Cartridge length might be a big one. It has to cycle through a lever action which would require the bullet to be seated deeper. I have a book called big bore rifles where an author made up a 444 single shot with a 1 20 twist and ran all sorts of bullets through it. Single shots are not as limited.
If you can find a bullet that will cycle you can make it work with that twist. Performance on game is very subjective.

DEP

 

First off only the 1-20 twist guns can handle 400+ grain bullets, the 1-38, 360 grains is max!
Number two, Handloading 400gr Hardcast bullets is not plug and play, the 400gr bullets are very long, the 444 case is tapered, you cannot just load the bullet in the case, or it would be too wide to chamber, so you must get a Special made reamer to ream the inside of the case to accept the bullet diameter! So case life is much shorter, and getting an even tapper in the case is, not a guarantee!
personally, You don’t gain anything from a 400gr bullet going to a 350gr bullet, in terms of performance, our Ranch Dog Mold in 350gr, gets 2000fps, VS a 400gr going 1750fps, and NO Special loading needed!
No one I know that tried the 400gr bullets stuck with them in a OEM Marlin 444!

 

First off only the 1-20 twist guns can handle 400+ grain bullets, the 1-38, 360 grains is max!
Number two, Handloading 400gr Hardcast bullets is not plug and play, the 400gr bullets are very long, the 444 case is tapered, you cannot just load the bullet in the case, or it would be too wide to chamber, so you must get a Special made reamer to ream the inside of the case to accept the bullet diameter! So case life is much shorter, and getting an even tapper in the case is, not a guarantee!
personally, You don’t gain anything from a 400gr bullet going to a 350gr bullet, in terms of performance, our Ranch Dog Mold in 350gr, gets 2000fps, VS a 400gr going 1750fps, and NO Special loading needed!
No one I know that tried the 400gr bullets stuck with them in a OEM Marlin 444!

He commented that he had a 1-20" twist. I have seen some single shots in 444. AS to the tapered case, probably the same limitations in 45 70 cases as it is also tapered. Long range target shooters use 500+ grain bullets, but in single shots where they can use a long bore riding nose. The 444 could also do that but not cycle in a lever. Same limitations in a 45 70 lever which is why they are not competitive with the single shots.
444 never made much sense to me. It was a resurrection of a black powder type cartridge, most of which became obsolete. It has some very loyal followers but the 45 70 is still being manufactured and it is not. Bullets in the 300 to 350 class were best used in the 38 and 40 calibers. 40 90 was a popular buffalo
cartridge in its day as it used those bullet weights very well and they hit harder than from a 45 using the same bullets and did recoil less. Winchester made several Express" bp cartridges for their levers that used relatively light bullets and slow rifling. Probably fouled less. They did give more velocity from the limitations of BP. Heavy bullets work best on critters like moose and the big bears that I don't get to hunt. For that the 45 70 is just plain suprerior.
A 240 grain + bullet will hit hard on deer at about any range you can hit them with using a 444. Heavier bullets will work but compare them to a 35 Whelen or a 9.3X62 at longer range and they fall short. I thought about getting a 44 mag once but my 38 55 will out shoot one down range. The 405 Winchester went obsolete and it is a far better cartridge than the 444. Lost out to the cartridges like the 9.3 just mentioned due to down range performance. Some like the large bores and enjoy shooting them, but not enough to keep the 444 healthy. I traded my 45 70 lever in for a 38 55 lever and never regretted it.

DEP

 

The bigger you go the slower you go( and more recoil).........I shoot 300's.

 

He commented that he had a 1-20" twist. I have seen some single shots in 444. AS to the tapered case, probably the same limitations in 45 70 cases as it is also tapered. Long range target shooters use 500+ grain bullets, but in single shots where they can use a long bore riding nose. The 444 could also do that but not cycle in a lever. Same limitations in a 45 70 lever which is why they are not competitive with the single shots.
444 never made much sense to me. It was a resurrection of a black powder type cartridge, most of which became obsolete. It has some very loyal followers but the 45 70 is still being manufactured and it is not. Bullets in the 300 to 350 class were best used in the 38 and 40 calibers. 40 90 was a popular buffalo
cartridge in its day as it used those bullet weights very well and they hit harder than from a 45 using the same bullets and did recoil less. Winchester made several Express" bp cartridges for their levers that used relatively light bullets and slow rifling. Probably fouled less. They did give more velocity from the limitations of BP. Heavy bullets work best on critters like moose and the big bears that I don't get to hunt. For that the 45 70 is just plain suprerior.
A 240 grain + bullet will hit hard on deer at about any range you can hit them with using a 444. Heavier bullets will work but compare them to a 35 Whelen or a 9.3X62 at longer range and they fall short. I thought about getting a 44 mag once but my 38 55 will out shoot one down range. The 405 Winchester went obsolete and it is a far better cartridge than the 444. Lost out to the cartridges like the 9.3 just mentioned due to down range performance. Some like the large bores and enjoy shooting them, but not enough to keep the 444 healthy. I traded my 45 70 lever in for a 38 55 lever and never regretted it.

