflection High Angle Arrowhead Static AMB Geometry

CFD Results – No Muzzle Brake • Velocity contours over a period of 4 millionths of a second. • Contours range from 0 to 1400 ms-1.

CFD Results – No Muzzle Brake • Total pressure contours over a period of 10 millionths of a second. • Contours range from 0 to 50 atmospheres of pressure. [14]

CFD Results – AMB Closed • Total pressure contours. • Contours range from 0 to 50 atmospheres of pressure.

CFD Results – AMB Open • Total pressure contours. • Contours range from 0 to 50 atmospheres of pressure.

Summary • This research has shown that: o AMB’s can significantly reduce the recoil of a firearm. o AMB’s do not increase the sound pressure levels for the user upon firing. • Due to this AMB’s eliminate the problems traditional muzzle brakes face. • The use of AMB’s could allow for a dramatic increase in the lethality of small arms through the use of higher energy rounds with no detrimental effects on the user. • AMB’s could also be applied to large calibre weapons and moving platforms such as: o o Tanks Aircraft Naval Guns Artillery

What Next? • Looking to continue the development of AMB’s into my 4 th year group design project. • Pitched this idea to weapons division who have provisionally agreed to fund my research. • The final aims of the project would be to produce a far more refined AMB design that will pioneer: 1. 2. Utilising axially moving components to allow for dramatically increased durability. A mechanism that will seal the hole the projectile passes through after it has left the muzzle brake which could allow muzzle brake efficiencies of 7080% to be achieved (as opposed to the 30 -40% efficiencies of current designs).

Any Questions?

Bibliography [1] : PASGT Vest Image, Flatwood Museum, http: //www. flatwoodsmuseum. com/uploads/2/3/4/8/23482946/422880_orig. jpg [2]: IBA body armour, wikimedia, https: //upload. wikimedia. org/wikipedia/commons/5/54/Multi. Cam_IBA. jpg [3]: H&K G 11 Cutaway, http: //weapon-planet. ru/images/gallery/HK_G 11_01. jpg [4]: H&K G 11 Barrel Assembly, http: //www. fadych. com/wp-content/uploads/2015/03/media 4051. jpg [5]: Recoil Mitigating Stock, https: //www. gunsamerica. com/User. Images/1881/930353445/wm_3311197. jpg [6]: Muzzle brake High Speed Photography: http: //kuulapaa. com/onewebstatic/4 d 0 e 0 dc 4 b 7 -Comptest-Ferfrans. CQBSivu. A 4_2_FIN_Single_1500. jpg [7]: Marines in Fallujah, https: //upload. wikimedia. org/wikipedia/commons/f/f 7/4 -14_Marines_in_Fallujah. jpg [8]: M 1 A Rifle Muzzle Brake, Police Mag, http: //www. policemag. com/channel/weapons/articles/2002/01/arsenal. aspx [9] : . 25 cal. Muzzle Brake, Amazon, http: //www. amazon. com/17 -HMR-Cal-Muzzle-Brake/dp/B 00 GRDE 03 M [10]: Boys Anti-Tank Rifle Muzzle Brake, Rifleman, http: //www. rifleman. org. uk/Enfield_Boys_Anti-Tank_Rifle. htm [11]: Grizzly Gunworks Muzzle Brake, http: //www. thetruthaboutguns. com/2014/04/joe-grine/gear-review-grizzly-gunworks-ltd-muzzlebrakes/ [12] : Panther Tank Muzzle Brake, http: //www. network 54. com/Forum/47207/thread/1195602367/Panther+muzzle+detail [13]: 30 mm Mauser Cannon Muzzle Brake, https: //en. wikipedia. org/wiki/Muzzle_brake [14]: . 308 Rifle High Speed Photography, http: //kuulapaa. com/home/highspeedx. html