I had Kangaroo burgers once, at an Radio Control aeroplane pattern flying contest - the burgers were just fine - good actually and just barely, almost cooked through - everyone liked them.

.222 ctg. length is 1.70", .223 is 1.76" and the .222 mag is 1.85".

Here, in around 1970, the 6mm X .222 came out as the 6x45mm, a wildcat Sporter round. As I understand it, the sporter bore size had to be .240" minimum, which already eliminated the .234's that Ackley had been working on in the 50's and 60's and it also to have a case capacity of a .222 or greater - something like that.

McCracken custom bullets were quite popular with the 6x45 shooters here in B.C. The 70gr. McCrackens were extreemly accurate in my 6mm Rem. with 38.0gr. 3031 - amazingly so, with consistant 5 shot groups like the blackened hole in this target of Neale's. Nosler match bullets on the other had make .5" groups with the fouling shots - 1st of 6 always on the same bull. The consistancy of the fouler, was amazing - I used a 6 bull target so the top left was always the fouling target & I could shoot 5 bull aggs on the single page target.