PSI with black powder

[wszumera]

Can anyone tell me what the typical range of PSI a black power rifle operates at?

Thanks,

Clutch

 

[faw3]

I'll take a WAG at 7 to 10,000 psi on most guns, some run really hi but if used with a PRB it (the patch) acts as a safty by being blown out. :grin: Fred :hatsoff:

 

[arquebus]

Not too sure on the figures offhand, but PRB guns operate at much lower pressures than bullet guns do in similar calibers.

 

[paulvallandigham]

Some of the small bore guns have been measure at up in the 20,000 psi range using black powder. They are the exception, unless, of course, that is what you are shooting! The middle calibers,40-58, will run in the 12-16000 PSI ranges. The larger bore guns and smoothbores drop down below 10,000 PSI. There are many loads for 12 gague shotguns that are in the 6,000 psi range that produce excellent patterns. Once again, the pressures in the smaller bore shotguns will be higher.

 

[Zonie]

Paulvallandigham's answer is about right for black powder loads however if you are loading sabots or slugs like the MaxiBall and shooting Pyrodex or similar substitute black powders, the pressures shown in the Lyman BLACK POWDER HANDBOOK can be as much as 28,000 - 31,500 PSI in a .50 or .45 caliber gun.

These pressures are getting up into the smokeless powder pressure range and if your shooting a Black Powder rifle which has a Spanish Proof mark, I suggest that they not be used.

zonie

 

[paulvallandigham]

Thanks Zonie: I had just read the prior post mentioning PRB and that is what I assumed the post was asking about. Conicals, particular the new sabots, with heavy pistol bullets, or the 50 caliber lead bullets made for shotguns do push the pressures up to the 30,000 psi range. Most traditional ML rifles and smoothies are not intended to be used in that pressure range, and should not be used with these loads.

Most people are rather surpised to find out that even a PRB can create a lot of pressure in a barrel, or that the pressure can be high enough for things to come apart if they are not a good fit. I occassionally see here comments by members who are using 2 PRB as a " Bear Load " in their rifles. I would want to know for sure that my gun can take the increased pressure such a load will generate, before using it to protect my own life in the field, hunting such dangerous game. My .62 ca. fowler is a well built smoothbore, but I am not sure I would want to shoot 80 grains of FFFg powder using two .62 cal. round balls in that gun. Things could get a lot more exciting than I had planned.

 

[Mad Professor]

Paulvallandigham's answer is about right for black powder loads however if you are loading sabots or slugs like the MaxiBall and shooting Pyrodex or similar substitute black powders, the pressures shown in the Lyman BLACK POWDER HANDBOOK can be as much as 28,000 - 31,500 PSI in a .50 or .45 caliber gun.

These pressures are getting up into the smokeless powder pressure range and if your shooting a Black Powder rifle which has a Spanish Proof mark, I suggest that they not be used.

zonie

I second Zonie's advice. Spanish barrels are proofed at 10,000 psi so I'd keep any loads to ca. 8000 psi.

 

[RedFeather]

I would not want to try a two ball load because of the off chance that one ball might migrate away from the other. Then you have the back ball slamming into the front one and bulging the barrel or worse. If you feel the need for that much knock-down, go to a heavier slug.

 

[Dave Rosenthal]

The heavier slug idea is a good one! I once used a chrono to track how a .50 cal 470 grain T/C Maxi-Hunter behaves with a 100 grains of 3Fg Goex behind it. At almost 1400 FPS it will rock your world! I don't recommend that anybody else try it, but MAN, that EVIL watermelon was blown to bits! :shocked2:

A member of one of the clubs I belong to was quoted as saying, "nothing in this Country needs more killin' than that!". I tend to agree with him! :grin:

A single heavy slug is the way to go!

Dave

 

[Runner]

Randy Wakeman's ugly lies being repeated on the Muzzleloading forum by Zonie! Shame on you!

The Spanish government requires a certain proof for barrels that are sold for Muzzleloading. The governemt proof is stamped on the barrel. While being paid by Knight, Wakeman started this whole idea that the barrels were weak because of that stamp. That stamp has nothing to do with the failure strength of those barrels. It is a simple government requirement.

