There is no problem with the cleaning pellets per-se, the problem is most beginners don't understand how to use them. I have seen the blank stares on people's faces on what to do with them. Some people don't even realize that they are meant to be shot. Seems obvious to some who have been at this forever but not new airgunners. Here goes a mini-lesson. First off, you need the right size for the caliber you are cleaning, I know it sounds obvious but believe me it needs to be said. Second, you are going to need some kind of pellet seater to get them into your bore. Yes, you do use more than one. More on that later. Third, you are going to want a cardboard box to shoot them at. More on that later too. Cleaning pellets use to be very popular when springers were all the rage and they were meant to be used in multiple. Depending on the power of your gun you would use three to five cleaning pellets stacked in the bore so that your piston wouldn't slam and ruin your piston seal. You would determine how many to use by starting high (5) and if the pellets don't make it out, push them out with a rod and try (4), etc. You want them to shoot out reliably but not easily, to protect from slamming the piston. It was my understanding at the time that the pressure pushing on the pellets gave a really good even pressure on the bore and of course did no damage. A common practice was to put some cleaner, that Beeman use to sell, on the middle pellets, as you were stuffing them in. You would then shoot the pellets at a cardboard box a couple of feet away. The pellets would easily go through the side of the box but be trapped inside where you can open the top and check out the pellets to see how clean your bore was getting. Pcp's today don't need cleaning very often, or at all in some cases, but springer bores get seasoned quite a bit more because of chamber oil used for the seal and the flash of high heat of compression. Whatever, they do get dirtier. Since a PCP has no moving parts you could shoot one pellet (again, with sound suppression removed) but it wouldn't have the same outward pressure from shooting multiple pellets and wouldn't work as well. Once you're happy with how the pellets are looking put some ballistol or silicone on a set of pellets and follow with a dry set, done. Beeman use to sell a thing called a pellet seat that was very handy at stuffing the pellets in, I still have mine but don't know if they are even made anymore. Again, cleaning pellets are truly not worth the trouble, get a patchwork kit. JMHO