I am looking for a new barrel for my Marlin 44 carbine and I am undecided on twist. It will be a 44 mag primarily used for deer hunting and if opportunity arises black bear. I will be shooting jacketed bullets most likely 240xtps 270 speers and 300 xtps.

So the question is 1in 20 or 1 in 24 twist?

ask your barrel builder.......Pac Nor's chart suggests 1-18 as most common

It might be useful to review the SAAMI standards for the 44mag in rifle and pistol as there are significant differences and might go some way to explain why rifle shooters complain about accuracy of 44 mag in rifles.

A lot of the problems people have with cast in 44 mag rifles are due to rifles having looser barrel dimensions (0.431 vs 0.429) and the throating of rifle chambers (throat is too long). Twist is of lesser concern but rifles have a slow twist of 1 in 38" whereas pistols conventionally have much faster twists. To add a bit more confusion into the mix the 444 has a 0.430" groove, no throat and generally a 1 in 38" twist, though Winchester models with twists as fast as 1 in 12" have been made in 444.

If I were setting up a new barrel for a 44 mag rifle I'd go with a pistol spec barrel (0.429") and a custom throat that would just fit the cast designs i was intending to use. The twist on new Winchesters is around 1 in 26". I have been able to get good accuracy using 300gr cast pills in a 44 rifle whose barrel has a slow twist of 1 in 38" twist. In a new barrel I'd be happy to use any twist from 1 in 18" through to 1 in 26".

If you adopt tighter barrel and chamber specs you are likely to have to ease up on max loads somewhat.

I'd go 1/20. I've used barrels with that twist and 300 grain bullets stabilized great.

A twist faster than what you need don't hurt things as bad as too slow of a twist.

. I would stay with the factory twist of 1: 38. I have several 45 Colt and 44 Mag rifles and they are very accurate with bullets up to and including 300 grain. If I need a heavier bullet than 300 grain, I use a larger gun, a 45-70, 444, or something.

better to over twist.....than under twist......

or as mentioned get a 444 or better yet a 45-70

I went with a 1:24 twist. The twist calculators say 1:29 or 1:30 would be enough, so I figure the 1:24 would be enough.

My experience with 2 marlin 94s in 44, was that as much as I tried I couldn't get 270 and 300's to shoot as well as the 240's in the 1:38. I did consider about a guide gun in 45/70 as the rebarrel on the 94 would be nearly the same cost but I like the way the 94 carries better than the guide gun and the 44 mag is plenty of power for my application.

so in the end I an going with a stainless 1:24 and I will get the whole gun cerakoted.

my Marlin 1894 has a factory 1:38 twist. It is very accurate with the only load I use, a 270 grain Speer Gold Dot SP over H110 powder.

my ruger has a 1:20 and has shot everything Ive tried very well including 300grainers. I mostly shoot 240's though

1-20 at least. Writer Brian Pearce has been nagging both "Marlins" on this for years. Can't get 'em to see the light. Rugers and my Browning Low Wall are 1-20.