Thoughts on which hunting cartridge

Like most men I am a bit equipment-obsessed and I have been doing a fair amount of research on this subject. Summarising this will likely take more than one post, but here goes:

1) What are my hunting parameters?

I am likely to hunt in two jurisdictions, Sweden and Ireland. Sweden demands at least a 9g bullet with 2,700J for mammals bigger than roe deer. Ireland allows anything from the 22-250 upwards to be used on mammals bigger than a hare. Ireland also has an inofficial legal limit of .30 as a maximum calibre. Now usually that would not be a problem. But: I have been seriously convinced by the modern breed of non-lead bullets like KJG, Impala and Jaguar. Especially KJG seems to make a lot of sense and those bullets are light! The smalles calibre a 9g one is offered in is 8mm. So this will make getting a 'rifle of all trades' which basically KJG seems to make possible if one doesn't shoot into bone, ie. the shoulder, but behind it. But 8mm is bigger than expected in Ireland and might need more arguing than I am capable of.

OTOH if I can argue it I would like a rifle in 8x64 S, which is an old German cartridge invented by Brenneke between the wars. I shoots a bit flatter than the 8x57 IS without being such a magnum monster as the 8x68 S. With the 9 g KJG and a reasonably hot load I could get it to shoot like this (data out of QuickTarget):

Optimum trajectory information :
Optimum sight-in range (X) = 213 m
with max. ordinate above LOS at range (M)= 125 m
and max. point blank range (P)= 248 m.
-------------------------------------------------------------------------------------
Sight-in clicks, 1 click = 1.0 cm/100 m or 0.394 in/100 m
Height of sight above bore axis = 3.61 cm or 1.421 inch
Gun is zeroed-in at 210 m,
by sighting-in at level firing

Range(m)	V(m/s)	Energy(J)	Path to LOS(cm)	Drop (cm)	Elev (MOA)
0	1000	4509	-3.6	0.0	4.6
25	981	4335	-0.6	-0.3	5.4
50	962	4166	1.8	-1.3	3.4
75	943	4003	3.5	-2.9	3.0
100	924	3846	4.5	-5.2	3.0
125	906	3694	4.8	-8.2	3.2
150	887	3547	4.4	-11.9	3.6
175	869	3406	3.1	-16.5	3.9
200	852	3268	1.1	-21.9	4.4
225	834	3136	-1.9	-28.1	4.8
250	817	3007	-5.7	-35.2	5.3
275	799	2878	-10.4	-43.2	5.9
300	780	2742	-16.0	-52.2	6.4
325	761	2611	-22.5	-62.0	6.9
350	743	2484	-30.1	-72.9	7.5
375	724	2363	-38.9	-85.0	8.1
400	706	2246	-48.9	-98.4	8.8

M = Peak vs. L.O.S, X = Set Zero, P = Max. Point Blank Range
Elevation above Angle of Site (0.0 deg.) = 0.0760 deg.

I think that should do and if I ever want to shoot a bit further that is what ballistic tables are for.

OTOH if I end up not getting a permit for this calibre for Ireland I will need either 2 rifles or 2 barrels for the same rifle (saves money in scopes if nothing else). In that case I may well give in to the temptation to get magnums: .270 WSM for Ireland and .338 WM for Sweden. But it would be silly.

And the nice thing about the KJG is that I can basically shoot the same cartridge, load and rifle on anything between hare and elk/moose.