Joe wrote:
Aidan wrote:

Joe wrote:

Has anyone actually used this for a drive?


No, but I know a man who has.

http://www.pavingexpert.com/stonpv01.htm

Yes, an excellent site, but fairly noncommital on this subject. Only
seems to endorse 100-150mm stone for vehicular use. This seems excessive
to me.

Sandstone is quite weak, compared to concrete (well, some of it.)

I'd only use 20-25mm, if it was bedded in ~100mm of concrete.