Many black powder shooters indicate they want to over spin their bullets (Sg>2.0) to compensate for drag when shooting long distances (1,000 yards).
They do so by choosing a tighter twist barrel.

Dave Gullo has demonstrated excellent performance shooting long range so I decided to evaluate if he was over spinning his bullet.

Caliber      0.447      Inches            
Bullet Weight      525      Grains            
Bullet Length      1.45      Inches            
Barrel Twist      17      Inches/turn            
muzzle velocity      1350      fps            
Temperature      50      degrees Fahrenheit (59 is standard)            
Pressure      29.92      inches of mercury (29.92 is standard)            
                       
Sg =      2.51                  
           
                       
Sg shouldn't be less than 1.4 (not spinning fast enough).  If Sg is greater than about 2.0 you may affect accuracy. 

Dave Gullo is over spinning his bullet in his 17:1 twist barrel but has enough velocity to stabilize the yaw. 

His Creedmoor nosed bullet has the center of gravity far enough forward providing good dynamic stability at long range.

(This has been edited since I found his bullet was actually a bit shorter)
     
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So the next question is: When does overspinning of the bullet become excessive and the low velocity of BP shooting mean you will no longer be able to stabilize the yaw? 
In other words when is the rifling twist too tight?
                 

Dave Gullo's rifle is a rebuilt antique Ballard Number 7 A-1 Extra Long Range action, rebarreled and chambered for the .44-90 Remington Straight cartridge. His load featured bullets from a BACO Creedmoor nose mould (JIM447525C2) at .447-inch diameter, weighing 525 grains when cast from 20:1 alloy and powered by 74 grains of Swiss 1½ Fg. Other ingredients for his loads included a .030-inch poly wad, Federal’s GM210M primer and SPG Tropical bullet lube. The .44-caliber barrel, which was made by Krieger has a 1:17-inch twist. A Kelley Soule tang sight is on the rifle and at the front rides an MVA #118 sight with a .105-inch aperture.

When I tried the Money bullets (with center of gravity further back than a Creedmoor) I found it went to sleep at 500 yards.

In other words the velocity we normally shoot BP at would not stabilize the yaw which becomes worse with increased drag over time over longer distances travelled.

To get the Money bullet to shoot I went to Swiss FFFg which provided the velocity I needed to stabilize my Money bullet which has more yaw because of it's center of gravity.

But my Paul Jones Creedmoor bullet which I used in a different rifle shot long distances at lower velocities without going to sleep.
The PJ bullet had the center of gravity further forward due to the nose design, but was also further ahead than other makers of Creedmoor nose bullets since he cut the grease grooves deeper and wider to remove weight at the back.

I've had much better results with weight forward bullets for years, and try to choose that design whenever I'm picking a mold for any new cartridge I begin loading for. 
I've contemplated trying to have a mold built with not only deeper lube grooves, but also a hollow base, just to see if lightening the tail of the bullet even more will increase stability more too. Of course it would be a nose pour also, to be able to have a good hollow base design bullet.

Interestingly not all of the BACO money bullets seem to have the same nose shape.  My 458535M1 has a pointier nose than my 459540M3 & 459542M3.   

Those 3 all seem to work well for me, although I always wondered why BACO changed the nose shape.

Chris.

It is possible for sure Dave, but there sure are a lot of guys finishing in the top 3 shooting 45's with 1:16 twist and Money bullets.  That's why I switched to that setup and I am super happy with it.  Of course long range BP shooting is tricky because there is always so much going on in 3+ seconds of bullet flight through variable winds, that it's difficult to tell whether a perceived small improvement is real or not

Chris.

maybe 72 cal mini balls are the answer

Decades ago I also switched to tighter twists and heavier bullets in the Schuetzen game while increasing my powder load and it improved my scores.

The heavier bullets with better kinetic energy due to their mass and velocity were far less susceptible to wind drift.

So many long range shooters think they are reducing bullet drag by using tighter twists where I say the benefits come from using heavier bullets at more velocity resulting in improved kinetic energy.

I am not sure the improved BC of a Money bullet nose is that beneficial compared to using a slightly heavier Creedmoor bullet with better dynamic stability (due to forward center of gravity) and greater kinetic energy.

Dave Gullo has been extremely successful using Creedmoor bullets.

And yes I would prefer a 69 cal. miniball (750 grains) sniper rifle instead of a 58 cal. (500 grains) but would not want to be hit by either.