Socket Cap Bolts.

Very hard to find thread pitch M6x0.75

This is the bolt size that Anschutz use to bed their rifle actions into their stocks. These bolts are £10 each from Anschutz.

These bolts are A2-70 Stainless Steel, a quick description of this copied below which I found on the net...

"Thus the designation A2-70 denotes a bolt having the same corrosion
resistance as 1.4301 (304) stainless steel and an ultimate tensile strength of 700N/mm2."

Seem like pretty strong bolts then!

They are 45mm long from the lower part of the head and can of course be easily cut down to size, the actual thread part measures 25mm, so in reality you could cut them down as far as 20mm, and still have a good 5mm of thread in use.

I had terrible trouble finding these and had to go overseas, so am now offering the surplus here.