I have a recollection of seeing a .22 L1A1 SLR but I'm not sure when on where.
I think it may have been at the end of one of our CCF field days when the RAF Section returned to school after running around the woods doing escape and evasion exercises all day. The Army had sent the infantry to school to do training with the Army cadets and when we got back there were very large bangs coming from our 22 rifle range. On investigation we found the Army using 80mm Carl Gustave anti tank rocket launchers in there ……. with the sub caliber training device fitted of course. Used a 7.62 size round with a rounded hollow copper cap, which produced a very big bang similar I was told, to the effect of the real thing. I was very lucky and despite my blue uniform they let me have a go
I still have the plywood tank target that I even manged to hit, one of my treasured possessions!
I think the .22 L1A1 was there as well, I remember being told that it had a specially lightened breech block for the automatic reload to work with the .22 ammo, but that they still got a lot of stoppages with it.