Which barrel?

[.300 Dakota]

I put together an 8 X 57 with Rock Creek number 3 contour. I believe its a 1 in 9 twist with a 24 inch length. It was built on a 98 Mauser . The Rock Creek barrel is very accurate and it provides some very high velocities, at least when compared to what Quickload estimates. The gun shoots the 170 grain Hornady SST and Nolser Custom Competition 200 grain and Hornady 196 Match bullets very well. The later two have BC 's at .520 and .525 respectively. I also have some old Norma 197.5 gr BTHP hunting bullets which will also shoot less than one moa. I am getting 2690-2700 fps with the match bullets with CF-223, and that is max. They do their best accuracy around 2640-2650 fps. The 170 Hornady will do 2800 and I have taken whitetails with that. Nothing over 200 yds but the 170 gr SST will hold together when woods hunting at less than 50 yds. All complete pass throughs. We need more 8mm LR bullets, but the demand is too low.

Man, I had no idea Rock Creek made 8mm. Actually, I don't know how to get my hands on one of their barrels. Other than PVA, there's nobody that I know that sells them. Southern Precision use to, but haven't had any in stock in eons. They had stopped selling direct to public at one time, but maybe that's where to look?

 

[.300 Dakota]

Brux or Mullerworks.

Neither make a .323 caliber blank. Would have never posted this question if I could have gotten my hands on either one of those, that's FOR SURE! Art W has me intrigued about the possibility of Rock Creek. I'll have to see if I can get a response from them.

 

[simo hayha]

Let me guess 338 lm necked down to 8mm, pushing 270 grains of goodness....

 

[.300 Dakota]

Let me guess 338 lm necked down to 8mm, pushing 270 grains of goodness....

Lol, no, either .27 or .28 Nosler necked up. I prefer the .27 case, but need to see how thin the neck gets going .046". Should work. Nearly the same as going from .30 to .35 caliber. A stretch. And no, I was limiting the bullet selection to the standard 220 grains with a standard 10 twist. The .28 has a little more juice, but the neck is very short for an 8mm cartridge. Yes the .30 would be a sensible solution, but I don't have as much onhand and still favor the .27. I'm trying to ensure it stays in a standard long action. The whole deal was to best the 8mm Rem Mag and be capable of fitting a standard long action.

 

[.300 Dakota]

I have both types of brass onhand and many 8mm bullets just staring at me.

 

[RockyMtnMT]

Lol, no, either .27 or .28 Nosler necked up. I prefer the .27 case, but need to see how thin the neck gets going .046". Should work. Nearly the same as going from .30 to .35 caliber. A stretch. And no, I was limiting the bullet selection to the standard 220 grains with a standard 10 twist. The .28 has a little more juice, but the neck is very short for an 8mm cartridge. Yes the .30 would be a sensible solution, but I don't have as much onhand and still favor the .27. I'm trying to ensure it stays in a standard long action. The whole deal was to best the 8mm Rem Mag and be capable of fitting a standard long action.

I recently did a 36-30 Nosler. Haven't got to shoot it much yet. It got put on the back burner when we couldn't take rifles to Aussie. I like your idea of using the Nosler case for 8mm. The reamer we used was not ours and was designed in between 28n and 30n. I wound up using 30n brass but had to deal with pushing the shoulder out on fire forming. Other option was to run the reamer deeper to accept the 28n brass but felt the neck up was too far. Good luck on your rifle. I think it is going to be a great cartridge.

 

[.300 Dakota]

That sounds like a formidable round, indeed. Quite a jump from the 9.3x62 (or even the 9.3x64). Sounds like an excellent water buffalo round!

I toyed with the idea of a .358/.33 Nosler, but performance wouldn't be significantly better than the .358 STA. What it would do is readily fit into a standard length magazine and allow the loader to find brass occasionally that would take less work on the brass to form.

That .27 Nosler case is really appealing to me. I would go as far as making a 7mm/.27 Nosler and sacrificing a couple grains of barrel-burning capacity from the .28 for a neck ample long to comfortably hold even the longest 7mm pills.

But yes, the 8mm way under appreciated in the States. I found the combintion of the .325 WSM and Norma 203B powder with 200 grain Speer Hot Cors to be an astonishing combination yielding well in excess of 4000 ft-lbs of energy from a 23" Browning X-Bolt barrel. Nothing else came close! I'm longing for the day when Woodleigh Weldcores come back to market! I wouldn't burn 203B in a Nosler-based 8mm, but I could certainly use MRP! (I also long for the day when Norma powders are available again.)

I have several 8mm bullet varieties onhand, and would like to find a platform to launch them from that would be worthy of their potential. Perhaps I can decide on a barreled action and stock combination to give it a go!

Your .36/.30 Nosler gives me assurance that I can indeed reliably expand the .277 neck to .323. I would be using Peterson brass instead of Nosler or ADG. I know Peterson makes good brass, but I don't know about its properties that govern expansion and stretching of brass. Presumably, any brass that is sufficiently annealed would be suitable. I do know that Peterson brass is annealed.

 

[RockyMtnMT]

That sounds like a formidable round, indeed. Quite a jump from the 9.3x62 (or even the 9.3x64). Sounds like an excellent water buffalo round!

I toyed with the idea of a .358/.33 Nosler, but performance wouldn't be significantly better than the .358 STA. What it would do is readily fit into a standard length magazine and allow the loader to find brass occasionally that would take less work on the brass to form.

That .27 Nosler case is really appealing to me. I would go as far as making a 7mm/.27 Nosler and sacrificing a couple grains of barrel-burning capacity from the .28 for a neck ample long to comfortably hold even the longest 7mm pills.

But yes, the 8mm way under appreciated in the States. I found the combintion of the .325 WSM and Norma 203B powder with 200 grain Speer Hot Cors to be an astonishing combination yielding well in excess of 4000 ft-lbs of energy from a 23" Browning X-Bolt barrel. Nothing else came close! I'm longing for the day when Woodleigh Weldcores come back to market! I wouldn't burn 203B in a Nosler-based 8mm, but I could certainly use MRP! (I also long for the day when Norma powders are available again.)

I have several 8mm bullet varieties onhand, and would like to find a platform to launch them from that would be worthy of their potential. Perhaps I can decide on a barreled action and stock combination to give it a go!

Your .36/.30 Nosler gives me assurance that I can indeed reliably expand the .277 neck to .323. I would be using Peterson brass instead of Nosler or ADG. I know Peterson makes good brass, but I don't know about its properties that govern expansion and stretching of brass. Presumably, any brass that is sufficiently annealed would be suitable. I do know that Peterson brass is annealed.

I took the 30n Peterson brass to .366" in three steps. Then fire formed with bullets jammed in the lands.

 

[.300 Dakota]

So is Rock Creek still in business? Their Web site still says not taking orders - same as it's said for at least the past couple of years. It lists 3 stocking dealers, 1 being Southern Precision Rifles who have not had a Rock Creek in stock in nearly 2 years, I'd say. Another is in Canada, and another being a gunshop in Utah. I searched the link for the shop in Utah and could not locate a Web site.