I have touched off way more 3f 777 under heavy conicals than any of the current manufacturers recommend. I actually blew a barrel out of the stock part way from the severe recoil breaking the stock at the wedge. The pressure on that barrel was in the heavy modern range. It still wins shoots. In the 70's they packed a CVA barrel full of powder and put a conical down on it so that the pressures would be higher than roundball. The power was harmlessly blown out of the barrel. Since the Wakeman scandal, a popular brand of barrels here on the forum was found to fail well before one of the Spanish barrels did.

The danger with black isn't too much powder or heavy bullets. Black destroys by using a short started plug in the end of the barrel, or by what is called a middle flash by us ignorant savages. If the powder in the column is ignited in the middle of the load, the pressure wave runs both ways and then meets itself. This is what makes the heavy loads so dangerous with the modern so called muzzleloaders. The powerful primer can cause wild pressure variations using some of the replacement powders, depending only on where the actual ignition is obtained. Knight produced a gun that had a long snout on the nipple so that the powder was deliberately ignited in the middle of the load to increase the pressure. It produced staggering ballistics for a muzzle loaded gun of that time period.

The Spanish government proof is no indication of the strength of the Spanish barrels. For that info you would have to be privy to designer info from the companies involved. Wakeman was told to go jump in a lake by the companies involved so he used it to prop up his written By Knight rant at the time. If youu smell smoke, something is burning. If you smell something else, that is likely Wakeman.

In the 70's, in response to a wave of lawsuits where supposedly high quality barrels were supposed to be blowing up from black powder, Green River demonstrated just what a black powder barrel from them would take. They cut slots, sight grooves, cuts length ways, drilled enough holes that with screws in them the barrel would not touch the table if you put it down. If I remember correctly, it took 600 grains and 6 balls on top of thwe frankenstien bazrrel to create the first bulge. 1200 and 4 balls I think finished it off so that they did not trust to continue the test. It was published in Muzzleblasts along with pictures.

Wakeman's BS caused Sports Authority and several other stores to get out of the traditional muzzleloader business. It was nothing but a lie in support of his master of the time. The damage may never go away if people like Zonie believe that crud.

Zonie, do your own research on it.

 

[Zonie]

My comments about Spanish guns was not based on Mr. Wakeman's thoughts or comments. It was based on my own thoughts.

Spanish Black Powder gun barrels are stamped with a number which looks like this:
700 kp/cm²

The stamp represents a pressure, and if converted to an English pressure it is around 10,000 Pounds per Square Inch.

I have always thought this may represent a safe working pressure, "working pressure" not being necessarily what the absolute maximum pressure could be.

If I am right, it is entirely possible that the barrel could take over 25,000 pounds of pressure without exploding however it may be unsafe to push the pressures that high without risking ones own life.

Anyway, for now, I will stick to my comment that I personally would not subject a Spanish gun to pressures above 15,000 PSI. If others wish to do so, that is their business.

zonie

 

[Runner]

The government requires that proof to sell the gun Zonie. It has nothing to do with the design strength of the barrels. It is the result of an old law that is still a requirement. I shoot roundball pretty much, but I have no fear at all of touching off silly loads under heavy conicals in any of my Spanish barrels. My opinion does not come from a proof mark or even from stories. We used to load them up and then double ball them just to watch the recoil hammer whoever we could convince to shoot it! My Hawken in 1-48 has had several hundred 385's thru it and none of them had less than 100 grains of black, pyrodex, or 777 under them. I am a hands on kind of guy. When 777 came out, I watched until it hit a local store. I did a two can test of the 3f 777. Like I said before, I ended up ruining a stock. The barrel is fine. I have no problem when people post real safety concerns about various muzzleloaders. The Navy Arms Country Boy 12 guage should be removed from the market because of safety issues. Some of the Traditions Deerhunters have a lock that will release when the hammer is pushed sideways because tolerances are so sloppy that the tumbler moves enough to release the sear when it is pushed from the side. These are real straight up issues that I have had in my hand and have looked at the problem and the cause. If the Spanish barrels were as weak as some seem to think, I and several others I know would not be here any more.
The effect of the don't trust the Spanish barrels message does nothing but run newcomers that just bought one away from the sport. That would be acceptable if there was a real safety issue.

