the barrels arent especially designed as far as i am aware, as it will take a meteor or similar older springer barrel like a supersport. i dont think it will take a lightening, but i could be wrong? however, you may find that the barrels that came with 'em were choked for pcp - especially 177, but a standard older springer barrel probably wont be.
Spitfires rule! i picked up another one a little while back (i have a few now
) for £65!
If you can get JB to blueprint it, you'll be amazed by how good they can be once optimised - they are unique i would say
i would love to get my hands on a firebird!
is yours low fill or high fill?