The 65 was first introduced in 1965. A revised version appeared about 1978, simultaneously with the then-new FWB model 80 match pistol. To some extent, the changes were to allow commonality of parts between the two models. Beeman called the revised gun the "Mark 1," or "Mark 2" for the short-barrelled version. Note, the "Mark" numbers were strictly Beeman marketing inventions--and confusingly, both apply to the LATER version of the gun. FWB literature makes no distinction for the revised frame, and notes the short-barrel model as "K" ("kurz") or "Junior."
This pair of guns illustrates some of the (all relatively minor) changes and optional features of the FWB 65's production run. The two are a long-barrelled, first version gun serial 65360; and a short-barreled, second version "Mark 2," serial 130449.
The older gun has a factory barrel sleeve, which adds weight and a nicely proportioned, tapered appearance. The sleeve is seldom seen on US imports, for some reason, though Beeman offered a clamp-on detachable barrel weight for each barrel length. The newer shorty gun is without a sleeve.
Note that the older gun has an adjustable walnut match grip, which were made in both left and right-hand versions, and in several sizes. The newer gun has a stippled walnut sporter grip; these were checkered instead of stippled on the earliest examples, and likewise offered in different sizes. The base grip in Europe was actually just simple molded black plastic, but most buyers seem to have upgraded as these are seldom seen.
The most noticeable difference between the two versions is the length of the grip tang--longer on the newer version, left in the photo.
The sights are also different, the later versions being shared with the model 80. The newer rear sight is much wider (better for formal paper-punching as an anti-cant reference), but I prefer the smaller early rear sight for all-round shooting (less likely to get snagged or damaged). On both sights, the sight notch width is varied by rotating the cammed rod in front of the blade; the earliest 65's had a simpler sight with interchangeable blades to get different notch widths.
The early front sight housing is rounded, and as you can see nicely mates with the weight sleeve diameter. The later model 80 one is much more angular, but uses the same interchangeable sight blades. The difference in barrel length--only about an inch and a half--makes a surprisingly large alteration in the pistol's balance and overall feel.
The 65 was originally designed to be used as either a recoilless match pistol, or a recoiling firearm trainer. To eliminate the recoilless feature, a simple piece of metal is screwed to the front of the upper receiver and overlaps the lower frame (both of mine are missing this bit unfortunately!). Along with this, the trigger mechanism can instantly be switched to the much heavier "firearm" mode by flipping the tumbler switch in front of the trigger, with no need to change other adjustments. The recoiling mode, interestingly, also requires taller sight blades.
Something to watch for in these guns is the age of the seals. The white breech seal in the older gun is due for replacement, while the blue one in the newer gun is the result of a recent rebuild. The little white pad below the breech seal is the snubber that pushes the trigger-block out of engagement when the breech is closed. The most critical replaceable part in all the FWB springer pistols, though, is the resilient bumper on the front of the piston. Generally all FWB springers are incredibly durabe, but when you see little white chunks in the barrel it's definitely time to stop shooting and go for a rebuild.
OK this is silly...but has any airgun ever looked cooler with its action open, than the 65? The cocking stroke is about 120 degrees and quite easy to manage, though some older shooters find it tough on wrists and elbows. I have found a good work-around is to hold the gun in my right hand with the palm facing up instead of sideways; then pull straight back on the cocking lever with an underhand grip.
For what it's worth, the most common variant of the 65 seen for sale here in the US has the late long-tang action, long barrel without sleeve, and match grips. What I see for sale on German sites tends toward the older short-tang action, with long sleeved barrel and sport grips. Neither of my guns is thus quite typical; the short barrel in particular is a bit rare.
Well here's one last look, the older gun in the first photo and the newer shorty below. The latter, upon which Dave Slade has performed his magic, is definitely one of my "babies"--absolutely the last air pistol I'd ever part with.