DEP

He commented that he had a 1-20" twist. I have seen some single shots in 444. AS to the tapered case, probably the same limitations in 45 70 cases as it is also tapered. Long range target shooters use 500+ grain bullets, but in single shots where they can use a long bore riding nose. The 444 could also do that but not cycle in a lever. Same limitations in a 45 70 lever which is why they are not competitive with the single shots.
444 never made much sense to me. It was a resurrection of a black powder type cartridge, most of which became obsolete. It has some very loyal followers but the 45 70 is still being manufactured and it is not. Bullets in the 300 to 350 class were best used in the 38 and 40 calibers. 40 90 was a popular buffalo
cartridge in its day as it used those bullet weights very well and they hit harder than from a 45 using the same bullets and did recoil less. Winchester made several Express" bp cartridges for their levers that used relatively light bullets and slow rifling. Probably fouled less. They did give more velocity from the limitations of BP. Heavy bullets work best on critters like moose and the big bears that I don't get to hunt. For that the 45 70 is just plain suprerior.
A 240 grain + bullet will hit hard on deer at about any range you can hit them with using a 444. Heavier bullets will work but compare them to a 35 Whelen or a 9.3X62 at longer range and they fall short. I thought about getting a 44 mag once but my 38 55 will out shoot one down range. The 405 Winchester went obsolete and it is a far better cartridge than the 444. Lost out to the cartridges like the 9.3 just mentioned due to down range performance. Some like the large bores and enjoy shooting them, but not enough to keep the 444 healthy. I traded my 45 70 lever in for a 38 55 lever and never regretted it.

DEP

He commented that he had a 1-20" twist. I have seen some single shots in 444. AS to the tapered case, probably the same limitations in 45 70 cases as it is also tapered. Long range target shooters use 500+ grain bullets, but in single shots where they can use a long bore riding nose. The 444 could also do that but not cycle in a lever. Same limitations in a 45 70 lever which is why they are not competitive with the single shots.
444 never made much sense to me. It was a resurrection of a black powder type cartridge, most of which became obsolete. It has some very loyal followers but the 45 70 is still being manufactured and it is not. Bullets in the 300 to 350 class were best used in the 38 and 40 calibers. 40 90 was a popular buffalo
cartridge in its day as it used those bullet weights very well and they hit harder than from a 45 using the same bullets and did recoil less. Winchester made several Express" bp cartridges for their levers that used relatively light bullets and slow rifling. Probably fouled less. They did give more velocity from the limitations of BP. Heavy bullets work best on critters like moose and the big bears that I don't get to hunt. For that the 45 70 is just plain suprerior.
A 240 grain + bullet will hit hard on deer at about any range you can hit them with using a 444. Heavier bullets will work but compare them to a 35 Whelen or a 9.3X62 at longer range and they fall short. I thought about getting a 44 mag once but my 38 55 will out shoot one down range. The 405 Winchester went obsolete and it is a far better cartridge than the 444. Lost out to the cartridges like the 9.3 just mentioned due to down range performance. Some like the large bores and enjoy shooting them, but not enough to keep the 444 healthy. I traded my 45 70 lever in for a 38 55 lever and never regretted it.

