Caribou Gear

Loading data for obscure cartridge

OntarioHunter

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I'm having a 404 Jeffrey built on a standard 98 Mauser action. It's been an interesting, albeit complicated, project. The 404 Jeff has a significant place in big bore history. Initially, the rimmed "nitro" cartridges in double rifles had a lock on 19th century dangerous game hunting. After the successful introduction of bolt action repeating military rifles, gun makers easily made them work for other four-legged thin-skinned animals. Obviously, the race would be on to build a magazined multi-shot gun for man-killers. W.J. Jeffery simply cut the rim off a Nitro case, made it rimless (rimmed cartridges don't feed well stacked in a box magazine), shortened the case, necked it down slightly (British govt banned export of .45 cal sporting ammo into the colonies because too many rebel types possessed surplus Martini-Henry rifles), and stuffed it into Paul Mauser's Model 1898. Jeffery introduced his .404 (actual bullet diameter is .423) sometime between 1905 and 1907. Mauser didn't answer the call for a true magnum action that could handle cartridges longer than 3" until 1910 (exclusively for Rigby). So, Jeffery continued to use 98s for the .404 until 1912 when they were given access to Mauser magnum actions. Stuffing fat and long .404 cartridges into an action designed for 8mm was the challenge. According to what I've read, Jeffery made several changes to the 98's "bottom metal" including eliminating the sides of the magazine box and widening the hole in the stock. I'm not that much of a purist. Two custom gun machinists make .375 bottom metal for Mauser 98 that they will will widen to take 404.

It's a great cartridge with enough punch to kill buffalo and even elephant when loaded with a 400 gr bullet @2150 fps. And that respectable punch comes at a relatively modest cost in recoil. 404 Jeff is not belted so it feeds smoother and has less case separation issues for reloading. Jeffery also originally offered ammo loaded with 300 gr pointed bullets for thin-skinned plains game (back in those golden olden days, getting close for a shot was considered more admirable than plinking at animals long range). In Africa the .404 survived the magnum revolution well, and it's seen a recent revival in North America ... but only in 400 gr offerings gassed up to match .416 Rigby. However, I am very reluctant to push the Model 98's action any harder than the original Jeffery factory loads. With modern advancements in bullet metallurgy I should be able to safely speed up 350 gr slugs and still match or exceed the punch of original 400 gr cup and core loads. The problem is no current factory loads seem to be offered in anything less than 400 gr and at velocities well above 2150 fps (at upwards of $20/round!). I have been able to find three exotic manufacturers of .423 cal bullets in 320 to 350 grs. Two makers sell unusual copper/brass bullets that look interesting: Cutting Edge's "Raptor" and Perrigrine "PlainsMaster." I already have a lifetime supply of 400 gr Barnes bullets, 38 new brass cases, and essentially new CH dies. I'd like to load some of the lighter copper bullets but having no luck finding loading specs. Not even on the company websites. Any suggestions?
 
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I'm having a 404 Jeffrey built on a standard 98 Mauser action. It's been an interesting, albeit complicated, project. The 404 Jeff has a significant place in big bore history. Initially, the rimmed "nitro" cartridges in double rifles had a lock on 19th century dangerous game hunting. After the successful introduction of bolt action repeating military rifles, gun makers easily made them work for other four-legged thin-skinned animals. Obviously, the race would be on to build a magazined multi-shot gun for man-killers. W.J. Jeffery simply cut the rim off a Nitro case, made it rimless (rimmed cartridges don't feed well stacked in a box magazine), shortened the case, necked it down slightly (British govt banned export of .45 cal sporting ammo into the colonies because too many rebel types possessed surplus Martini-Henry rifles), and stuffed it into Paul Mauser's Model 1898. Jeffery introduced his .404 (actual bullet diameter is .423) sometime between 1905 and 1907. Mauser didn't answer the call for a true magnum action that could handle cartridges longer than 3" until 1910 (exclusively for Rigby). So, Jeffery continued to use 98s for the .404 until 1912 when they were given access to Mauser magnum actions. Stuffing fat and long .404 cartridges into an action designed for 8mm was the challenge. According to what I've read, Jeffery made several changes to the 98's "bottom metal" including eliminating the sides of the magazine box and widening the hole in the stock.

It's a great cartridge with enough punch to kill buffalo and even elephant when loaded with a 400 gr bullet @2150 fps. And that respectable punch comes at a relatively modest cost in recoil. 404 Jeff is not belted so it feeds smoother and has less case separation issues for reloading. Jeffery also originally offered ammo loaded with 300 gr pointed bullets for thin-skinned plains game (back in those golden olden days, getting close for a shot was considered more admirable than plinking at animals long range). In Africa the .404 survived the magnum revolution well, and it's seen a recent revival in North America ... but only in 400 gr offerings gassed up to match .416 Rigby. However, I am very reluctant to push the Model 98's action any harder than the original Jeffery factory loads. With modern advancements in bullet metallurgy I should be able to safely speed up 350 gr slugs and still match or exceed the punch of original 400 gr cup and core loads. The problem is no current factory loads seem to be offered in anything less than 400 gr and at velocities well above 2150 fps (and upwards of $20/round!). I have been able to find three exotic manufacturers of .423 cal bullets in 320 to 350 grs. Two makers sell unusual copper/brass bullets that look interesting: Cutting Edge's "Raptor" and Perrigrine "PlainsMaster." I already have a lifetime supply of 400 gr Barnes bullets, 38 new brass cases, and essentially new CH dies. I'd like to load some of the lighter copper bullets but having no luck finding loading specs. Not even on the company websites. Any suggestions?
I don't know much about the Jeffrey except the RUM is based on it. So that makes it cool. But, call Steve at Hammer. I bet he can help with monos. mtmuley
 
I should add that 350 gr is more than enough to kill Cape buffalo. I shot two with 250 gr Barnes .375 monos and very impressed. First was at 110 meters which is very long shot for those critters. It went maybe twenty yards and tipped over. I just reweighed both bullets from second buff (see attached). One lost 2 gr and the other 8 gr.

