I was 12 when my Father and I drew two elk tags for Island Park, Idaho. That was 1966. Dad had purchased an old "pre-36" Marlin, a top eject .38-55 from a co-worker. He also got four or five boxes of Remington 255 gr. factory loads with the rifle.
We spotted a herd of about 30 animals on the flats to the east of Bishop Mountain Fire Lookout and also a two-track off the main road, so we high-tailed it down there, then walked in the last three or four hundred yards, till we could see the animals in the small meadow. When the smoke cleared, one animal was down with an '06 hit, the other with the .38-55.
When we got the two rag-horn five points home, hung, and skinned them out, we found the Remington 255 bullet mushroomed under the hide on the off-side after having gone through both shoulders. It fell out when the hide was pulled back. Still weighed 230 grains. No bloodshot meat, the hole was straight and true through the tissue, and we ate the meat "clear up to the bullet hole".
Now, those loads were giving at best around 1600 fps, and in this rifle, with well worn, oversize bore, were likely giving a 'bit' less than that.
I wouldn't try it in an older lever gun, or blackpowder single shot, but that 235 gr. Speer, or the Hornady 220 spire point in a properly chambered .375 Winchester, at 375 Winchester pressure, SHOULD give 2000 fps+. Not something I'd try in a .38-55 case of anyone's manufacture, that have the same pressure limits as the .30-30. New .38-55 cases have the same web and base wall thickness as production run .30-30 cases, and .375 Winchester cases are a 'bit' beefier in those areas. That's for the W-W cases, can't say about the Starline brass. Pressure, by the way, for the .375 Winchester is around 52,000 psi, compared to a bit less than 30.000 psi for the best .30-30 loads, and a LOT less for 'safe and sane' .38-55 load data....
All I know is that that big 'ol bullet chugged through a whole lot of elk shoulder, made him really, really dead, and he tasted really, really good to a 12 year old sharing 'his' kill with the family that winter!