Hi RWF:
Good grief man! I read with interest your posts concerning shotguns on another site. We get around.
I have a SG m70 Winchester .220 Swift. Mine was mfg. 1936 despite it not being released until 1937. My gun has a serial number of 4XXX.
I thought that the M54 was not chambered in Swift! I thought that the M70 and the Swift all were announced in 1937 as the new hot item!
At a weak moment, I re barreled and restocked my Swift to make it an ultimate varmint rig.
When the gun was a stock hunting gun, I took many deer and varmints with it. All deer were killed with on shot.
I will not brag about the long shots and great kills that I made with the Swift, but it is a calibre that every rifleman should use in his life time!
My favourite load was a stiff load of 4064 with a 55 grain Nosler bullet for deer and a 55 grain Sierra bullet for varmints. M.V. was 3900 fps with this load. I did win the biggest buck contest one year by using the 63 grain Sierra bullet.
Stay well my friend,
Franchi