GTS break barrel

[Shed tuner]

Thanks for the messages. The wee man is #1 in my life right now. Most break barrel work is happening during his naps!

Opened transfer port out to 2.8mm and checked over chrono today.
Exact = 4.91 ft-lb
Express = 4.92 ft-lb
RS = 4.92 ft-lb

I'm liking how equal the different weights are. But it would be nice if the output was a bit higher! More experimenting needed. Either going to open out the port a bit more, or have another look at the piston seal bore and fit. Will sleep on it.

that is not going to be a port problem. A 2.8 mm port will (just) support enough flow for 12 FP.

My guess is your pistons are accelerating way too slowly, so the pressure in turn builds way too slowly, and kills power. You could either lighten them, or get stiffer springs (the total energy when compressed need not be higher, but they need to get up to speed quicker).

Or you have a massive air leak someplace, but I figure you'd have sorted that...