Blog 6th Aug 2018 – Precision Grouping As a younger man, my dad enjoyed around 2 years of training as a “sharp shooter” in the army – which in modern parlance might be described as sniper training. I have no recollection of what rifles he used, nor of the specifics of his training – but I know he was good. I do have a vivid memory of the two of us visiting air shooting galleries at funfairs when I was a kid and him teaching me how to improve my chance of winning the fluffy toy. A few years after the loss of my dad, I got a strong urge to explore sports air shooting a little further. I found a suitable club and after a few phone calls and following a safety induction course, became a probationary member. While on probation, experienced members vet you while you shoot on the range, assessing both your safe handling skills and the way you behave. That's the time you can make genuine mistakes but where other more experienced people can step in both to correct and educate. I count myself very lucky because the club turned out to be really exceptional, catering for all the important air shooting disciplines and attracting a friendly group of people from very different walks of life. Originally, my intention was to train myself within a supervised club environment over the course of a year to learn to properly and instinctively handle air guns safely. After that, I planned to swap to clay shooting with shot guns. But as sometimes happens with long term plans, I found the discipline and engineering involved so interesting and challenging that 5 years later on I still haven’t moved on. UK legal limits for the muzzle energy of air guns is cut and dry - for a small air pistol the limit is 6 foot/lbs and for a longer air rifle, 12 foot/lbs. The foot/pound measurement captures both the speed at which the projectile flies as well as its weight (often measured in grams or more commonly grains). In order to keep within UK legal limits, a typical .22 pellet (15.89 grains) must travel at less than 583.1 feet per second (FPS) when shot from a long rifle, while a lighter .177 pellet (8.44 grains) can fly at 800.1 FPS. So what does that actually mean... well, by any standard UK air rifles are really very low power devices. You could easily throw a brick with more energy, while a crossbow will deliver 10 to 20 times the amount of energy. But, any tool, regardless of it being a car or a kitchen knife can cause irreparable harm if handled irresponsibly. Air guns are no different in that regard. For the responsible air rifle user, tools capable of accurately measuring muzzle speed are always in the back pack. For an engineer, tools capable of measuring energy over time, help identify 'drift' (which will directly impact accuracy). The same engineer might observe changes in performance linked to changes in temperature, or might find the point at which air pressure in the rifle reservoir tapers off but which results in a muzzle energy peak. Other tools might provide a way of judging how well pellets group at a target by accurately detecting points of impact without having to use card sheets – and off course there are other interesting possibilities. With roughly 5 years shooting experience under my belt, the potential for electronics to provide useful tools has been clear from day one and so an old friend and I have been hashing out some ideas on paper as to what sort of useful tools we might build. Early days yet, but keep an eye on my web site www.PrecisionGrouping.com for more details. Comment | Back to Quick Links...