Workshop Project to Production Floor

Workshop Project to Production Floor

by Tim Smith

I recently had the opportunity to visit with Lloyd Sikes. For those of you who do not know of Lloyd, he is an engineer for marine navigational equipment. In his off hours he was looking for a way to get consistent velocity out of big bore airguns. He was working on several ideas and thought of an electronic system that could measure the air pressure left in the tube and adjust the amount of air needed to propel the pellet after each shot. As the pressure drops the valve is left open a little long to obtain the consistent velocity. A side benefit was the ability to adjust the power level to get a few high power shots or several low power shots.

During the visit, I had the chance to see the evolution his valve design. Lloyd’s first prototype was mechanical to test his theory. While this simple device may look unimpressive, it was just the beginning of things to come.

An early mechanical valve prototype.

When the mechanical prototype was successful, Lloyd set his sights on an electronic version. After building the electronic unit, Lloyd programmed the unit in BASIC programming language and would download his program using a RS232 cable.

An early electronic valve prototype.

There were several obstacles to overcome while designing a system that monitored the air pressure in the tube. One was how to run a sensor wire from a sealed air tube to the electronics without causing an air leak. Over time, he designed a leak proof system.

To test his electronic valve system Lloyd built a beautiful .458 caliber airgun. The beauty of it, is the wires, gauges, display, and circuit board are all visible. The .458 is a single shot airgun and the loading mechanism is so easy and smooth that I hope it will be on other airguns in the future.

During our visit, Lloyd asked me if I’d like to fire his .458 prototype. And of course I said “Yes!”. It’s a big airgun, but very comfortable to hold, however. We set it on a workbench for my shot. Lloyd set a pressure treated 4×4 on the other side of his shop just in front of the backstop he uses for testing. After putting on some ear protection and loading the 405 grain bullet I was ready to fire. After pulling the trigger there was some noticeable recoil for an airgun. After removing our ear protection, the first words that Lloyd said was that I just fired a 500 foot pound airgun. That was impressive to hear. Equally impressive was the 4×4 that I shot at. It had a big entrance hole where the pellet hit and an even larger hole where it exited and kept on going.

Benjamin Rogue (Top). Lloyd’s prototype electronically controlled big bore airgun (Bottom).

What makes Lloyd’s valve design unique is that it uses an air spring instead of a conventional metal spring. The air spring is more efficient because there is no hammer, and therefore no bounce.
As you may have guessed, Lloyd’s design is what Crosman uses in the Benjamin Rogue. The ball really got rolling when Lloyd met Tom Gaylord at an airgun show. Tom was the man who orchestrated a meeting with Crosman. In Lloyd’s words “He saw the potential more than I did. Without Tom, this would still be in my workshop.

Airgun Hobbyist Magazine