The gr25, just treat it like a regular aeg m4. Keep the oem hopup & nozzle and tinker away on everything else. Don’t bother with some absurdly long inner barrel. 400mm’ish tops imho...
I have one I’ve been working on (not touched it in months though) that will be powered by a wolverine reaper, powered by propane if I get it working right lol
I have one I’ve been working on (not touched it in months though) that will be powered by a wolverine reaper, powered by propane if I get it working right lol