Sherman Bell did that with various BP cartridges
and wrote up the results in the Double Gun Journal. Lots of interesting info; one item was the effect different types of filler had on pressure in both NFB loads and BP loads.
Complete thread:
- 12mm pinfire - 
A K Church, 
2024-03-10, 09:16 
- 12mm pinfire - 
Slow Hand, 
2024-03-11, 08:18
- 12mm pinfire - A K Church, 2024-03-11, 09:49
 - Sherman Bell did that with various BP cartridges - 
JohnKDM, 
2024-03-11, 17:04
- Sherman Bell did that with various BP cartridges - 
Slow Hand, 
2024-03-12, 10:16
- Have not seen him.  I do shoot a lot of duplex loads - 
JohnKDM, 
2024-03-12, 12:38
- Have not seen him. I do shoot a lot of duplex loads - A K Church, 2024-03-12, 18:14
 - Have not seen him. I do shoot a lot of duplex loads - Slow Hand, 2024-03-12, 18:24
 
 
 - Have not seen him.  I do shoot a lot of duplex loads - 
JohnKDM, 
2024-03-12, 12:38
 
 - Sherman Bell did that with various BP cartridges - 
Slow Hand, 
2024-03-12, 10:16
 
 
 - 12mm pinfire - 
Slow Hand, 
2024-03-11, 08:18