Mizar
Member
CraigC revived my interest in damascus barreled shotguns and I started to read more and more about the subject. A mighty interesting issue I must admit! The tests performed by the guy from Double Gun Journal are really an eye opener.
Trailboss would be a good one to try if you were to experiment. It is loaded almost the same way black powder is loaded in cases. So again in theory. Trsilboss would act alot like smokeless as it is loaded to base of bullet for a max charge without a reference to case size, just like black powder.
because most smokeless loads are at less than 100% load density. try this with black powder and you will get the same kaboom in your bp gun. probably why bulk smokeless powders (like trail boss) work so well in the cowboy action game.Thanks again. I don't plan on ever using smokeless in a black powder gun, not even develop an equivalent load. I don't mind the cleaning up and BP is available here, so I have no reason to do it. I was just curious as to why for the same pressure, smokeless would be more dangerous, and a quick pressure spike does explain it. I have not reloaded BP cartridges yet, plenty of smokeless ones, but I have used lots of cap & ball replicas and still own a Pietta Remington 1858, using 35gr with a round ball, which has plenty of oomph! If all goes well I should be reloading .38-40 soon... That S&W looks great!
Gil.
Perhaps you missed what I said earlier. Trailboss absolutely is not a Black Powder substitute. And it absolutely is not loaded like Black Powder, all the way up to the base of the bullet! It is loaded just like any other Smokeless powder, with X amount of grains as dictated by the loading tables. How far that fills up the case will be determined by what the loading tables say for the Maximum load for that weight of bullet. Trailboss is much too fast a powder to be considered a Black Powder substitute, and it generates a very sharp pressure spike.
The rest of your post is unclear to me, but if you are advocating loading Smokeless power into a Cap & Ball revolver cylinder, that is a big mistake. There is a reason modern Black Powder revolvers are stamped "BLACK POWDER ONLY"!
DriftWood... You are 100% Correct.Trailboss absolutely is not a Black Powder substitute. And it absolutely is not loaded like Black Powder,
Howdy
The problem with a Damascus barrel is that over time corrosion can set in along the many feet of welds. The only way to know if a Damascus barrel is safe is to proof it again. If it does not blow up, it is safe..
Well if you read from the manufacturer recommended way of loading trailboss it is loaded exactly like I said. That is how they recommend loading it when data is not available for your cartridge. I am not advocating it in any way. I am pretty sure I included to say you don't have the testing equipment to try it and. Used the word theoretically a couple times. I suggest you look up some more info on trailboss. Before you make comments on how it's loaded without knowing.
Also all the max loads for trailboss seem to be at the base of the bullet for the several calibers so you might have no experience with this powder from your statement. I'm going to attach a picture of how hodgdons/imr tells you to load trailboss and it clearly states this is your max load at base of bullet.
Trail Boss was made as a powder to fill up black powder brass which has way more space than needed with smokeless powders. It was conceived as a way to prevent double charging as most smokeless powders when double charged in BP cartridge cases like 45 Colt and others don't overflow the case. Also some smokeless powders have a problem with a tiny bit of powder in a large capacity case and have erratic ignition. It has gained some popularity as reduced loads in some rifle cartridges like 30-06 and 7.62x54R for recoil sensitive shooters such as the young or inexperienced. It was never intended to be used as a black powder substitute or is it marketed as such..
Peak pressure in smokeless vs Pmax with BP is akin to comparing an apple to a similar-sized orange. The BP pressure application curve is significantly spread out under the peak -- akin to a push, rather than the closed-fist punch from a fast-burn smokeless propellant -- including/especially that of Trailbossthen you likely could use equal max pressure loads in a BP gun.
One of the weird things about light charges of smokeless powder is that they can sometimes exhibit pressure spikes that far exceed their normal performance....likely due to static charge spreading the powder all around the case which is then simultaneously lit by the primer vs the normal more progressive burning when the powder is stacked against the ignition source.
The chart would seem to refute that, the time frame for pressure spike was about the same, just the pressure was much higher in the smokeless.
To answer the 1st question, it's not the brass, but the cylinders, made of modern steel and for cartridges, the ROA is actually a modified old model Blackhawk, made of the same metal as the Blackhawk, in revolvers the bulk of the pressure is in the chamber, some dispersed by the barrel/cylinder gap, so the barrel gets a reduced pressure push for the bullet/ball.So now I need to ask, 45C cartridges loaded with smokeless for use in a modern double action revolver, S&W 25 in my case, safe to use in my ROA and R&S with conversion cylinders. Does that soft brass case make that much difference, the steel in the conversion cylinders much stronger. So far neither ROA or R&S have shown any adverse effect. I load in the moderate zone on all reloads regardless of caliber.
in revolvers the bulk of the pressure is in the chamber,
High pressure spikes with very light loads in Smokeless cartridges are very difficult to document. Some shooters insist they cannot happen. I have never heard the static charges explanation before.
What I have heard, and tend to give credence to is a phenomenon called premature shot start. The theory is that with a very light load of Smokeless powder, as the powder begins burning it may build enough pressure to push the bullet out of the case, but enough pressure has not been generated yet to keep the bullet moving down the barrel. So the bullet stops moving, often in the forcing cone. An instant later, because the volume where the powder is burning has now become finite, the powder begins its normal progressive burn, but the stuck bullet now acts as a barrel obstruction. The pressure builds much higher than would normally happen because the bullet cannot get out of the way fast enough. In extreme cases, even with a small charge of powder, the pressure gets high enough to burst the cylinder.
When loading very light loads with Smokeless powder it is important to crimp the bullet very firmly, so it will be retained in the case until the pressure builds enough to keep it moving down the bore.