. If the benefit of.177 is the flatter trajectory, and the drawback is that the pellet is too light, and the benefit of the .22 is that it hits harder, and the drawback is the ‘loopier’ trajectory, why isn’t .20 more popular? Surely it combines the best of both of the other calibres?
QGURU SAYS: In theory, what you say is absolutely right. In practice, it’s not nearly so clear cut. Let’s begin at the beginning. The largest market for .20 pellets is, and always has been, North America, and pellet manufacturers, not only in North America, but also Europe and
Aother parts of the world, make pellets that they think will sell in the largest market. In North America, there is no limit on airgun muzzle energy, and so there is no incentive to offer a lightweight .20 pellet that, in the UK, would give muzzle velocity halfway between .177 and .22 at energies near our 12 ft.lbs. limit, because people can have any muzzle velocity that’s physically possible, and as a result, .20 pellet weights tend to be closer to .22 weights than .177. In theory, medium weight .177 pellets with around 11.5 ft. lbs. of muzzle energy should give muzzle velocities approaching 800fps, .22 nearer 600fps, so we might reasonably assume that the calibre in the middle, .20, should give around 700fps, with a really useful trajectory mid-way between the other two, but in practice it doesn’t. Let’s take the excellent H& N Field Target Trophy (FTT), rightly one of the most popular pellets in .20. If we take the weight of the .177 of 8.6 grains, divide by the .177 cross-sectional area and multiply by the .20 cross-sectional area to scale the weight up, we end up with 10.6 grains. At 11.5 ft. lbs., the .177 would be doing 789fps, and a 10.6g .20 would be doing 699fps – to all intents and purposes, 700 fps, but the .20 FTT isn’t 10.6 grains; the latest
The selection of pellets in .20 is a fraction of that in the other calibres
The Weihrauch range seem to be the most popular .20 springers in the UK