there is a whole new round of smackers to come...jeffeosso is making a whole new round of carts based on a slightly shortened rum case to fit a regular 7mm rem mag 300 win mag or 338 wm ect the calibers will be as follows 470 ar,458 ar,416 ar,375 ar,9,3 ar,358 ar,338 ar,8mm ar,308 ar,7mmar, 270ar, 264ar, 257ar and 243ar

it is still in the smithing stage but testing will come soon. if you want to help out so he does not have to charge to send out the reamer send him a donation. if all his costs are taken care of he will let us use the reamer for free. i think a $20 donation from a bunch of us should take care of it. more than a few have expressed intrest in it and its not hard to see why these are good rounds. lots of capacity, fits standard action, cheep brass ect ect. if you have fallen out of love for a gun that is taking up space in the safe turn it into a real thumper! immagine a 375 more powerfull than the h+h in a handy rifle...a cart better than the 416 taylor on par with the 416 rem...have a short capstick that you can plink with pistol bullets or spit out 500 grain elephant killers! anyway cheer him on, start a new project and maybe pledge here to give him $20 to take care of his costs...check out the threads on the big bore board

p.s. a.r. IS for accurate reloading

p.p.s. can you immagine how fast a 243 cal will go out of this

so far we have pledges from me
vapodog
577nitroexpress

Boom,

I know you guys have been working yourselves into a uproar over on the big bore forum....BUT
that 458 AR looks an awful lot a 460 Van Horn without a belt. Which by the way didn't really work out as advestised a little short on velocity from what was expected from what I recall, but I suspect the original would have worked out better with a little more barrel. Another issue is a 100 grains plus powder capacity is pretty nasty overbore for 375 cal and below.

One last question who picked the shoulder angle? It looks like it was figured out for the 470 above for headspace. Migrating this down to smaller bores I would rather see 17-27 degree, add body taper to loose about 20 grs of powder and make it feed better.

That baby in the 243, and 257 bore should be good for about 200 rounds before you need a new barrel. I don't mean to rain on your parade on this one Boom but I am not convinced its really practicle in the medium bores. Another item I don't really care for is the magazine box details, the amount of fiddling around with the magazine is certainly not worth the gain on this overbore concept. A 375 H&H modified case is all the case needed down in the smaller bores, above that its just a lot of powder for little gain, and the only way this would really work out is in a 28" barrel, otherwise you have just reinvented the flame thrower.

I think I will wait till the movie comes out.

he is just covering his bases that is why he is going all the way down to the 243...the testing will come soon and i think they will be pretty good considering all the factors. you can rain on the parrade as long as you pledge $20

in fact lets make that the rule...any negativity and you get taxed $20 for the research and development...we'll let the first one go on a warning

My hunting partner has a reamer for nearly exactly this cartridge in .257, he shortened .300 RUM so it would fit on standard magnum length actions. He requires 4 dies to get it down and then fireform. He calls it the .257 Wraith. He has done a lot of research into it as well.

IV

interesting...have him email jeffeosso...i am sure they would have a bit to chat about and learn

quote:

Originally posted by boom stick:
so far we have pledges from me
vapodog
577nitroexpress

PM me with a mailing address and I'll send the $20

quote:

Originally posted by schromf:
Boom,

I know you guys have been working yourselves into a uproar over on the big bore forum....BUT
that 458 AR looks an awful lot a 460 Van Horn without a belt. Which by the way didn't really work out as advestised a little short on velocity from what was expected from what I recall, but I suspect the original would have worked out better with a little more barrel. Another issue is a 100 grains plus powder capacity is pretty nasty overbore for 375 cal and below.

One last question who picked the shoulder angle? It looks like it was figured out for the 470 above for headspace. Migrating this down to smaller bores I would rather see 17-27 degree, add body taper to loose about 20 grs of powder and make it feed better.

That baby in the 243, and 257 bore should be good for about 200 rounds before you need a new barrel. I don't mean to rain on your parade on this one Boom but I am not convinced its really practicle in the medium bores. Another item I don't really care for is the magazine box details, the amount of fiddling around with the magazine is certainly not worth the gain on this overbore concept. A 375 H&H modified case is all the case needed down in the smaller bores, above that its just a lot of powder for little gain, and the only way this would really work out is in a 28" barrel, otherwise you have just reinvented the flame thrower.

I think I will wait till the movie comes out.

No raining here friends ......I'm a cheerleader....However, I too suspect the usefulness of this cartridge falls in the .308 caliber and up.

I found a stash of .375 RUM cases locally that I'm going to pick up just to be ornery. The .375 AR does seem to be a "leg up" on the .375 Taylor and that does seem to hold interest to me. Besides I have two M-70 actions sitting here wasting closet space. One in .300 Win Mag and the other in .338 Win Mag

I must also say that there's only three contributors so far.....let the cards fall as it may.

I'd be happy to contribute to projects that interest me and there's a bunch of them....this is just one.

Pm me the address and to whom.

