Any one Know what this case is . ?? Is it a necked down 9.3x64 Brenneke case .???

No. The "64" in caliber designations such as 7x64 or 9.3x64 only denotes the (approximate) length of the case in milimeters. It says nothing about case head. So the 8x64S is essentially a necked-up 7x64, but has nothing to do with the 9.3x64 case (larger case head, larger case diameter).

You can make 8x64S brass by necking up 7x64 brass and fireform (although the result may be a tad on the short side). If you choose to go this route, it is probably advisable to make a fake shoulder in the neck-up to avoid excessive case stretch.

Much easier, however, is to obtain some of the fairly reasonable (price and quality wise) Sellier & Bellot factory brass. That will leave you with correct headstamps.

- mike

WHERE do I find S&B 9.3x64Brenn brass ... I had no idea they made it ..?????

I don't know if S&B make 9.3x64 cases, I don't think so, though. Availability of any such brass in North America seems to be a problem at the moment - at least if the discussions here are anything to go by. Some suggested a source in Canada - forget the name, custom gun supplier...

This place might offer 9.3x64 brass - don't know what kind, though:

http://www.buffaloarms.com/browse.cfm/4,821.html

When I talked about S&B brass in my reply above, I was referring to the S&B 8x64SS brass - just in case that is not clear?

- mike

quote:

Any one Know what this case is . ??

This round is essentially an 8mm/'06 with one millimeter more case length..... So you can make it from 30/'06 brass necked up.

Sounds like a chamber cast is in order.

8x64mm S maximum C.I.P. cartridge dimensions.
.
Case type Rimless, bottleneck
Bullet diameter 8.20 mm (0.323 in)
Neck diameter 8.96 mm (0.353 in)
Shoulder diameter 10.85 mm (0.427 in)
Base diameter 11.95 mm (0.470 in)
Rim diameter 12.00 mm (0.472 in)
Rim thickness 1.30 mm (0.051 in)
Case length 64.00 mm (2.520 in)
Overall length 87.50 mm (3.445 in)
Case capacity 4.51 cm³ (70 gr H2O)
Rifling twist 240 mm (1-9.449")
Primer type Large rifle
Maximum pressure 405 MPa (58,700 psi)

12.7 g (196 gr) S&B SPCE 810 m/s (2,700 ft/s) 4,166 J (3,073 ft·lbf)

12.7 g (196 gr) S&B HPC 815 m/s (2,670 ft/s) 4,218 J (3,111 ft·lbf)

12.8 g (198 gr) Brenneke TIG 841 m/s (2,760 ft/s) 4,537 J (3,346 ft·lbf)