I got this neat little TF-41 as a partial trade a couple of years ago, and it has been sitting in the project rack until now.
The TF-41 (or B4-1) is a .177 sidelever, medium-powered rifle in a very rough stock. The action is similar (but not identical) to the QB-88. Like the QB-88, it has short dovetails, and a really short receiver. The gun is bigger than it looks at first; just under 42 inches long with a 14-inch length of pull. The 18-inch barrel is a little much (I'd prefer 10 to 12 inches), but I'm loathe to chop it just yet.
Look at all that lacquer. The finish of the stock is tacky, if not-quite sticky, and I'm itching to sand it off. Doubtful if the wood beneath will be nice enough to take a stain (these cheaper guns usually have a lot of filler putty underneath the lacquer), but it might be a good candidate for painting, or bedliner-ing. Looks like the buttpad could benefit from refitting, at a minimum, or even replacement. This is a cheap-as-free project, so I won't be spending much, in the early stages.
Right away, though, I know I need to change the rear sight configuration. This assembly has nice, positively indexing clicks for fine adjustment, and except for the leaf it is all steel, but the sight leaf is too far back on the receiver and too narrow and shallow for me to get a good sight picture with the hooded front post. It actually is about as far back as I would put a peep sight, so I think that the first fix I'm going to try is just converting this into a do-it-myself peep.
So off it comes. The base of the rear sight is clamped to the dovetails with a single Phillips head screw.
Here's an exploded view, in preparation for cleaning the parts.
At first, it looked like the "hold-down screw" and the elevation adjusting screw might be interchangeable in the base, but they have different threads. Oh well... It would have been nice to have that option, if I found that the sight was way off to the right or left, because reversing the base might have evened out some of the manufacturing misalignments a little. No harm done though.
This is what I plan to use to convert this into a peep sight. It's clearly the ubiquitous, mid-1980's sight that came with Crosman pumpers and CO2 guns. I have a box full of bits like this. I think this one came off of a 2289 Backpacker or a 1300 Medalist... In this closeup, you can really see how narrow and shallow the sighting notch is on the TF-41 sight.
The plastic of the TF-41 factory rear sight is soft enough to self-tap if a pilot hole is drilled. I found out that the notch in the leaf is actually narrower than the hole diameter in the Crosman peep -- 0.051" on the sight blade, 0.060" for the peep hole. So in addition to drilling a hole, I'm going to cut the notch wider, and deep enough to allow me to "bottom-out" the peep blade in its adjustment slot.
This fix is so easy, there is not really anything to show. I used a 1/16" bit in a Craftsman drill to bore the pilot hole, and an X-acto hobby knife to enlarge the sighting notch in the plastic blade. I also cleaned up the factory sight. Here's the finished result:
Putting it back on takes only a few seconds and ... success! That's a much better sight picture! Not bad for an hour of screwing around (mostly camera time). Next, I need to see if I can get it to group, and then I can move on to tuning the action and refinishing the stock.
If you stuck with me this far, thanks for taking a look!
-JC
