Lots of posts on HW35's & there T.P size so i thought i would check a few more,most like the older leather piston seal models & for the mostB i tend to agree with them.But there seems to be some models that don't follow the rules.
The Vixen we know is tuned & the port changed to suit so i believe as mine were secondhand so could have been altered any time.Early 70's .22 model 35's are 4mm with leather seal the Vixen in .22 is 3.6 (don't know .177) so in between 1970 & 1979 the port must be smaller.
I checked a couple of my35's with in-between serial numbers & the .22 versions with the Leather were 3mm.The point of this thread is when people say the old leather 35's shoot better which port are they using?
Over the next few months i will have a measure of the older .177's & the new .177 models as well as .22 to see if any thing has changed.I can only go back to 1968 though so if any one can check the very early ones that would be handy.
By the way my 4mm versions have all been Export models weather that makes any difference i don't know as the Export model refers to the style of the Walnut stock.