I was pretty excited about the concept of making a gun, perhaps due to the fact I was never allowed toy guns as a child.
I'd picked up 2 grease gun, and a broken hydraulic gun for a grand total of £3 at a car boot, and after many failed attempts at sticking together different types of metal that were all covered in grease, it finally became the body of the gun.
The nature of the objects gave it quite an industrial feel so with it looking a bit plain I decorated it in a similar fashion with some cogs, tube valves, and wire wrapped up in the aforementioned garden sack. I gave it another handle by sticking on an arm of vintage record player and bunging an air gauge in the end of it, and finished off with the from half of some 1900s field glasses.