I received the rifle today and after putting a few shots over the chrony for a base line started the disassembly . I was quite surprised when I measured the barrel with an AOL of just 17.5” . I will be replacing the barrel with a .222/ .223 liner that Brownells sells in 26” length. First on the agenda is to replace the heavy bottle with a .5L Acecare carbon fibre bottle . The rifle was sold with an Altaros regulator that screws on between the drop block and bottle , the plenum size is unknown but I hope to have that measured up using a liquid . Next up , air flow . I measured the porting and there are quite a few restrictions . First is the path between the plenum and the valve inlet , there was a centre hole at .121” and four other holes staggered around it ( didn’t measure them ) . I opened that up to .275” and blended the entrance into the drop block . The valve stem itself is .155” and the port is .305” which isn’t horrible but I’ll be replacing it with a peek poppet and a thinned our stem . Next is the valve outlet, which is similar to the Hatsan valve with multiple holes around the circumference . This works but is not my preferred method for managing air flow . I’ll be doing the Bob Sterne trick and use setscrews and open up the hole that lines up best with the transfer port through the action . Next is the transfer port through the action , it measures at only .173 “ and that will not work for making the power I’m looking for . This is going to be tricky to open up as the transfer port gets drilled out using one of the barrel securing setscrew holes . I’ll have to think about how to get it to at minimum .223”. Last is the barrel . I haven’t thought that part out yet , all I know is it is 5/16” OD and the action is 12mm . I’ll most likely use a thimble similar to the FX Crown continuum barrel set up .