Here's my latest doodling in Solidworks. I'm trying to create a more compact and portable version of the Caliburn.
The design uses a 1.5" id plunger tube as opposed to a 1 3/8th" that has become the norm. The draw length is only 5 inches, but it has been shown that the traditional 6+ inch draw of a "full [k26]" is pretty inefficient and most of the energy in a full [k26] setup is wasted.
Friction concerns is the main issue with running a 1.5" plunger tube, but I have plans for a floating O-ring seal that should address this issue.
Overall length with the stock collapsed is 28.5" at the moment, 4.5" shorter than the Caliburn. And if my calculations are correct, it should have the same if not better performance than the Caliburn.
Edited by stuck by stefan, 13 March 2018 - 11:44 PM.