This rifle is one I really like. I acquired it in 2019 and was able to cobble together the pieces to make it a functional match rifle.
One thing I did was to add a 1/2" wood spacer and a Freeland rubber buttpad to make the trigger pull length 14 1/4". I finally figured out most rifle butts are too short for me.
I can only date the thing from 1950 to 1960, based on the information here:
The BSA Martini International .22RF Target Rifle The MkII is lighter than the MKIII and the barrel is threaded into the receiver. The MKIII is a much heavier rifle and has a free floating barrel. The barrel on a MKII has the forend screwed on to it, and strangely enough, once you are slinged into the thing, sling tension normal, I don't notice zero changes. I get elevation changes when I move up and down the stock, or the buttplate is moved left or right in the shoulder, but I can't say having the forend attached to the barrel makes any difference at all.
I had to make an ersatz handstop, this is V 1.0 and it works.
I was unable to find a handstop that would work on this rail, no one screws handstops into rails any more, and they stopped doing that in the 1960s
The large screw holds the forend to the barrel.
I shot a few matches with this more modern rear sight,
but I had an original Parker Hale PH25C sight.
I installed the PH 25C when zeroing the rifle for the first time, and thought the sight was defective. I could crank on the knobs and nothing was moving! Or, once the group was centered, the bullets jumped around. It turned out the sight base was loose, and it took squeezing it a tiny, tiny bit to tighten, but the slide is now tight within the base. And, I found out the PH 25C is an 1/8 MOA sight. I am used to quarter MOA sights and it takes a lot of clicking on a 1/8 MOA to move the group. The sight was not broken, it moves repeatably, it was just something I had never encountered.
First match I shot it in, I had a Unertl on top:
and the rifle shot well
it really liked Center-X, which is good ammunition.
I put a Redfield 3200 on top, I prefer these to the dime sized tube on my Unertl
I challenge anyone to shoot tighter groups, prone with a sling, in 90 F weather! Unless you are a zombie, with no heart beat, it is hard to hold steady when it gets hot.