Proofing ML Barrels?

[Loyalist Dave]

Hey Folks.

I am trying to find out what the load would be for proofing a black powder barrel according to the CIP standards. The C.I.P or the Commission Inernationale Permanente pour l'Epreuve des Armes a Feu a Portatives sets the standard that proof houses must meet when proofing guns. Pedersoli proofs their barrels at the Italian National Proof House which follows CIP standards.  I can only find references to a CIP standard of 125% and 130% of max loads for cartridge guns. I cannot find a reference that states what the percentage is for muzzleloader barrels, or what the load is for each caliber,  or the max load from which they derive the proof load. Anybody have a source?

I ask as I am not trying to proof a barrel. I was told that Pedersoli proofs barrels in muzzleloaders at 300% of the max load..., which I find rather high, though 125% of a smokeless round might have the same pressures as black powder 300% load.  I am just wondering, or did somebody misread "proofed to 30% above the max load" and added a zero to the figure?

LD

[bluelake]

Unless the barrel was exceptionally long, wouldn't powder over a certain amount just not burn and, thus, just be wasted?

[Loyalist Dave]

Unless the barrel was exceptionally long, wouldn't powder over a certain amount just not burn and, thus, just be wasted?

Well yes, but more would detonate than would be expected, AND the major flaw in that myth is the lack of accounting for the mass of the powder.  For example say when you filled up a gun barrel (as the myth goes) and fired it with it topped off with say 2Fg and the barrel took a full pound of powder..., and lets say two ounces detonated for like an 875 grain charge in the barrel..., leaving a whopping 14 ounces of powder resting on top of the detonated two ounces of powder.   Now in the split second the detonation occurred the mass of the powder would start to decrease as it is forced from the barrel, but the inertia and the time necessary to force the powder out would cause a huge pressure spike.  Let me put it this way..., would you fire a barrel with an 875 grain charge with 14 ounces of lead shot (mass is mass after all) if the shot column was flush with the muzzle of the barrel and would begin to exit and reduce the internal mass of the lead the moment the gun was fired?  (OK well the shot would have more friction but would that be that much different?)  

Anyway, I'm looking for the CIP standard.  I have had folks tell me it's the same for cartridge guns, but then how do they come up with the "max load" to derive the +25% to create the proof load.

LD

[bluelake]

the major flaw in that myth

Is it really a myth?

[Captchee]

does this help you any ?

4.6. TECHNICAL ANNEX TO THE STANDARD REGULATION FOR THE CARRYING OUT OF INDIVIDUAL PROOFS OF WEAPONS USING BLACK POWDER (ANNEX TO 4.5.) [XIX-7 Annex]
1. Properties of the black powder to be used for proofs.
Reference powder
A black powder with the following physico-chemical properties has been chosen as the ref-erence powder for the study of pressures and to determine the quantities of the proof charges:
a. Moisture content: max. 1,3 %
b. Density: 1,70 - 1,80 g/cm3
c. Granulometry: 0,63 mm max. retained: 5 %
0,20 mm max. passed through: 5 %
d. Chemical composition:
- percentage potassium nitrate 75 ± 1,5 %
- percentage sulphur 10 ± 1 %
- percentage charcoal 15 ± 1 %
e. Ash: max. 0,08 %
f. Hygroscopicity (12 h): max. 1,8 %
g. Bulk density: min 0,85 g/ml
The above values are given for guidance, the pressure of the reference cartridge (Paragraph 2) being of principal importance.
2. 16-bore reference cartridge
The purpose of this cartridge, filled using charge components, is to enable the pressure de-veloped by the reference powder to be measured.
The cartridge shall be filled using the following components:
- Case: 16-bore for smoothbore arms, length 67,5 to 70 mm, with 8 mm long metal head.
- Primer: "double strength" FIOCCI No 616 or equivalent.
- Black powder: 3 grammes.
In order to avoid any compression, the powder shall be put into and contained in a card-board or plastic cylinder placed at the bottom of the case, of thickness of approximately 0,6 mm and a depth that takes account of the volume of powder.
- Wad: greased felt wad, 10 to 12 mm in depth.
- Shot: 33 grammes of 2,5 mm-diameter lead pellets.
- Crimping: round with a 1,5 mm thick cardboard sealing dis.
- Length of the made-up cartridge: approximately 64 mm.
The pressure developed by this cartridge shall be measured in a standard 16 x 70-bore pressure barrel manufactured in accordance with C.I.P. provisions.
Before the proof, the cartridges must be conditioned for at least 24 hours at a temperature of 21º ± 1ºC and a relative humidity of 60% ± 5 %.
The above mentioned cartridge, filled with the reference powder, must give a pressure, measured electromechanically, of Pn = 275 ± 25 bar.
The measuring system shall include a piezoelectric transducer capable of measuring up to 2.500 bar, with a natural frequency of 100 kHz, min., showing a maximum deviation from linearity of 1% and a sensitivity of 2,0 pC/bar min.
2001 4.6. 2
3. Proof charges
The prescribed charges are as follows:
Calibres    Pressures
for
guidance    Proof charges    Maximum service
charge       
(bar)    Powder (g)    Shot or bullet    Powder (g)   Shot or
bullet    
10
12
14
16
20
24
28
32
36
9
.31 ca. 7,9 mm
.36 ca. 9,1 mm
.41 ca. 10,4 mm
.44 ca. 11,2 mm
.45 ca. 11,5 mm
.50 ca. 12,7 mm
.54 ca. 13,8 mm
.58 ca. 14,7 mm
.69 ca. 17,5 mm    750
800
850
1200
1400    13
12
10
9
8
6
7
8
9,5
10
13
14,5
16,5
20    65
60
55
40
30
10
12
16
19
19
24
28
31
45    6,5
5,5
5
4
3,5
2,5
3,5
5
6
6
8
9
10
12    36
32
25
22
17
6
8
12
15
16
20
28
31
40


