Pistons and sears

by Tom Gaylord
Writing as B.B. Pelletier

This report covers:

  • Two basic types of pistons
  • Center-latched pistons
  • Side-latched piston
  • See the difference?
  • Gas springs

I’m going to look at how triggers interact with pistons in spring guns today. I thought some of the blog readers may not be aware of some of the subtleties of sears and triggers as they relate to pistons.

Two basic types of pistons

Spring pistons are latched or “caught” by their sears in 2 different ways. These 2 ways are so vastly different that they dictate what types of triggers will work with what types of pistons. Until you understand the differences, you can’t appreciate why certain triggers such as the Rekord won’t work with certain types of pistons.

Center-latched pistons

A center-latched piston has a rod in its center that in some way gets latched or “caught” by the sear. When it’s latched, the sear restrains the full force of the mainspring. That can be well over 100 lbs. of force in the case of a coiled steel spring, or several hundred psi of gas pressure in the 2-piece expanding cylinder of a gas spring. The sear prevents the piston from moving until it’s released by the action of the trigger. read more


B.B. looks at gas springs

by Tom Gaylord, a.k.a. B.B. Pelletier

This report covers:

• What to call them
• Can gas be a spring?
• Confusion reigned supreme
• We bought one
• Meet Ben Taylor
• It worked!
• Ft. Worth airgun show

What to call them
Today, I want to tell you about the saga I had when I got into gas-spring airguns. Let’s start with the name. Some folks call them gas struts, while others call them gas rams. Some, like Crosman and Gamo, use trademarked names like Nitro Piston and Inert Gas Technology to name their gas springs. But the industry that makes the units calls them gas springs.

They’re called struts when used in assemblies, like the MacPherson strut in a car’s suspension or the suspension strut on an airplane’s landing gear. I don’t know where the term “ram” comes from, but I’m sure there’s a reason people use it. read more