How extensive is the work required for a 404 Jeff on a 1903 Springfield action?. Worth doing or chamber for another cartridge in my Springfield action ?

I've been thinking of a 400 Whelen on that action for simplicity but have the bug for a Jeff someday too. I have a Springfield action that needs a job and I need a gun project this winter.

it should work out okay, but a 10,75x68 would be all that much easier. ejecting live rounds will be the hang up .. ask Duane to make you a bottom metal ..

Do I need new bottom metal or is that a want?

it would be a nearly required for me .. it could work, but, hey, just get one that you know will work and be done with it.

at least for me

Ok, i'll preface with I'm not a gunsmith and have not handled a 404 jeffery round, that said...

I have a springfield that the original magazine has been taken out about as far as is safe/prudent to do. The 416 Taylors when stacked in there start to cross a little bit, meaning they aren't laying in just the way they're supposed to. A 404-375 was discussed, shortening a 375 case, blown out (no shoulder) to accept a .423 bullet. It would work great in there.

all that just to say, you may need a new magazine. ?? I'll follow this with interest, there are too few large bores made on springfields.

Red

I've built a 416 AR on one.. Mike Jines as a 458 winmag on one ..
i've built on springfields
416 AR
358 win
300win
30-06 AI
308
257 JLS (wsm)
257 roberts

Jeffe, what do you think about a 375 Ruger? I have a brand-new never-fired 375 H&H barrel fitted/chambered for a Mauser but have no spare Mausers. I DO have a 1903 and have considered this several times in the H&H chambering but didn't want to hassle with the mag length issue.

IOW, IYO, using the original 1903 bottom metal, would it be easier to lengthen the mag for the H&H or try to get the mag box/rails to feed the Ruger case shoulder OK?

Not trying to hijack the thread but my orphan bbl is in 375 and not 404.
Regards, Joe

Joe,
I think the 375 ruger is a great round .. in a high number 1903 --- it would be zero more work than making a springfield a 30-338 or 308 norma .. which is to say, not difficult at all.

Thanks Jeffe. I've done a very few of the belted mags on 1903s with, as you say, little difficulty. But my previous conversions were all smaller bores, 26-30 cal, with shorter and slimmer bullets. Plus, I've never actually held one of the new Ruger cartridges and I just finished reading some mumbo-jumbo article about the 'magic' new case shoulder shape. Just wondered about case dimensions. Now, to find a reamer....
Regards, Joe

base is .532, same as a belt .. should is about the same as a 300win ... use 225gr hornady SPBT bullets, which are toughenough ... it will feed at least as good as RN 300wizbang