You really should have started your own thread.
"...any one ever loaded Speer 110 hollow point varminter in an M1 Carbine..." Nothing but Speer 110 grain HP's for eons. My rifle likes IMR4227 and regular small rifle primers. 13.5 to 15.0(compressed) No feeding issues whatsoever, that a bath didn't fix.
"...with H100 powder..." H110? Tried it, long ago. Get better accuracy with the IMR4227.