Looks like the barrel just unscrews. Once you remove the barrel sleeve around the barrel. I would put the barrel in a vice with leather wrapped and spin the receiver slowly. Should not be that hard. If you look at the print it held in with a barrel nut.
I always wrap whatever I'm clamping with thick leather. Been doing this for years works great.
The cutout for the transfer port o-ring is square but the o-ring I pulled out is round. The replacement o-ring I found online somewhere does show a round o-ring so IDK. I can tell my 44's been worked on cuz the seal around the pressure gauge is broken so maybe someone replaced the xfer port seal at some point too and just used what they had. I was able to remove the barrel using a vice. Good news is that it came off without too much trouble. Bad news is that there is no breach seal in the barrel. The breach end of the barrel slides into another housing inside the receiver. I suspect the breach seal is in that housing. I haven't been able to figure out how to access this housing. I also noticed that my transfer port seal is bad. The o-ring is torn. Who knows, I may have caused it when removing the air cylinder.
So, I'm wondering if Weihrauch uses "standard" o-rings or if some of them are custom.
@kendive Where did you get your reseal kit for the 44?
Received my seal kit from ebay, thanks for the link @kendive !! The transfer port has a square-ish cutout for the o-ring. The replacement o-ring in the kit is indeed round but by using the silicon lube that's included in the kit it wasn't too much trouble getting the o-ring to conform to the cutout.
I re-assembled the pistol and did some chrony testing. Per a previous post I misquoted by saying I was getting 720fps with an 8.4gn pellet. It was actually a 7.33gn pellet.
