I'v eheard a few different sides to the HW choked barrel or not and so did some measuring, I have had a .22 hw95 which was deffinately choked as when i cut the barrel weight off to fit a 1/2" unf the diamater of the barrel end opened up .3 of a mm. I've had a hw80 which was not choked (tested in the same manner via cutting of the barrel and i have a 97 which is not choked.
But i also have a HW35 in which both barrels have a slight choke. which i tested by making up some brass rods of exactly 4.49mm and 5.49mm, these slip into the breech end easily and are to tight to fit the muzzle end.
Maybe not the most scientific way of measuring them but it got the answers i wanted.
The 95 i chopped (as mentioned above) was useless afterwards and the accuracy was US. 20mm groups at 25yds. before it was 15mm at 35yds You live...... you learn
ps, nice loft find there bud! the 85's stock was a lovely shape with a proper montecarlo cheekpiece and the grip cap as in a 35E and 77.
PAUL