new idea for bolt action sniper rifle in Sniper Rifles Posted March 22, 2011 · Report reply pneumatic pump airguns work that way. You pump the gun one to ten times before firing. It's a decent solution, especially as for airsoft, it probably wouldn't take more than one pump. I don't imagine cost would be much of an issue as Daisy sells similar guns for ~$50, and they shoot lead pellets at 800+ fps. The only "cost" issue would be swapping for a 6mm barrel.