Over at least the last 40 years, I have tested many boxes of original factory BP loads. Unless stored in poor conditions, BP does not deteriorate. It is important to note that almost all the ammunition functioned perfectly. I did comparisons of 32 Long & Short RF when Navy Arms first came out with smokeless loads for this caliber. Velocity and felt recoil were easy to compare. I even came up with a spring loaded support for quantitively test recoil. One can measure the amount of muzzle jump when the gun was fired. Navy arms came out with a notably safer load than factory BP. Velocities were lower, 650fps for UMC BP vs 550fps Navy Arms Smokeless. Felt recoil for Navy Arms ammo was easily less. Muzzle jump for Navy Arms ammo was half that of UMC and Winchester BP loads. I have done similar comparisons to just about every BP era caliber I have owned with the same results. Factory smokeless offers lower pressures than every BP round I have tested.
If you do a search of the Forum, I have posted several studies and research papers on this subject in the past, all resulting in the same two things. Authors proved that smokeless can and is loaded to offer exact performance and same or lower pressures than original BP. That fact cannot be debated if one takes the time to pull up and study these published results. In 1909, Smith & Wesson printed a statement in their catalog related to this subject. Over 100 years ago, the company accepted the fact that factory smokeless ammunition can and was loaded to be absolutely safe in their top-break guns. In the infancy of reloading, back when people knew little about the proper use of smokeless powder, they ended up destroying lots of guns by filling the case with that powder as they did with BP. The results were catastrophic. Powder companies did not help the issue much since they produced bulky smokeless (loaded by volume as BP) and nitrocellulose powders (loaded by weight) at the same time. 14 broken antique guns in Don's collection could have been destroyed by the improper use of these powders, plugged barrels, barrels with stuck bullets, half loads of BP, etc. I have also seen dozens of modern revolvers that have been blown up, but all are of no value unless each and every instance of destruction was known.
I am not a member of the "smokeless club", but see you constantly come up with terms meant to demean a group of members who have undoubtedly done more research on the subject than you. I am amazed that the guy who seems to own the Antique Section gives no factual information to support his position. Maybe because there is none? I hesitate to continue to add objective studies on the topic, since I am certain it will make no difference in your position, but will leave you with just a fraction of available information. First, the recent article on this subject is quick and to the point. I have another dozen of these that offer the same results including some gun powder companies graphs and charts from the very early days of smokeless. This test compared BP to smokeless loads using various powders in rifle barrels. These results can be compared in revolver barrels, but pressures will be lower due to the amount of time the bullet remains in the barrel. Full article should be available through the Sixguns Firearms Fraternity.
Second, Sherman Bell did exhaustive testing on Damascus/twist shotgun barrels and found it is possible to mirror original BP burn rates and pressures with smokeless powder. Double Gun Journal article can be boiled down to fes graphs that debunk any differences in pressure spike duration in the barrel. Bottom line of Sherman's study is that you can mirror BP load characteristics with smokeless powder!
Lastly, steel was invented in 1850 and by 1879, ultimate tensile strengths were 64,000psi. Safe working strengths at that time were considered 25% of ultimate strengths, or 16,000psi. We are normally talking about needed working strengths in the neighborhood of 10,000psi to 14,000psi. Plenty adequate strength for building guns of the era.
