FSB installation help

[staylo]

Installing an F marked A2-style FSB on new barrel, and committed the cardinal sin - over reamed the forward taper pin hole. Rear hole is perfect. Any hope to salvage somehow?

[SteveWag]

Is the diameter of your reamed hole tapered? If so do you mean the tapered pin does not get tight and the big end of the pin falls below the outside of the sight? If so, just get the next larger pin. they are sold by numbers from very small diameters to over 1-inch at the small end, each number overlapping the lesser number. Can you measure the small end diameter ? If so let me know and I will check my inventory. The other thing you could do is to tap the sight base, both sides with #6 or 8 and install short set screws.
Steve Wagner

[staylo]

Is the diameter of your reamed hole tapered? If so do you mean the tapered pin does not get tight and the big end of the pin falls below the outside of the sight?
Steve Wagner

Yes, that*s exactly what happened. I reamed with a #2/0 reamer and took it too far. Now I can press the taper pin flush with the FSB with my finger. If I tap it tight it is below the surface of the FSB. Unfortunately I*m not sure I have anything accurate enough to try to measure the pin. It*s a Colt taper pin.

[Bang]

LocTite.

[staylo]

If so, just get the next larger pin.
Steve Wagner

If I*m understanding the sizing of these pins correctly, it looks like I need a #0 x 1* pin and I*ll need to grind the length down to fit?

[JoshIronshaft]

Order the same taper pin from mcmaster cart, but longer, and cut/grind to fit

[staylo]

So just for future reference, for anyone else who might have made the same mistake I did and stumbled on this thread looking for a fix, initially I just ordered a size #0 pin(the next size larger) that was 1 inch long, but I would’ve also needed to order a size #0 reamer and then ream the hole a lot larger than standard to fit the #0 pin. Instead, I bought a #0 pin that was 2 inches long. On taper pins the large diameter sets the pin size, and the longer they are the smaller the small end gets, so the small diameter end of the 2” taper pin was essentially the same size as a standard #2/0 FSB pin that continued to get larger until it reached the #0 pin size at the big end. That allowed me to cut a slightly oversized standard taper pin out of the 2” #0 pin. I had to grind a little off the small end of the pin to get the proper length, and I had to cut the pin on the big end to the proper length, but I ended up with exactly the custom pin I needed, and didn’t have to touch the hole on the FSB. If you overream your FSB taper pin hole, just buy a #0 sized taper pin that is 2 inches long, and custom fit it to the overreamed hole.

[Xringshooter]

YOU DUN GOOD! Thought it through and came to a good easy workable solution. Most people jump the gun and don't stop, sit back, relax and think and then make things worse.

[Bang]

Great post!

[Gerrty]

These are my favorite kinds of issues. It looked like a big mess at first, but working thru it intelligently like you did I bet taught you a bunch of new techniques. You also learned about hardware, reamers etc. all into the learning bank. Imagine if the pin just went in the first time and that was it?.... no new things learned! So,...make sure you mess up the next job too! of course in the name of higher learning. Have fun,

Gerry