BSA rear guard screw size? Superstar, Meteor etc

[evert]

M5 in my Supersports and Superstar. Thats the rear trigger guard screw, the fronts are M4.

[Phil Russell]

This is getting more puzzling. Thank you evert. I tried M% but it was too big ... pity as I have a lot of them.

I am wondering if the best solution is to strip the action and re-tap the thread.... and put a nice screw in place.
Cheers, Phil

At the same time ... if someone has an electronic version of the Owner's Manual, I would be very pleased to have a copy.
Cheers again.

[evert]

This is getting more puzzling. Thank you evert. I tried M% but it was too big ... pity as I have a lot of them.

I am wondering if the best solution is to strip the action and re-tap the thread.... and put a nice screw in place.
Cheers, Phil

So, after making this duboius assumption based on memory and a bunch of mixed up supersport parts, I realized that my contribution would just add more confusion. So I went and actually measured some screws on some guns:

Late Supersport (presumably Birmingham made):
Rear: M5X0,8
Front: M4x0,7

Early Mk2 Supersport and Superstar:
Rear: measures in at about 4,6mm, and the thread pitch is VERY close to 0,7, and does not match up with any of my TPI gauges.
Front: M4x0,7

I measured a mk3 Meteor too:
Rear: the same as the early Supersport and Superstar
Front: not measured today, but earlier confirmed to be a 2BA (I actually made some screws that I threaded with a 2BA die for a meteor a while back.)

[piggy589]

I must admit I've not had to source screws for later guns,up to mk6 meteor, 2 and 4ba used.

[Thegreg]

I can confirm that my Superstar, Supersport, Goldstar and even mk1 Lightning all have a 2BA x 1.5” rear guard screw. Front stock screws are all M4. It’s not uncommon to see different fasteners mixed and matched, Webley did exactly the same.

Cheers
Greg

[Phil Russell]

Well, thank you all for taking such trouble. I appreciate it. I wonder which thread the Knibbs part is.
I am warming to the idea of retapping the thread now....
Cheers, Phil

[evert]

Well, thank you all for taking such trouble. I appreciate it. I wonder which thread the Knibbs part is.
I am warming to the idea of retapping the thread now....
Cheers, Phil

Or you could get a more recent supersport/lightning rear block, that is threaded M5. Then you can change back if you want to get the gun original again.