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Posted: Fri Jun 03, 2011 6:42 pm
by GM
RDavies wrote:So, ballistic nonsense aside, you CAN easily get 2950 fps out of a Shehane, you just get case head expansion, loose primers, or have to use 168gn bullets or RL17 powder.
So if someone was starting from scratch, with no dies, cases, reamers or anything. What 7mm cartridge would the S.A shooters recommend for the windy conditions in the S.A ranges with a 308 bolt face? Are there any other European cases out there which are not yet fashionable, but could be formed into a big capacity 7mm?
Though not from SA perhaps the 7mm JAT. on the 9.3 x 62 case.
Posted: Fri Jun 03, 2011 8:29 pm
by bruce moulds
g m,
you remind me of a project i have on the backburner with your mention of the 9.3 calibre.
i have looked at pushing the shoulder of a 9.3x64 brenneke back about half way between where it is, and where a 284 is, with either a 30 or 35 degree shoulder.
the case has a similar diameter to the 284, so you would get a sort of super 284, or 284 express. the rim diameter could be left as is and the boltface altered, or could be turned down to be rebated a/la 284.
said case would have a longer neck than the 284, offering throat protection, and the ability to use long or short bullets in a short throat.
rws 9.3x64 brass has proven extremely consistent and strong.
actually, the 280 ackley would have about the same capacity, and tooling and brass would be cheaper.
bruce moulds.
Posted: Fri Jun 03, 2011 9:17 pm
by BATattack
a wise man once told me . . "crank it up untill it goes bang. .back it off half a turn and leave the f#$*&@ thing alone!!" thought he was a bit of a redneck but at the end of the day thats about what we do
7SAUM with a reabated casehead? problem solver'd
raven used to use a 7 rem mag. that has about the same capacity as the SAUM with much cheaper brass and dies.
anything with more capacity than that will toast barrels with no more performance even with the slowest powders.
if you want to stick to a standard boltface .280 or .280AI.
Posted: Fri Jun 03, 2011 10:23 pm
by bruce moulds
i did use a 7mm stw for a few shoots many years ago.
84 gn powder down a 7mm bore.
throat loss was visually obvious and easily measured each range shot.
bruce moulds.
Thanks
Posted: Mon Jun 06, 2011 9:22 pm
by MROFD
Thanks guys, I think some of it has soaked in.......
Certaintly has helped me make a part decision as to which path I will follow. I will keep you all informed as to how it all turns out, Hopefully soon I might even have some of my own opinons as to what works for me in a 7mm.
Either way, I appreciate all of your input and knowledge you have posted.
Cheers Matt
HELP .280??
Posted: Thu Jun 09, 2011 8:41 am
by MROFD
I had this responce from Dave Dibble (Redding) in response to chasing a Comp Die set for the 280AI.
Dave Dibble: I'm confused, the 280 Ackley Improved is now a SAAMI cartridge but the original wildcat (280 Remington Improved 40°) is based on the 280 Remington parent case.
We have another wildcat listed called the 7mm-06 Improved 40° that appears to be based on the 30-06 parent case.
So is the 280AI based on the 30-06Rem parent case?
If this is the story, should I be purchasing 7mm-06 I/40Deg Reamers and Die sets????
Matt
Posted: Thu Jun 09, 2011 9:48 am
by RAVEN
The 280Rem is Ackley improved usually by straightening the case sides and increasing shoulder angle hence 280AI
The 7X57 is also a good cartridge
http://www.reloadbench.com/cartridges/w285okh.html
285 OKH, 7mm-06 Mashburn, 7mm-06
Historical Notes:
These cartridges are lumped together because they are practically identical and, except for headspace specification, they are also very similar to the 280 Remington. The 285 OKH is another O'Neil-Keith-Hopkins development which originally used a duplex loading consisting of different powders with different burning rates loaded one on top of the other. It also employed a long flash tube that ignited the powder at the front of the case instead of the rear. This was supposed to improve ballistics and apparently did to a slight extent, but was a lot of trouble and rather impractical for the average reloader. All of these cartridges originated in the late 1940's and early 1950's.
General Comments:
Because these cartridges hold about 2 grains less powder than the 280 Remington, maximum 280 Remington loads are not recommended. The various 7mm's based on the 30-06 case are worthy of mention because they were the wildcat forerunners of the commercial 280.
Posted: Thu Jun 09, 2011 10:42 am
by MROFD
So let me try and get this straight,
I'm starting to think that the wildcat 7mm-06 Improved 40 (which uses a 30-06Rem necked to 7mm) which also has reamers & Dies available off shelf, would be a better option over the 280Ackley Improved SSAMI
Oogh my head hurts.....
Posted: Thu Jun 09, 2011 10:52 am
by RAVEN
Matt Y don't you call me and I will explain
Posted: Thu Jun 09, 2011 11:33 am
by AlanF
Before we recommend the 280AI, is there anyone who's got one that has shown its superiority over the other 7mms about. I can think of 6 shooters who've had or still have 280AIs but none that I know of are using them competitively in Queens shoots. Perhaps its one of those chamberings that looks good on paper, but is very hard to get going?
Alan
Posted: Thu Jun 09, 2011 12:54 pm
by ratshot
Matt 280 brass AOL is longer then 30/06. the best part of the 7/06 ack is you can use Lapua 30/06 brass but it has to be fire formed , where as Nosler are now making 280 ack brass it is dear and a bit soft from what im hearing.
Posted: Thu Jun 09, 2011 1:21 pm
by RAVEN
What is the case capacity betwen the 280AI & 7/06AI
Posted: Thu Jun 09, 2011 1:24 pm
by AlanF
Ratshot,
What chambering did you use at Canberra? I know you've used a 280AI in the past but had it in my (deteriorating) memory banks that you were using a SAUM there?
Alan
Posted: Thu Jun 09, 2011 5:32 pm
by Deano 29
Alan,
I scored Mr Ratshot at Canberra and I'm 99.9% sure it was am7mm Rsaum. I seen having to drag himself back up the mound ever time he pulled the trigger. He shot extremely well from what I recall.
Posted: Thu Jun 09, 2011 6:08 pm
by RAVEN
