FLZ Millita restoration question?

[SpringerGuy]

Guys

I restoring a FLZ Millita air rifle.  Buttstock nut is inside a deep hole and quite rusty.  The hole size measure .920 thousands across.  I am assuming the bolt size is a standard English size 9/16 or 3/4 etc.
Nothing seems to fit any ideas for measuring in deep hole maybe grinding the socket diagram?

Or you know the nut size because you done one before.  Please help. 



Randy 

[oldair]

You might be able to find the nut size using a blob of modeling clay on the end of a stick to make an impression.  I'd expect it to be metric. 
Many years ago I had to grind down the OD of a thin-wall socket, to remove the stock nut from a Japanese millita-style rifle.

Don R.

[45flint]

As Don says probably metric given it was made in Germany.  I’m impressed you are tacking these prewar guns.  The old BSA’s are a nut with a slot, a bit kinder. I had to cobble a tool together to get to them.  Good luck

[KWK]

As Don says probably metric given it was made in Germany.  I’m impressed you are tacking these prewar guns.  The old BSA’s are a nut with a slot, a bit kinder. I had to cobble a tool together to get to them.  Good luck

Old BSA use a large slotted screw. A shorter version of an Enfield stock bolt. A small drag link socket on an extension  works great.

[SpringerGuy]

Thank you, I am going to find out what works.

[Garvin]

If it is a slotted screw like on the BSAs, that would explain why no sockets would fit! I'm guessing you have shined a torch down the hole Randy?

[SpringerGuy]

Danny

It's a Nut - Like me!

An Airgun nut.

[Swissairgun]

Looks like an FLZ Original V with the lever barrel release.

You need a tubular spanner to undo the nut inside the stock, and it will probably be a 17mm nut. Usually they are handmade, so they nuts are not very precise.

Tubular spanners are double ended, with a size difference between the ends, so for example 16mm one end, 17mm the other.

If you cannot find metric, you'll have to pick the closest in imperial.
You could also try your luck using a piece of square section tube, and use a hacksaw or dremel to cut at each corner, then splay out the 4 ends a little. Worked for me once before I bought the tubular spanners.

[KWK]

Looks like an FLZ Original V with the lever barrel release.

You need a tubular spanner to undo the nut inside the stock, and it will probably be a 17mm nut. Usually they are handmade, so they nuts are not very precise.

Tubular spanners are double ended, with a size difference between the ends, so for example 16mm one end, 17mm the other.

If you cannot find metric, you'll have to pick the closest in imperial.
You could also try your luck using a piece of square section tube, and use a hacksaw or dremel to cut at each corner, then splay out the 4 ends a little. Worked for me once before I bought the tubular spanners.

I would get an impression on clay or some duct seal or what auto body guys call dumb dumb. Measure it and go from there. Tubular spanner might or might not reach.
Are they square nuts?
17mm sounds pretty big

[SpringerGuy]

Guys

First off thank you some much for all the help.  SwissAir special thanks I will grind down a 17 mm socket. 

Access hole is .920,  health interruptions forced me to set the project aside for now.  I will post  progress once I can start again.