Get mick Trowmans to make you a titanium one with a quick fill chum .
You can tell him what size you want .
And the quick fill option prevents all those nasty particles of brass from shaving off (through repeated screw on / screw off action ) and getting inside your reg .
At least that what can happen on the walthers.
Do the sums mate .
Just a quick fill conversion will take you a good chunk if the way to a complete lovely new cylinder .
No I'm not connected to mick in any way . He's a top bloke tho