Mk1 Hw77 Value?

[Mateo74]

I have a Mk1 Hw77 that I believe was made in 1984, It is pre Anti Bear trap mechanism. It is in overall nice shape and I would rate it at about 85% condition. The rifle is exceptionally smooth and dead nuts accurate.

This was not made to be a For sale Ad but I simply have no idea what kind of value to put on it?

[Motorhead]

$325 to 400 a loose estimate.  Wood & Bluing etc .... being good to great

[Mateo74]

ok cool I appreciate it.

[grauhanen]

Some shooters may value the 25mm piston rifle a little higher than the 26mm piston that came in later models.  I'm thinking that in '84 the pistons were still the smaller size.

[gard72977]

Looks like I bought this gun!

[Yogi]

Lovely gun.

I'm trying to help a friend who has a very old HW 77.  It is in much worse shape than yours.  .22 shots around 470fps.
However, even with a rear shim, it shoots about a foot low at 20 yards.  Is this normal?  Replacement spring and piston seal recommendations?  Are they hard to work on?  What is "normal" fps output?
Thanks,
-Yogi