I would probably shoot deer with it if ammo wasn't so expensive. I have seen muley carcasses shot with 45-70 and actually very little meat was damaged.
16816022262104011780486008303663.jpg
 
Looked at their site. Mt barrel isn't getting cut 1-20. Not close. 1-14 so I guess those bullets won't work.
If your twist will be 1 to 14 and the bullet needs 1 to 20, then they will do just fine. 1 to 20 is the minimum. - provided I read your post right, I couldn't find the bullet on the website.

Edit , I found it. Those will do well in a 1 to 14 twist barrel.
 
If your twist will be 1 to 14 and the bullet needs 1 to 20, then they will do just fine. 1 to 20 is the minimum. - provided I read your post right, I couldn't find the bullet on the website.

Edit , I found it. Those will do well in a 1 to 14 twist barrel.
Thanks! I was unclear exactly what is meant by "minimum." I found a couple of threads on African Hunter that seemed to indicate 1-14 would work in 404 Jeffery. I learned there's a difference between a bullet spin that's best for paper vs what works best for penetrating an animal.
 
Thanks! I was unclear exactly what is meant by "minimum." I found a couple of threads on African Hunter that seemed to indicate 1-14 would work in 404 Jeffery. I learned there's a difference between a bullet spin that's best for paper vs what works best for penetrating an animal.
Paper, or animal has nothing to do with twist rate.
The higher the number, the slower the bullet spins. It's only going 1 revolution for 20 inches of barrel travel. Versus the 1 revolution for 14 inches of barrel travel.
You match barrel twist rate for bullet length.
The longer (hence heavier) the bullet, the faster the twist rate is required to stabilize it.

If you "shoot" me your info i can run some numbers through Quickload for you.
Need COAL.
Barrel length.
Bullet your using.
Powder you want to use.
 
Paper, or animal has nothing to do with twist rate.
The higher the number, the slower the bullet spins. It's only going 1 revolution for 20 inches of barrel travel. Versus the 1 revolution for 14 inches of barrel travel.
You match barrel twist rate for bullet length.
The longer (hence heavier) the bullet, the faster the twist rate is required to stabilize it.

If you "shoot" me your info i can run some numbers through Quickload for you.
Need COAL.
Barrel length.
Bullet your using.
Powder you want to use.
The issue being I want to shoot 320ish gr bullets for plains game and 400 gr for dangerous game. Jeffery originally made their rifles to shoot BOTH 300 gr and 400 gr bullets. The lengths of those two are significantly different but as far as I know Jeffery only made one twist rate. Keep in mind this build is not intended to be a thousand yard tack driver. I suspect 16-1 with 6 lands will be a good middle of the road twist. Barrel length will be 24" (barrel maker finishes it at 28" but it will have to be threaded, reamed, cut, and crowned by gunsmith).
 
A whole different conversation, but there is a lot if thought out there that says the more stabilized a bullet is the better the terminal performance. mtmuley
It does kind of make sense that the p-force of the spin is also energy that must be absorbed or dissipated.

It is kind of cool to do the math on a bullet twist rate times velocity see what RPM your bullet is spinning. It's a lot.
This article talks about twist effects on terminal performance too. The author states that higher spin produces more heat, make the bullet more likely to upset on impact.
Cool idea, but I'm nerdy enough to want to see the science.


I wouldn't want to under-stabilize a dangerous game rifle. Tumbling solids and thick skin might make for a very grumpy Cape Buff. When in doubt, go to a faster twist.
 
1905 404 Jeffery.jpg
This is how Jeffery made 404 fit into a standard Mauser 98 action. No magazine box, just an end plate.
 
The issue being I want to shoot 320ish gr bullets for plains game and 400 gr for dangerous game. Jeffery originally made their rifles to shoot BOTH 300 gr and 400 gr bullets. The lengths of those two are significantly different but as far as I know Jeffery only made one twist rate. Keep in mind this build is not intended to be a thousand yard tack driver. I suspect 16-1 with 6 lands will be a good middle of the road twist. Barrel length will be 24" (barrel maker finishes it at 28" but it will have to be threaded, reamed, cut, and crowned by gunsmith).
Would it not work to just use the 400 grain on everything and call it good?
 
Would it not work to just use the 400 grain on everything and call it good?
The lighter bullets would have less recoil and that is always a concern with my eyes. More velocity would give me a bit more range.

I saw what copper 250 gr .375 H&H did to my two buffalo. I'm not convinced 400 gr is necessary to Cape buffalo with modern bullets. But I do have a bunch of 400 gr Barnes to get rid of.
 
My favorite things about the 9.3 is short copious blood trails and very little meat loss. I have yet to find a load it won't shoot well.
 
@OntarioHunter,

Is RCMP going to "allow" you to have said rifle?
Saw where the Ruger #1 is on the chopping block with that C21 bill, because someone had one made in 460 Weatherby, and that one rifle exceeds their energy limit.

Made me curious.
 
Ollin Magnetic Digiscoping Systems

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