1945 recoilless T22 Sub-caliber?

[94thFS95]

Hello all,
I have a T22 projectile with T126 dummy fuse for the 57mm recoilless, 1945 dated, that I believe was adapted to be a sub-caliber device. The bottom of the projectile has a hole in it (15.35mm) as does the dummy fuse, which is 14.20mm. The fuse also has a set screw in the side much like later sub-caliber devices ive seen. I do have the case, but it does t have anything inside it, and just a threaded hole in the primer location. Can anyone verify this projectile/fuse is a sub caliber? Do you know from the size of the holes WHAT caliber it was adapted to?
-Steve

 

[US-Subs]

It is typical of the subcal for the 57mm. Yours is missing the gun barrel so it is hard to tell what caliber it would have been, most common was .22, but I have seen them in 30-06 as well. Many of the subcaliber rounds for RR were locally made from plans supplied, so there is a lot of variation. Calibers, components, etc. You see most subcals in the 57mm, but 90mm are also found as well as 75mm. I don't think I've seen a 106mm built from a cartridge, but there was the external barrel and specialty ammo.