So, I pulled out my CAMT handed to me by an old SNR NCO when I was in mortar PL back in about '76. The spec for zeroing Sten is... "25 yds, 5 shots fired, group should be 2" above POA." There's more about PV but who cares? It further states that... "A trained man should be able to group all five shots into a circle of 3-1/2" radius."

We shot SMG C1 at 100 yd but it's an SMG, not really meant for distance. Group size would be x4 for 100M...