LOL Bob, i want an 80fpe gun that can do 2.0fpe/ci, i am sure the airforce guns with Co2 adapter can hit that magic number but its not usable. Rkr, i was shooting 55 grains in huben 25 cal around 845fps. but that pellet can only group at 25 yards, it was spiraling and printed 3 feet at 100 yards. LOL
I have a few ideas to improve flow. The oblong transfer port is not as good as a round hole for flow. Shifting the shape from round to oval then back to round can’t be good . Also the oblong is inline with the stem and probe lengthwise. I think a .025 wire positioned flush in the center of barrel transfer air hole to support the pellet as it is chambered would be better. A bore size round transfer hole could be used then. How to machine provisions to add this ? Shouldn’t be too hard. Has it been tried already?Edit: wouldn’t be a wire exactly but a thin insert installed from underneath.
Well I used four ports on the Lucky Shot 223. Worked very well. Marko
My idea would be more geared towards pellets than bullets. I made an example sketch. The example dimensions would fit a .250 wall barrel. A razor blade could be adapted for maximum effect. On some applications I think it could be used.
You do realize that at the instant the pellet starts to move, the column of air behind it has little velocity, beyond just filling the chamber and ports with air to the pressure of the reservoir, right?.... In fact, just as the valve opens, what is happening is that the random vibrations of the air molecules just becomes organized in the direction of the pellet, as it increases the pressure in the ports and chamber behind it.... Once the pellet is halfway down the barrel, and travelling perhaps 800 fps, then the airflow velocity is a similar value, and you can use CFD to model the flow.... but I don't see how you can do that before the pellet moves.... Perhaps I just don't have a good enough understanding of CFD....Regardless of the details of CFD modelling, I look forward to your results when you get a working prototype of your "axial flow" design....Bob