What do you mean by "factory loaded powder"? Did you pull apart some old production cartridges? Or change the bullets in the BA rounds?
I'm glad to hear that it is shooting well for you. This caliber seems to get a bad reputation for accuracy. It certainly isn't a long range cartridge. But with a little load development it can hold its own within barrel sight range. I added an authentic Riflesmith tang sight to mine. It really helps with my aging eyes.
Yes we (I keep saying we, but it's really my friend doing all the work) pulled the bullets off the BA rounds and inspected the powder under magnification and it looked identical to 5744. So we loaded up 5 test rounds with 27gr of that powder and compared results with the known 5744. Shot pretty much identical.
We're feeling confident now that we can reclaim the powder so all we have to do is pull the bullets, remold the lead 51539 mould and re-assemble.
FWIW the 300gr and 350gr BA rounds both contain 33gr of powder but with yesterday's results we'll be loading up a bunch more with 27gr and down the road experiment with loads up to 33gr.
I originally bought 600 rounds from BA so we have plenty of reusable brass, powder, lead and primers.
ETA: Thanks again for your help in getting my 76 to be a real shooter.
Disclaimer: Just want to say the above info is working for my rifle and I'm not making any blanket recommendation for others.