Quote Originally Posted by look no hands View Post
The hole in the piston rod is normally about the size you say, the buffer washer is normally thicker, so puts pressure on the piston head when the pin is located through the piston rod and piston head, you may need to push the piston head onto the piston rod to get the pin in, obviously the pressure from the buffer washer against the head stops the pin from coming out, although some heads have the pin go through the outside of the head and some locate in the groove the O ring sits in and the O ring also stops the pin from falling out, if I'm honest I'm not completely clued up on the loading taps, I've only ever taken one apart and that was many moons ago, I normally just deal with the Mercury now, like already mentioned, have a look at the nut than holds the threaded cup to the alloy trigger block as they can come loose, if they do then your trigger block will spin and not undo from the cylinder, you will need a thin walled socket (I think its a 17mm?) or box spanner, if you find the trigger block doesn't line up properly with the cocking slot after reassembly then you may need to undo the nut and spin the block a tad to get things realigned and then do the nut back up.
Thanks again, I've been looking at things and I think I have found what keeps the loading mechanism in position. There are a couple of recessed areas machined into the stock and when the action is bolted in they do the job of retaining the loading tap, as you refer to it. I didn't know what it was 'officially' called but tap seems to describe it well. So the stock keeps it in the barrel and the indent ball and spring will positively position it when it is turned to the shooting position. At least that is how it looks to me and I cannot see it being any other way. Most of the Airsporters I have seen in videos appear to have a tap where the lever and cylinder (the part with the pellet hole in it) are one unit and there is a screw and indexing washer on the opposite side of the lever.
On my rifle, which is the S model the lever comes away from the cylinder, The cylinder has an indexing key machined in the lever end and the lever has the corresponding mating key machined into it.

The 3/32" hole in my piston is behind the O-ring groove. If the new pin I have ordered is anywhere near as tight as the original that I removed then there is no way it is going to come out without being attacked with a pin punch and a hammer

Cheers,

Kev