This is a high capacity modification of the washbear pm552. In alpha testing ( not finished yet).
I'm hoping someone who is smarter than me and knows how to CAD design can edit the model to swap cylinders (barrels) fast and improve the automatic mechanism because this model has never been printed or tested.
This file includes a fully printed 22lr cylinder and a 22lr cylinder that has inserts for "stainless steel capillary tube 6mmx8mm" which is a widely available tube to buy online.