I recently picked up a BT60-sized ramjet type nose cone from Semroc and had t' decide what t' do with it.  I already built an upscale Teros, and I didn't really feel like doin' a Strike Fighter at this time.  So, me hearties, I decided t' upscale t' Battle Star Galactica Laser Torpedo.  I'm nay actually a BSG fan (have yet t' see an episode), but t' rocket is a neat design - sort o' a variant o' t' original Photon Disruptor. 

So, that's what I did.  T' original model was essentially minimum diameter in its lower section containin' t' motor mount.  When upscalin' t' upper section from BT50 t' BT60, t' lower tube roughly scales from BT20 t' 1.25" in diameter.  I could make it BT55, but t' proportion would be off.  And I wanted t' retain t' original layout o' min. diameter, with exposed retainer hook and sleeve.  So, I made t' lower tube 29mm, which has an OD that is slightly smaller than true scale.  ASP sells retainer hooks long enough for t' Estes 29mm BP motors, so that's what I designed it use. 

T' only 29mm t' BT60 centerin' rings I could find are fiber, me hearties, so I used two on each end o' t' tube joint, basically doublin' them up.  T' main fins are basswood, whereas t' strake fins are hard balsa.  And t' engine hook sleeve came from Estes - its t' spacer rin' that comes with PSII kits, used for placin' t' centerin' rings correctly on t' motor mount. 

With 29mm power, this will likely be very quick off t' pad.  T' BP motors will yield impressive performance themselves, matey, but with a composite motor I expect that it'll near teleport.  I may have t' invest in a tracker for this one.  Accordin' t' t' sim, anythin' in t' "G" impulse range is enough t' break mach - which it isn't built t' handle - so I'll have t' cap it with a moderate "F"...