I met these guys (gay couple) who host jack off parties at their house from time to time. Usually 4 to 12 guys show up of different orientations (some are married, etc). Yeah good male bonding time and yeah I came and came hard.
I wish there was one around here that I knew about. I've never been, but I want to. It would have to be tres discreet.
I used to go to a group masturbation club a few years ago, we met up every couple of weeks, there was around 7 or 8 guys in the group and it was a great experience. Everyone was free to do whatever they wanted, some guys would be very quiet and sit in a corner, other guys would recommend certain porn scenes to watch
When I was a freshman in college there was an unofficial jack off group. I say group rather than club because it really wasn't advertised. A few guys would get together and jack off while watching X-rated movies or looking at adult magazines or sharing pics of girlfriends, etc. The guys were mostly straight but there were one or two gay/bisexual men there too. Nobody was hit on in case you were wondering. Great way to bond and have some fun.