DEP

He commented that he had a 1-20" twist. I have seen some single shots in 444. AS to the tapered case, probably the same limitations in 45 70 cases as it is also tapered. Long range target shooters use 500+ grain bullets, but in single shots where they can use a long bore riding nose. The 444 could also do that but not cycle in a lever. Same limitations in a 45 70 lever which is why they are not competitive with the single shots.
444 never made much sense to me. It was a resurrection of a black powder type cartridge, most of which became obsolete. It has some very loyal followers but the 45 70 is still being manufactured and it is not. Bullets in the 300 to 350 class were best used in the 38 and 40 calibers. 40 90 was a popular buffalo
cartridge in its day as it used those bullet weights very well and they hit harder than from a 45 using the same bullets and did recoil less. Winchester made several Express" bp cartridges for their levers that used relatively light bullets and slow rifling. Probably fouled less. They did give more velocity from the limitations of BP. Heavy bullets work best on critters like moose and the big bears that I don't get to hunt. For that the 45 70 is just plain suprerior.
A 240 grain + bullet will hit hard on deer at about any range you can hit them with using a 444. Heavier bullets will work but compare them to a 35 Whelen or a 9.3X62 at longer range and they fall short. I thought about getting a 44 mag once but my 38 55 will out shoot one down range. The 405 Winchester went obsolete and it is a far better cartridge than the 444. Lost out to the cartridges like the 9.3 just mentioned due to down range performance. Some like the large bores and enjoy shooting them, but not enough to keep the 444 healthy. I traded my 45 70 lever in for a 38 55 lever and never regretted it.

DEP

Mebbe so.......Opinions are like exhaust pipes......We all got one............My .444's are working/hunting guns.......My 45/70's are range toys.

 

OP: see here: Beartooth Bullets > Tech Notes > .444 Marlin- America's Most Versatile Big-Bore Part III

There is load data for Beartooth’s 405 grain bullet at the link. It’s also in a sticky at the top of the 444 forum. The article is 20-plus years old, Beartooth is defunct and some folks would consider the load data to be ambitious so use caution. But it should give you a starting point and some useful information. I’ve only gone to 330 grain myself and had very good results but I’d be curious to hear how you make out.

 

Thanks fellas 350 sounds fine then. As to 45-70 vs 444 I have never seen a 444 thread that didnt have the 45-70 poke its head in lol. Not sure why that is. I see the advantage of 444 being able to utilize my whole stock of 44 mag pistol bullets that are cheaper than anything jacketed in 45-70 or 35 whelen etc. Can also share brass with my 410 shotguns.

 

I'm a fan of the .444 but I don't personally have need of 300+ grain bullets, although if I ever would hunt moose I'd look into those. Nice to know the cartridge is that versatile though. I'm happy with decent 240, 265 (Hornady flat point) and 270 grain (Federal Hammerdown) loads. In fact the Federal Hammerdown loads are the most accurate I've shot, although they don't have the velocity of the factory Hornady Superperformance loads. Even though they only chronograph at 2170 fps I don't think they'll bounce off a whitetail.

 

How long is your barrel? I checked my chrono notes and I got 2275 fps average from the HammerDown last summer (granted it was a hot day) out of my 22 inch Ballard rifled 444.

 

The loyalty to the 444 reminds me of similar posts about the 30 30. Personally I think it is the combination of rifle and cartridges not just the cartridge. I own 7 Marlin lever actions, one Mossberg 464 and a Rossi 357. My "working" gun is generally my 6.5 CM Ruger Predator. Mostly because I sit over a hay field and the shots are long er than I like with lever action cartridges. They would work but it's stretching them.
From what I have read the 444 was supposed to be an improvement over the shortcomings of the 44 magnum. Longer range and better on elk. Came out with a 44 mag barrel with a 1 38 twist and used pistol bullets which many felt were too soft. Case can use the 44 mag bolt face. It has developed a loyal following because it works fine for most of you and is enjoyable to use. I could make arguments about the tube fed lever actions being obsolete but they are enjoyable to hunt with. I also own a lever 22 magnum and a single action 45 Colt.
As long as the utility of the cartridge meets the enjoyment of the rifle it's a fine cartridge. My 45 70 is a repro Rem rolling block with a 28" barrel that weighs about 12 pounds. I don't do much BP cartridge hunting anymore. At 74 years I just set in my stands. Used to use my levers still hunting. Should have tried it last year.

DEP

 

Here are two Accurate Molds 350 grain moulds. The first one at first glance looks pretty similar to the Ranch Dog specs but I haven't compared them back to back.

Bullet Design Details | Accurate Molds

accuratemolds.com

Bullet Design Details | Accurate Molds

accuratemolds.com

 

Thanks for this, @444afic ! I just stumbled upon this confirming thread, too, which I'm not sure how I missed before:

https://www.marlinowners.com/threads/ranch-dog-moulds.120949/page-2#post-1435609

 

Just saw these on MTB's website:

Montana Bullet Works

I think they're new, or if they're not, I missed them on their website. I assume one would need a Lee FCD to crimp them at an OAL short enough to feed in the 444.

Edit: they look very similar to Beartooth's 355 grain WLNGCDCG bullet