The action that you're referring to that blew up might likely have blown up even if it was forged. The owner used 5744 and put a wad down against the powder to hold the powder back against the primer. At the least that will cause a bulged chamber, and if the load was a little heavier, or accidental over charged, then that's the result. Don't blame the gun for poor loading practices.
Smokeless powder is almost all I've used in over 3 dozen Ballard rifles I own. The only BP loads I shoot are when matches require me to shoot BP to compete. My loads are all under 20,000 psi and safe for old actions of any kind. I don't push my Ballard or other single shot loads, and I stick with cast bullets for all my shooting, whether the barrels are original, or rebarreled rifles. Just my personal choice.