4. Proof procedures
Smoothbore arms shall be loaded by placing a felt wad of at least 20 mm depth on top of the powder (without compression). The projectile shall consist of shot pellets of a diameter of 2,5 - 3 mm, held in place in the barrel by a felt wad of at least 10 mm depth placed over them.
In the case of firearms with a rifled barrel, loading shall follow the same procedure as that laid down for smoothbore arms, using a bullet instead of shot and without a wad.
5. Proof charges for pistols, revolvers and firearms of special design
In the case of pistols with one or more barrels, the proof firing of which in accordance with Paragraph 3 and 4 is not possible, the proof charge shall be determined, taking into account the length of the barrel(s), according to the maximum service charge laid down for that type of firearm. The quantity of proof powder must be twice the service charge.
In the case of revolvers and firearms of special design which have a powder chamber or primerless cartridge which cannot accommodate the proof charge provided for in Paragraph 3, the chambers shall be filled with the maximum amount of reference powder they can hold. The bullet shall be inserted and pushed in until flush.
6. Diameter of the touch holes
Firearms using black powder must be equipped with nipples having a touch hole with a maximum diameter in the direction of the chamber of 1 mm.
2001

[Captchee]

dang , the graph got all messed up  
 ok so if  the above sounds like what your looking for or if it will help you . PM me your  e-mail and ill send it to you  in PDF .

 the thing to remeber is that max load  of say production guns , is not based on just the barrel  but also the ability of the  lock to  withstand the blow back.

 the above i recieved by request from the bermingham house

 i would shoot them your question .  they have always been willing to answer any questions i have sent them . sometimes it takes a while but they do get back to me

http://www.gunproof.com/Proof_Memoranda/proof_memoranda.html

[huntinguy]

On page 86 (1975 edition)
Italian National Proof House. The following are proof load for revolvers, rifles, and the Zouave

Gun and Caliber                     Proof Pressures
Revolvers        
.36                                          9,245psi  
.44                                        10,667psi
Rifles
.44                                        12,089psi
.45                                        13,512psi
Zouave
.58                                           8,818psi

The Spanish National Proof House
Loads- They are submitted to a minimum pressure of 700Kgs.cm2, (9,956psi), the firearm being completely finished and assembled or in blank, but with exact dimensions.

Or so that it what is in the Lyman book.

Is that what you wanted?

[Loyalist Dave]

Thanks, yes that's much closer.  I knew somebody would have something for me as a source.  I was and am still looking for a source that says, to proof a gun barrel, the caliber of the barrel (X) was used, with and it was determined by formula (?) that a load of (Y) was the maximum service charge, and (Y) was multiplied by a percentage of (Z) to determine the proof charge, which was then fired with a (?) weight patched lead ball, and then the barrel was inspected.  

And the powder story is a myth until somebody actually documents doing it.  I have heard lots of stories starting waay back in 1976, about what will happen, but not when it was actually tried.  

You see I bet a thick walled rifle barrel, or even perhaps a slightly thinner rifled musket barrel would hold..., but a shotgun or a smoothbore musket barrel..., I would want to be at a safe distance and have a remote camera recording the test event.  

For if the detonation was continuing in a thin walled musket barrel, and passed beyond the breech, the thin walls of the barrel probably would not hold that pressure.  That's the hypothesis, until I get enough money saved to buy a Pedersoli Barrel for a bess, top it off with 2Fg, prime it with cannon fuse, light it and run while a video camera sits near by.  Should be good for a YouTube spot if nothing else.

LD

[Bigsmoke]

Even the thin walled barrels are mighty rugged.  For example, my 8 bore double rifle's barrels are about .114" thick at the muzzle, measured from the groove to the outside diameter.
Service charge is 300 grains Fg and it shoots a ball weighing about 850 grains.
The only thing I have recorded as expanding, bulging or blowing up is whatever was in from of it when the trigger was pulled.

[LRB]

Black powder does not detonate. It explodes. There is a difference. Detonation takes place at a rate faster than sound. An explosion is a just a really fast burn.

[Loyalist Dave]

Actually, it deflagrates which is confusing as the term supersonic detonation is often found in many texts, yet that is redundant, for by definition a high explosive is thus because it detonates and the gases move at supersonic speeds.  Black powder being a "low explosive" causes most folks in lay terminology to expect the term "detonation" when in fact it should be called deflagration.  A very fast deflagration, as a campfire is also deflagration.  Further there are those that think that like smokeless gunpowders that burn when not compressed, black powder is similar when not compressed, when it is not.  Most items that deflagrate are shipped with a "flamable" label when being transported, while BP is transported as an explosive as are the  explosives in the  "high" category.  Quite confusing really.  

LD

[LRB]

Ed Zachary!