Adapting spare parts tip

[Benelli B76]

Had an idea today, but someone may have done this before. Just re-blued an old BSA but lost a locking screw. After hunting around found a replacement (think it could be 7BA), but the head diameter was 1mm too small 3.8 instead of 4.8mm and the head was also far too thick. Thought what shall I do, I know, squash it flat.Drilled a 2.5mm hole in a piece of flat bar so thread is protected, put it in a vice and squashed the head to 4.8mm diam and it also ended up the right thickness. Some of you experts may have noticed the screw was missing on my earlier thread.

Baz



missing-

[Binners]

You clever old FFFFellow

[Benelli B76]

You clever old FFFFellow

Seemed simple but I never thought of it before. Its easy to turn down a screw head thats too big but how do you make the diameter bigger when its too small. At 3.8mm it did not lock the cocking lever pivot screw in place, it could unscrew. Was the only 7BA screw I could find.

Baz

[AC99]

Well done - a stroke of genius! BSA seemed to use a variety of thread forms on their old air rifles.
My collection of BA screws would not have stretched to 7BA. After retiring from industry many years ago I now only have a small collection of even ones, 0-8BA.
It is amazing how you can improvise when the need arises especially when replacing those elusive lost screws.

[Benelli B76]

Well done - a stroke of genius! BSA seemed to use a variety of thread forms on their old air rifles.
My collection of BA screws would not have stretched to 7BA. After retiring from industry many years ago I now only have a small collection of even ones, 0-8BA.
It is amazing how you can improvise when the need arises especially when replacing those elusive lost screws.

Just guessing it is 7BA by diameter, but have no die to check it, and I think BSF never went down this small ? BSA must have used some BSF threads on these rifles as I think BA only went up to 6mm ?

Baz

[fatttmannn]

Seemed simple but I never thought of it before. Its easy to turn down a screw head thats too big but how do you make the diameter bigger when its too small. At 3.8mm it did not lock the cocking lever pivot screw in place, it could unscrew. Was the only 7BA screw I could find.

Baz

a flash of insperation there Sir.