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Hello from Scotland~

The .308 would seem extremely efficent case like wise .243/.260./7mm-08/.338-08/.358 can be packaged in small light weight short action.
The wildcats all are very eficent and can Nearly match velocities of much larger cartidge cases for a significant reduction in powder.

Can I ask what there is in the way of .22 and .257 wildcats based on the .308 ?? Surly both calibres are natural candidates ?????

Regards Englander
 

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I've got some info on a 270/308, nothing on the 25/308 though. If you are interested in the 270 version here goes:

Platform was a Browning BLR with a 24" Douglas Premium barrel. Dies made by RCBS. New 308 brass was used and necked down by one pass through the RCBS 270-308 sizing die then trimmed to 2.020 inches.

The author (Jack Huber) used 4 different 130 grain bullets.

Sierra boattail most accurate load was with 46 grains of 4350 with a muzzle velocity of 3,041 fps and 0.25" groups.
47 grains of 4350 gave muzzle velocity of 3,072 fps and 0.50" groups.

130 grain Speer Spitzer best load was also 46 grains of 4350 with a muzzle velocity of 2942 fps and 1.00" groups.

130 Hornady was the same 46 grain load of 4350 for 3,012 fps and 0.50" groups.

130 Nosler solid base mirrored that 46 grain 4350 load with 3016 fps and 0.40" groups.
 

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Hi, Englander:
Almost every wildcat possibility is out there and your two are no exception. Both are listed in the 1997 RCBS Special Order catalogue. A look at the catalogue shows that there's a die popularity rank of 1 to 5 based on price and shiipping time, with a 1 being very popular (.30-06) and a 5 not (.22-303 British Improved AND .22-308:eek: ). Since a .22-308 has little more case capacity than the .220 Swift and probably not as much as the .22-250 Improved 40° (ranked 3), it's not selling.

The .25-308 or .25 Souper is in the unfortunate postition of having a half grain less case capacity than the standard .257 Roberts, although it ranks at 4. The real wildcatters use a .257 Roberts Improved 40°, based on it's rank of 2. These case capacities were interpolated form the chart in Handloader's Digest.
 

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The .22 CHeetah is based on a .308 case with a small rifle prime. I have a friend who uses his for coyotes and it beats the .220 Swift hands-down, and his shoots very, very accurately. If used on a dog town, it would fry the barrel, but on coyotes with slower shooting his barrel has lasted for several thousand rounds.
Willie
 

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I guess there is also a 257 DRG that is based on the 308 case. I don't know anything else about it though. I'm sure RCBS could help out with the specs.
 

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I've always wanted to neck up a .243 to .257 to cover bullet weights from 60 to 120 grains. This should beat the 250/3000 Ackley by 100 fps with the 120 grainers, or 2920 fps or so. This is easier to make than the Ackley, which must be fireformed and would be better than the 243 for deer while giving up nothing for varmints.
 

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The Hog Whisperer (Administrator)
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.25-308 would pretty well duplicate the .257 Roberts, which is probably why there is no commercial version of the same.

.270-308 sounds kind of interesting.
 

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This is off topic slightly but I believe that their was a 270 wildcat based on the 300 savage. I suspect that it and the 308 based cartridge would nearly identical in terms of preformance though the 308 would probably be better in the real world due to the longer neck. The 257 wildcat interests me more personally, espicially in a BLR or Savage 99. Would a 308 based 257 feed properly in a rotary action Savage? If so a 250/3000 could be easily upgraded to 250/308.
 

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7mm,
You have a personal message.
 

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I just completed a 270-08 AI 40 degree. I didn't have alot of time to work with it before deer season here, but I'll post what I've worked up so far. I built it on a Mod. 70 action with a Shilen 1:12 twist - 22" lightweight barrel. The bedding/stock was reworked for the slightly different contour. The rear guard screw was torqued to 25 in/lb and the front to 45 in/lb. Virgin Winchester 308 brass was necked down and fireformed with 130 SST - 46.0 - H-4350. The cases were then neck sized using a CH4D floating sizer. Federal 210 primers were used.
Powders in the 4350( both H and IMR) range seemed to be somewhat on the quick side for it. R-22 finally gave the best accuracy using 49.5 grains. Velocity averaged 3160 fps and the best group to date was .360". Most groups averaged in the mid to low 4's.
When it warms up here a little, I'm going to work with R-22 to see if it will exceed 3200 and still maintain the accuracy. I'm also going to rebed it using Pro Bed 2000 and play with the torque to see if I can keep in under .5" with the higher velocity loads.

If anyone is interested, I'll post what I work up.

Bill
 
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