Trying to figure out your reamer .... a short 405 win .... but the 412 x 2 has a belt on it ????
Trying to figure out your reamer .... a short 405 win .... but the 412 x 2 has a belt on it ????
Been busy with a new to me RCBS A3, may get to look in the pile tomorrow, and yes I'm a boat guy. Not putting in the softwater boat this year, too much drama/silliness going on. Normally my life is as about drama free as you can get, it's getting shoved in my direction, even though I am doing my best to stay
out of it.
Avatar is the real boating I do, softwater stuff is just killing time until the ice comes back:
https://www.youtube.com/watch?v=X9VEM4KdgSY
To avoid needing a custom reamer, the 412x2” can use a 405 Winchester reamer to cut the chamber length... 2”.
After the two inch length is reached, a boring bar can cut the belt’s recess to a depth of .220” from the bolt face.
If you look at cartridge drawings, get the 240 Weatherby and you’ll see the belt’s dimensions... Now look at the 405 and add the forward 1.780” to that belt drawing to get the 2” total.
That’s why a shortened set of 405 Winchester can seat the bullet and size to the top of the belt.
Full length sizing should be easy using a standard 240 Weatherby FL die, whose shoulder begins past the 2” length, but the shortened 405 W seater die is still the easy choice for a bullet seater die.
The NOE expanders will round out the loading necessities.
Last edited by cainttype; 07-01-2019 at 11:49 PM.
Are the 240 weatherby dies sufficient to form the belt it is a special belt forming die needed
A special belt-forming draw die is needed to form a clean, sharp-edged belt.
Once-fired commercial brass has been better than unfired new brass, and has proven to need nothing more than expanding the neck to meet the dimensional requirements. Some mil-surp necks are thicker so, depending on the chamber’s final exact measurements, they might need reaming... The commercial brass has been spot on.
Expanding could be done on a series of small steps to larger diameters, but I have a looooooong expander a friend made for me that goes from .308” to .408” in a single pass... So far, I’ve not annealed any necks and the splitting rate has been about 5%, so not too bad.
A really stout press is needed to draw the belt. I use an RCBS A2 as a preference.
The draw die uses an ejector rod that is hammered from the top to push the new case out after fully forming the belt...Good lube, and plenty of it, is a necessity.
Standard shellholders are not used. The set-up uses a pusher-type adaptor to drive the case into the die, then the ejector rod is inserted through the top to drive the case out with a hammer, or small maul.
Reducing the thickness of the case base so the brass can be used to create a belt reduces the potential case strength at the location where it is most critical, all for the sake of fashion.
That’s incorrect.
Case walls at the reduced area are actually thicker than original. Nothing is removed, and walls get thicker as the diameter is reduced using a draw die.
The belt is used as a positive headspace when using bullet diameters that are too large for simply necking up. It also creates “straight-wall legal” cases where bottle-necks are banned.
Having a large bore “cast bullet-friendly” chamber in a modern short-action bolt action carbine, using a very efficient case capacity for cost effective fun is a hard thing to find... Try locating a .400”+ diameter cartridge, with less powder capacity than a 308 Winchester for efficiency, designed to work in a standard “short action” bolt action rifle... a short-to-medium range thumper that is cheap to reload... Good luck with that.
Lastly, by using a belt you can chamber a modern box magazine rifle (like a Remington 700) to work without bolt modifications. The belted .412x2” works in a standard action from a donor rifle originally chambered 308 Winchester, 243, etc...
RCBS and others used to make a case forming die to create a "belt" on a 30-06 case, as part of a set to convert 30-06 cases to 240 Weatherby Magnum.
I once held that particular die set in my hand and I'm still annoyed that I didn't take it home!
It was on the shelf of Ray's Sport Shop in Plainfield, NJ, but as they've been out of business for a decade...
(Since the death of Ray, I presume)
A rimless 444, shorten to whatever length you need/want can be made from 30-06, 8x57, 308 depending. The rimless 444 headspaces on the case mouth. The rimless 444 was built for military Mauser conversions. There are many 300 grain bullets that work well, with 325, 350 and heavier available. I think RanchDog worked on a 350 for the 44. If you just want SOMETHING DIFFERENT, that is fine but it is quibbling to believe there is a significant difference is killing or penetration between 412 and 432 bullets of the same weight and construction. Shoot enough stuff and you will find that there is no magic to ANY caliber. Proper placement of a 'PROPER' bullet is the key. If just doing something different, again that is fine but don't justify on false premise, just build it because you want it.
The 45 Raptor, 450 Bushmaster, and new 350 Legend all headspace on the mouth, too.
The 450 Marlin is a standardized version of Nonte’s 458x2” American with an exaggerated belt, technically both headspace on the belt.
The OP was referring to belts being drawn on 30-06 cases, basically forming a 240 Weatherby head...From that point, you’re almost restricted to bullet diameters less than .429”, which would leave a pretty thin neck wall even if there was zero taper above the belt... .412” is a natural maximum diameter to keep neck walls at roughly .015” and headspacing on the belt.
If interest was in anything .375” or less, the standard 308 case would be the best option unless you needed a “straight wall”, or wanted to slightly reduce case capacity.
Last edited by cainttype; 10-29-2019 at 05:58 AM.
I was looking at my stash of brass and found two box's of nos "Remington umc 300 magnum". This is not 300 Winchester magnum brass. I believe it is from the 50's-60's. The head stamp is "REM-UMC 300 MAGNUM". This brass looks like a 30-06 belted magnum. It has a slow taper shoulder. I have no idea when or where I got these shell from. Doing research has proven to only find one picture on the internet nothing else. https://www.oldammo.com/300AMU2.jpg Ah picture worked!!
Last edited by rcslotcar; 11-12-2019 at 09:59 PM.
It seems odd today, but for a long time there was only one “300 Magnum”, the H&H.
Introduced in the mid-twenties (it wasn’t until the early-mid sixties that Winchester introduced the 300 Win Mag based on the same case), it was pretty much legendary.
I’d guess that your cases were made before the other 30 Mags arrived, in a time when “300 Mag” wasn’t used in a dozen varieties, so there wasn’t a need to specify “H&H”... somewhere between 1925-1963.
Did P.O. Ackley do something like this?
BP | Bronze Point | IMR | Improved Military Rifle | PTD | Pointed |
BR | Bench Rest | M | Magnum | RN | Round Nose |
BT | Boat Tail | PL | Power-Lokt | SP | Soft Point |
C | Compressed Charge | PR | Primer | SPCL | Soft Point "Core-Lokt" |
HP | Hollow Point | PSPCL | Pointed Soft Point "Core Lokt" | C.O.L. | Cartridge Overall Length |
PSP | Pointed Soft Point | Spz | Spitzer Point | SBT | Spitzer Boat Tail |
LRN | Lead Round Nose | LWC | Lead Wad Cutter | LSWC | Lead Semi Wad Cutter |
GC | Gas Check |