 

[faw3]

You must mean bigger since Ive had no luck with slugs out of smooth bores as of yet. FRED :thumbsup: (while Ive shot a few 2 ball 62's I'm not doing it out of double barrel hand guns no more that HURT'S :surrender:while a builder on here shoot's 5 at a time stake busting just once was enough for me. :surrender:

 

[Zonie]

Runner: Thank you for the information.

As you seem to have knowledge of the Spanish markings, perhaps you could tell us why they chose to use "700 kp/cm² "?

What is the significance of the number and why did they choose to use a pressure rather than one of those neat Crowns with letters under it like they do on other Spanish guns?

zonie

 

[windwalker_au]

zonie check out the traditions site click on any of there side locks and then click on there owners
manuel in pdf you will be quite suprised at the max loades they list for there guns these loads will give a lot more than 10000 psi,there max load for prb is also there max load for a mini or a maxi.
bernie :thumbsup:

 

[Runner]

I don't have the links anymore Zonie. I was Wakeman's original heckler when he started that crud. We contacted all kinds of folks over months. The proof house is a government thing as was common not to long ago. The proof on the barrel is the proof level that has to be met to sell the gun as a muzzleloader. The original discussion was on another forum, and the files no longer exist online.

After the mark was verified as being a government requirement, Wakeman then demanded that the companies selling those barrels to the public turn over their internal testing data. They laughed at him. If they say the barrels are super strong and publish a pressure limit, then you have guys that would be loading right on the line all the time. No matter what they had to say, it was going to get twisted anyway. They did the correct thing and stuck to their loading manual. The manual for my Hawken 50 if I remember correctly had an upper limit of 100 grains of 2f under a conical no heavier than 400 grains. In later years that was reduced to 90 grains in the booklets I think. That would be your target safety pressure you would compare loads with.
It would be intersting to actually be able to check the pressure difference between a double ball or Bear load using patched ball and a soft lead conical with no patch.

 

[paulvallandigham]

I have to stick my nose in here a bit. No one should consider a .50 cal. conical of up to 400 grains in weight, shoved down range by 90 grains of powder to be a weak load! The military used the .50-70 cartridge, shooting a 550 grain bullet in the late 1860s, before adopting the .45-70 in 1873. The .50-90 was called " The Big Fifty" because of its powder. Using a bullet under 400 grains would give some added zip to the bullet, flatten trajectory, and still be hitting the target with 3/4 oz of lead, spinning around a 1/2 inch axis. This will penetrate both sides of a buffalo, or kill 3-4 men standing in a row.

Why would anyone want to put more powder in these rifles using conicals???? Is your love life so inadequate that you have to use your testosterone on the range?

 

[Mad Professor]

While we are (back) on this subject..........

I asked a while ago if ANYONE had a manual with PSI for loads in a 12 ga BP ML (shot not slugs). If so, could you list some of the data?

Thanks in advance.......

MP

 

[paulvallandigham]

MadProfessor: I am not aware of any such data in any manual. I even called Lyman a few months ago looking for the same information, and they did not have it, nor have any plans to produce such a manual. Apparently they don't believe there is any demand for such data.

Perhaps if all the smoothbore shooters here on MLF would write letters to Lyman requesting such data, they might change their minds. It would make an excellent supplement to their current Lyman Shotshell Handbook.

 

[Runner]

Paul, no one said that it was weak. It is a normal load for the so called weak Spanish barrels that is posted in the manuals and is safe to shoot all day long. It kind of kills the weak Spanish barrels BS straight up.
Yes, somewhere there is a comparison between the pressure differences using 2f and 3f across a wide range of caliber. The 12 guage was in there. I don't remember where it is, but I seem to think it was from a guy out of Texas that claimed that 3f caused throat erosion in muzzleloader barrels.