Hudson steel greasegun, did a vid a while back with the original bolt and springs and using MGC thompson rounds, it worked but not great. The old zinc bolt is pretty strong and was showing no signs of wear but I thought a new steel bolt would be a better idea and new springs, so good old 8ace worked his magic again and also tweaked the magazine catch as it was a bit loose (thanks again 8ace).
With all the work done I thought all would be good but still had problems, so tried old hudson 45 rounds, c-tec rounds (c-tec) were not powerful enough to blow the bolt back) but still getting feeding problems. To be honest I am not sure the mag is the original hudson mag so I played around with it and decided the mag spring was too weak, I had a real mag and with a bit of adjustment to the mag lips it fits fine and feed problems cured (as well as they can be with a modelgun).
So, I now decided to try CAW thompson rounds in it to see if they would perform better and they do they work very well, but after a couple of mags fired problems again, lots of misfires and jams I really could not figure out why. Then after many many weeks of playing around I suddenly realised how dumb I was, I was looking for problems with the gun and not the rounds so looked at the simplest answer the piston seals and low and behold most were in a bad state. So new seals and try again, this time success, it now works probably as best it will.
You can see in the vid that you get some good bursts of fire with the same failure of cap problems or seals not performing and no matter what you get jams with all modelguns, but for a model built in the 60's and lets be honest hudson have never had a good reputation for good firing models, I think with the upgrades it's now firing pretty well for a Hudson.
One other thing and something I never knew until recently the greasegun safety catch. I never knew it actually had one but I saw a review on youtube and the safety is on the top cover (red ringed in the pic) when the cover is open safety off when closed it fits in the finger recess and locks the bolt, simple.
https://youtu.be/k4r6ColpRxQhttps://youtu.be/k4r6ColpRxQ