O-rings must be kept lubricated with silicone oil (never petroleum-based oils, which can cause combustion under high pressure).
The gold standard of the 21st century. These guns feature a high-pressure cylinder filled from an external source (like a scuba tank or compressor). They can fire dozens of high-power shots before needing a refill. Why the Shift to PCP? the modern pneumatic airgun pdf
Whether you are a competitive shooter, a hunter, or a hobbyist, the modern pneumatic airgun offers a level of sophistication that was unthinkable two decades ago. O-rings must be kept lubricated with silicone oil