Mr. Ackley did a 2 volume set of books back in the 1980s that cover thousands of cartridges... factory, Improved, and wildcat... Available from eabco.com, sinclair International, ebay sometimes, etc... I read to relax... (More reading than shooting, darn...)
Way back when-- (WW I) H&H had a .244 H&H... Tapered case like .300 H&H to 6mm. NO barrel life at all. (surprise, surprise...) And from the H&H belted case was born... -???- (get the books and look for yourself. Dozens...) All this was commercialized by Mr. Roy Weatherby, post WW II... I think you will find the .257 Weatherby mag is the .300 H&H Case, necked to .257 and blown out with the trademark radius shoulder angles... Or the .300 Weatherby, or .270 Weatherby or 7mm Weatherby necked down... Developed in 1917 Enfield action I am told.
I found it interesting that even Mr. W did not see going to 6mm, but chose to use a belted case that duplicates the .30/'06 with the belt swaged on. (That is work...) as was done by Mr. A and others...
And, post WW II, the case was shortened to work thru the 03 Springfield action (Metric 7.62x63mm), available surplus CHEAP, (whole rifle, $18.00 or was it $18.50??? Walnut stock. REA would leave it on your porch. Drooooolllllll...). I think .308 Norma was "out front" here commercially. Old friend, gunsmith now retired told me of Norma renting a reamer suitable for re chambering '03s, cheap... .30/338 WCF wildcat uses same data... [CAREFULLY... !!] Remington copied the thinking in the 7 Rem mag... Win the .264 WCF Mag... .338, .458 actually...
His (the gunsmith's) preference, was the 6mm/.284. '06 powder capacity with the short powder column, sharp shoulder thinking of more modern design.
So yes, it has been done. Not known for long barrel life. P'dogs? NO! Cross-canyon deer? GREAT!. LUCK.
