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Sir John,

Your choice of COL will be interesting.
I have not tried any 3.340" COL loads with that bullet.
Starting at about 70.0 grains of AA-2230 with COL of 3.340" would be most interesting.
My Long COL results:

Norma brass, F215 primer, 3.565" COL, 450-gr TSX, 3-shot averages starting with 80.0 grains AA-2230
in a Ruger No. 1 factory barrel, 24", 82*F, corrected to MV for BC = 0.369:

80.0 grains AA-2230 >>> 2408 fps MV (second most accurate load)

84.0 grains AA-2230 >>> 2464 fps MV (Most Accurate Load, a 50-yard bugholer)

85 and 86 grains gave less velocity, and only one shot with 86 grains was fired because the primer fell out of case on ejection.



Hornady brass, GM215M primer, 3.680" COL, 450-gr TSX,
in a Shilen 25" barrel on a CZ 550 Magnum, 42*F:

80.0 grains AA-2230 >>> 2407 fps MV

82.0 grains AA-2230 >>> 2448 fps MV (Most Accurate Load, 50-yard bugholer)

84.0 grains AA-2230 >>> 2469 fps MV (scope loose after 36 rounds fired, this bullet and 350-gr TSX also being tested same day)


WW-Super brass, F215 primer, 3.570" COL, 450-gr TSX,
in same Ruger No. 1 factory barrel as above, 24", 80*F, LabRadar MV, average for 5 shots:

83.0 grains AA-2460 >>> 2459 fps MV (best 3 of 5 hasty shots landing at 100 yards were about 0.5 MOA on centers)

Lessons learned:

1. Check ring screws after every 20 rounds, at least, with kickers,
and silicone adhesive between scope and lower ring half (at least) is a good idea to prevent loosening.

2. Norma brass may be loaded to a COL of about 0.1" shorter than Hornady or WW-Super brass
to make roughly equivalent loads.

3. AA-2230 and AA-2460 both seem to have good ThermoBallisticStability, they are close to the same composition.
AA-2230 is just AA-2460 with some flattened balls to make it pack easier and burn a little faster.

4. 83.0 grains of AA-2460 in Norma brass at 3.460" COL might be ideal.

5. How much AA-2230 can be burned behind a 450-gr TSX at 3.340" COL in Norma brass with satisfactory results
is unknown to me, but needs to be discovered.