Andrew Massi
Well-Known Member
Us869
Cranking up the RPM
- Thread starter Swamplord
- Start date
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Axl
Well-Known Member
I'd call it "Rip eM"!
77.0 gr of it was in each case that I pulled apart, not sure what kind of powder
A heads up to 35 cal fans, I'm currently working out an optimum high bc bullet weight for available fast twist barrels in 35 cal and will have Badlands make me a high bc hunting bullet in the awesome new Super Bulldozer ll design, I tested the 205 gr in 30 cal on a nice moose in Sept with fantastic results,
I feel that we need one in .358" too !
min order for a custom bullet is 500 pcs, if anybody is interested in this bullet we can all pitch in and get the bullet made sooner
I feel that we need one in .358" too !
min order for a custom bullet is 500 pcs, if anybody is interested in this bullet we can all pitch in and get the bullet made sooner
74sharps
Well-Known Member
Lurking on the sidelines with this one. Looks very interesting. Could be a big improvement for several calibers. One kind of popped into my head...
In between the .358 and the .375, this cartridge would make an awesome 9.3.
Possibly out do the Sako version and maybe the 9.3x64. Keeps ones wheels turning.
In between the .358 and the .375, this cartridge would make an awesome 9.3.
Possibly out do the Sako version and maybe the 9.3x64. Keeps ones wheels turning.
Skimbleshanks
Well-Known Member
What weight range on the bullet and twist rate required?
74sharps
Well-Known Member
Mostly from 230 gr to 300 gr. and most 9.3s have a 1 in 14 twist.
The 9.3x64. And the rpm. The only difference. Is the. Case head dimensions. Be a great way to revive the bernekke
25WSM
Well-Known Member
So the 257 would be about 4 grains less powder capacity? But 6 more if the body taper was reduced?
Shep
Shep
74sharps
Well-Known Member
The RPM necked up to 9.3 would be almost identical to the 9.3x66 Sako, aka 370 Sako Magnum. According to what information I can get the Sako holds about 82 gr of water and the Brenneke holds about 88 gr of water.
Calvin45
Well-Known Member
Woah. Didn't realize the powder column was that much longer on the rpm than the belted case.
Those of you who want to create their own wildcat off the 6.5 WBY RPM parent case but are unsure of what neck diameter to use in the chamber, here is some helpful info on external neck diameters with bullet seated in a straight necked up case,
note that ... as case necks are necked up to larger diameters, brass thinning is normal and to prevent sloppy chambers, these measurements will help you in determining proper clearance with loaded rounds for your custom chamber/reamer
I normally use .004" over loaded round dims in my wildcats developed for hunting use ......
for example ...
my 358 RIPM has a .382" external neck diameter with bullet seated, on a straight necked up 6.5 RPM case to 358 caliber, my reamer will cut .386" in the chamber to allow bullet clearance of .004" (.002" per side in chamber) for proper bullet release and to prevent high pressure spikes from too tight of a fit with max loads ..
some of you more experienced wildcatters & shooters may want a tighter necked chamber in order to neck turn your brass for precision shooting/competition use, these dims will also help you in determining what you want in your reamer design ...
but be advised that brass thinning in the neck occurs as you go up in diameter from .264" of the parent brass, you may not want to turn off too much material in the larger diameter thinner necks
my apologies to those interested in .243, .270 and .366 calibers, I did not have bullets on hand to seat and create a sample/dummy cartridge
.....
note that ... as case necks are necked up to larger diameters, brass thinning is normal and to prevent sloppy chambers, these measurements will help you in determining proper clearance with loaded rounds for your custom chamber/reamer
I normally use .004" over loaded round dims in my wildcats developed for hunting use ......
for example ...
my 358 RIPM has a .382" external neck diameter with bullet seated, on a straight necked up 6.5 RPM case to 358 caliber, my reamer will cut .386" in the chamber to allow bullet clearance of .004" (.002" per side in chamber) for proper bullet release and to prevent high pressure spikes from too tight of a fit with max loads ..
some of you more experienced wildcatters & shooters may want a tighter necked chamber in order to neck turn your brass for precision shooting/competition use, these dims will also help you in determining what you want in your reamer design ...
but be advised that brass thinning in the neck occurs as you go up in diameter from .264" of the parent brass, you may not want to turn off too much material in the larger diameter thinner necks
my apologies to those interested in .243, .270 and .366 calibers, I did not have bullets on hand to seat and create a sample/dummy cartridge
.....
Calvin45
Well-Known Member
Honest question here...would a .458" work? I know it'd be awful close to straight wall which combined with a rebated rim sounds straight up unreliable but I ran the numbers on neck thickness and assuming the same neck thickness as your 416 creation it gives us .480" on a case that can be blown straight to .500". Can a meaningful shoulder or ghost shoulder be made from .02" (about half a millimeter?)
