I believe the Walkers had a larger
Cylinder capacity and were being
“Overcharged”.
Thanks Swordmaker.
That was the exact problem with the original Walkers and why there are so few surviving examples of what should have been a robust gun. Iffy steel content (too much carbon, not enough iron in old steel) resulted in catastrophic failures if the cylinder was overloaded with black powder and then a ball was crammed in compressing the powder. The recommended load was essentially the same as for the later 1860 Army Colt: 35 grains max. Some were cramming up to 60 grains in the Walker merely because the cylinder would hold that much. Modern Walkers with modern steel can handle up to 50 grains of black powder safely. I would still not use 60 grains due to the likelyhood of cross cylinder discharges which is far more likely when the cylinders are overloaded.