Grant,
Thanks, suppose I was being a bit cheeky in asking the question, but rarely do you ever get feedback from articles, you just don't know if works or not.

My 450 is nice to shoot, I've only ever shot it with the blackpowder loads, as I have a 450 Ackley, 416 Taylor and a 416 Ruger for Group 2.
I wanted it to have the slightly "English Stalking Rifle" look to it (on a budget) so went with the longest barrel we could off the shelf, and a lighter profile. Ended up being very nicely balanced.
I've now gone to AR 2207 as the priming powder and a 300 grain cast bullet (a bit closer to the original bullet weight) and it seems to be performing better than ever.

The only other modification I had done, which seems to be commonplace, is to have the top edge of the safety filed back a little, to let the empty case clear the action better.

Ben, Thanks for the kind words, sorry I missed catching up with you a few weeks ago, work got in the way! Would have been a little wet around the place as well. I'll be back up in June sometime.

Regards,
David.