My power down shells turned up today. Managed to break them apart and put the restrictor into the webley shells. Now the webley shoots around 250fps! Perfect for skirmishing and more than enough for cqb.
Unfortunately the green gas reservoir was very lack lustre with an fps of 100 at the most. It could probably go higher but I've found that it leaks quite a lot of gas when you screw it in, much more than the co2 capsules. Practised a few times trying to screw the bolt very quickly but didn't get very good results. Seeing as the power down shell method is working brilliantly I don't really see the point in trying to get the green gas to work.
Need to put a hop unit in and then I should be able to get at least one hit before I reload!
P. S. Anyone want some Dan wesson shells?
EDIT: I'm happy to sell the green gas reservoir if anyone is interested it giving it a go. Â£5 + postage.