January/February Rifle Magazine has an article page 30 called A .444 SMLE. The author bought an Apex 1in 18" twist barrel and put on a Weaver scope and Fajen Reinhart sporter stock.

With the 190gr. Lee Wadcutter bullet and 5gr. of "Bullseye" made a ragged hole at 40yards right on the + hairs that were set for 265gr. Hornadys at 100yards.

Making a sheet metal inner magazine helped with the feeding problems.

As the rims are almost the sme size, bolt thrust would be less for the straighter case, so and load suitable for a Marlin, would work for the SMLE - in other words, up to 2,200fps with 300gr. bullets with the right powder. Not bad for a 2.2" case and an old 'beater'.