Interesting concept. I wish there were PCs when I started wildcatting.The good news is that it is not too late to make me a contribution. roger

The shoulder angle was chosen with talking to dave manson, at manson reamers. the consistant datum is to have a single set of headspace gages, and to have a single set of dies.

for example..
a single set of reamer and gages is $250...
a set of reamer, 2 conversion neck and throat reamers, and a single set of headspace gages is $450 vs 750 for more reamers.

the 30's will be a different headspace... but that's another day

jeffe

These sound a lot like Dakota mags?

cheap as heck though...

the poor mans dokota, jeffeosso wont charge you for the reamer. rechamber maybe rebarrel plus clean up and cheap brass...cant wait for the tests

thanks bartsche...keep it going guys

The intent of the design is to get a maximum case capacity big bore that will fit in a generic belted mag action, with minimal gunsmithing and using inexspensive brass.

Since the rem ultra mag brass has the same rim dia as the belted mag case, no bolt or extractor work is needed. Since the case body is essentially the same dia as the belt, the magazine and feed rails should need no work.

I guess you could say the intent of the design is to take the chatfield/taylor design philosophy, but increase the case capacity to get the full length mag performance.

Yes, there have already been a slate of wildcat and proprietary designs on the shortened 404 Jeffrey and 416 Rigby cases, but they require more expensive brass on the 404 case, and more expensive brass as well as signifigant gunsmith work on the 416 Rigby case.

The case was improved, ie straightened out to provide a sufficient shoulder for the 470 case, which really was the whole starting point for this design. There really aren't many options for a .475" magazine rifle that can launch a 500 gr bullet @ 2200 fps, there is the 470 Capstick on the full length H&H case, and a few designs on the 416 Rigby and 460 Wetherby, but those limit your action choices, and with the bigger cases, raise the cost of brass.

Personally I'm less interested in the under 40 chamberings, but I just may end up building a 470 as well as a 416.

That was what my partner was hoping for (.257 Dakota) but he misjudged how far the brass would stretch. When he first received the rifle he was using 7mm Dakota brass and having numerous problems, he then switched to necking down and shortening .300RUM brass (he could use 7RUM brass but 300RUM is much more available) The other problem he had was not neck turning down far enough, this caused pressure problems and 2 trips to the gunsmith until he finally figured out that the pressure was coming from the neck size and not the load itself....

IV

The more I read about this the more it makes sense from a over .30 cal view point. Good idea whoever thought about it. Reasonably cheap brass and I would hope the dies would be semi inexpensive.
Can Jeffesosso also make reloading dies?

quote:

Can Jeffesosso also make reloading dies

Nope..
BUT... as soon as the prints are finalized for the reamer, they will be sent to CH4d (long term cross business relaionship there) and the dies can be ordered. less than $200

jeffe

The plan is to have CH4D make the dies, I'm guestimating the'll be in the $80-100 range, though I haven't confirmed that with Jeff.

If was Jeff's idea, I just kept encouraging him and providing some design ideas to make it work, mostly the motivation to say it would work.

quote:

Originally posted by vapodog:
[QUOTE]Originally posted by schromf:


I must also say that there's only three contributors so far.....let the cards fall as it may.

I'd be happy to contribute to projects that interest me and there's a bunch of them....this is just one.

Don't let the number three scare you; a lot of us just don't publicly post our support on everything we like.

True, True

OK, so the theory is definately sound. I built the .257 Wraith. My case length is 2.6830 w/37 deg. shoulder. The Reamer is form David Kiff. The forming dies came from CH-4D at a cost of $400.00. I have a 6.5mm and a 7mm prototype.
Let's clear the air once and for all about barrel life. 1. Use stainless steel or if you can find is Bofors steel. 2. Have your reamer maker machine the lead amgle into the throat at 1 deg. 30 minutes, (Kiff does this) this lead angle will lend itself to considerably longer throat life. 3. a 3 or 4 groove barrel, (three grooves is best) wider lands resist burning up, distorts the bullet less helping the ballistic coeficient and for those of you who love to shoot X Bullets this groove geometry appears to allow these bullets to group well. 4. don't heat your barrel up to the point that you cannot keep your hand on it, yes, your shot strings may take longer. Given the cost of a barrel and then the fitting and bedding it just does not make any sense to be impatient and potentially shorten the life of a barrel and/or throat. 5. Keep your barrel clean.
I wanted arifle that would cleanly engage game out to 500 yards, it does. It shoots 100 grain bullets at over 4,100 fps. and I am not oushing the pressures. Yes my barrel is 30" long, 28" would be a minimum, a 26" would be the absolute minimum, however the 150-200 fps. difference in velosity is nice.
Now, when one gets below 6.5mm bore diameter your powder is restricted to the slowest burn rate(s). and not extruded powders, they can cause neck bridging and pressure spikes. Suitable powders are H-870, AA8700, WC 860, WC 872, etc. 6.5mm and above extruded powders are fine.
I own the reamers, the go and no-go gauges and the forming dies.
The bigger the bore diameter, the less the barrel length needed vs case capacity, for instance the 300 RUM needs a 28"-29" barrel the really make the most of the power available. Most folks buy and use the factory 26" barrel and are pleased.
The .30 cal. version would do well in a 26", personally I would prefer a 28", but the case capacity is less than a 300 RUM and the velocity potential would be nearly equal since the smaller case would make more efficient use of the available powder and barrel length.

If you have questions, let me know.

Interesting!

I've wanted to necked up a 375 Rum case to 475 with no other changes for several years now.

Could the shorter 338 Rum case be used instead or would the neck get to thin?

I'll keep an eye on this thread.

Snapper