I have a CPA in 40/60 Maynard that shoots a BACO 420 gr tapered Money Bullet quite well using 60 gr of 2F in fixed ammo.  I was curious if using the same amount of powder and breech seating  the bullet it may even shoot a little better.
My question is this, if I put 60 gr of 2F in the case and a .060" veg wad in the mouth of the case, ( not down on top of the powder ) will this cause a problem  ie, chamber ringing.
I have tried the bullet breech seated with a full case of powder, 71 gr and it wasn't any better than the fixed load, although it went about 130 fps faster.
All my shooting is done either at 100 or 200 meters.
mike.

My only suggestion is to go to FG powder, Rem 2 1/2 primer and a 1/16" poly wad with a little  compression. If your willing to duplex, I would add 6 - 8 gr 4759 and cut the BP to a level load, still compressed.

Frank

mick,
have you experimented with the aigap length when breech seating using a full case?
40 cal might need 1/8" or thereabouts.
keep safe,
bruce.

Must have got 'em from breathing in the smoke.

The air gap thing is made on the 'net into something absolute - it never was.  FWIW, I shoot period military rifles in 577-450 with the powder level (yes, black) tot the bottom of the shoulder, with bullet, wads and lube cookie in the neck.  So yes, considerable air gap.  Shot thousands of rounds like that in different rifles, still waiting for that rung chamber...  And that's with older, softer steel barrels.
W.W. Greener actually advocated using partial loads in express rifles when the correct granulation wasn't available - he considered using too fine a powder more dangerous than shooting with an air gap.  I prefer to believe Greener instead of anonymous internet lore that is repeated like a mantra...

Mick, we smokeless shooters, secure in our ways, will always be missionaries to the unwashed, ill-educated blow tubers. Don't forget to drop yer empty cases into a bucket of swill- your grandkid's diaper bucket will do.
On a serious note, I hope you get the thing to shoot well, and safely.

If you have to wipe between shots, you should change your diet. Blow tubing might be worse. 

Mike B, you sound like a man after my own heart.  I have an original No.2 Ballard in .25-25 Stevens.  Since this is a cast action, I am only using Swiss 3FG.  I have tried reduced charges..and used COW to fill excess space...bad move!  These cases are turned from solid (RMC Co.).  The slight striations from machining inside neck must have grabbed the COW & stretched cases..causing one to seperate.  I have since resorted to Puff-Lon fiber filler with no problems and excellent results.  This has all been with fixed ammo.  I do plan on trying B.S. in future.