Conflict in various load charts

[Rickk]

(Moderators note: This was origninally posted under the More Complete Cannoneer topic and is defintely on topic there.  But the issue referring to contradictions in loading information in The More Complete Cannoneer makes for a very good discussion topic of its own, so I have split it out. Thanks for posting it Rick. DD)

There should be a new revision of the book either out now, or out very very soon. when you order it, find out what edition you are getting. If the new one is out, please let us know. I had heard a few months ago that maybe the new release would happen in August 2006

One issue I see, not particularly about the book specifically, but about the book verses the n-ssa rules verses a few other artilliary association rules is that they all seem to quote basically the same load tables/recommendations, but do not quite make it clear what conditions they are to be used in. I was hoping that "The Book" would clarify the confusion, but it adds to it.

I am hoping the new revision clears that up.

Depending on which source you look at, the load tables and recommendations, whiles all very similar,  are either:

- For blank loads, and should be reduced with live loads.
- For live projectiles ( often with a recoommented projectile weight that corresponds to a solid round lead ball projectile ), and sometimes the suggeston that the loads can be doubled for blanks
- For live projectiles, with no suggestions about blanks being any different.
- For 1F or Cannon powder, as though they are interchangable.
- For Cannon Grade powder, sometimes with implications that the suggested loads for blanks should be the same, but with 1F being ok instead.
- For unspecified powder grades, with or without a projectile.

Also, the chart for sub-2 inch guns does not have powder size mentioned their either. There is no way one is going to use cannon grade in a 1/2 inch bore, and at the other end of the spectrum, 3 or 4F in a 1.5 inch bore is going to cause problems (especially with a projectile). There are no guidelines about what to do with blanks in smaller mini-guns. In my experience, with guns around 1/2 - 3/4 inch  and absolutley no wad at all you are only going to get a poof or maybe a woosh, not a bang.

I have taken a conservative assumption, that all posted recommendations are for blanks (1F) and that they should be cut in half and Cannon grade be used for live projectiles. The assuption is based on the safest total combinations of all reccomendations I have found from all the "official" sources. I have no idea if I am being way too conservative or not, but at least probably I won't take up column space in the newpaper (at least not for exploding cannons).

My assumptions for the mini-guns with blanks I will keep to myself.

Has anyone seen the new edition out yet, and are there any significant changes/clarifications in the load tables?

Rick

[Double D]

I don't really think the load data in the book is all that bad. The bad part is the organization of the data.  Bits and pieces of it are all over the book, but when pulled out it is for the most part fairly consistent.

Switlik says a commonly accepted rule to limit powder charges for field guns over two inches is 2 oz of powder per inch of bore diameter. (pg 105)  He is rather vague on powder grade but if you read the section in which the guidance appears he mentions the use of Fg and larger.  This same section also has information on pressures test with full service loads of Cannon grade.  When FG was substituted it produced pressure 40% above the normal design operating pressure.   Given that statement it would seem that he would differentiate between the two powders.

The Artilleryman Magazine Safety Rules posted in Switlik's book as Appendix II says Maximum charges are 2 oz of FG and 3 oz cannon per inch of bore for guns over 3 inches. 3 oz of FG and 4 oz cannon per inch of bore for guns for 2 to 3 inches. Use reduced loads for projectiles

The N-SSA rules in Appendix III presents a load chart, and lists both a maximum powder chart and ball weight.  A careful look at the chart shows that powder weight seems to follow for the most part the rule; 2 oz per inch.  Powder must be Fg or larger grain

These three recommendations do not seem to me to be all that vague. They don't exactly agree, but they are not in conflict with each other.

They are maximum loads recommendations This is where they get vague. This is where we on this board seem to have difficulty.

Is this a maximum load for projectiles or a maximum load under all circumstances?  The point; Blank charges. 

Switlik states that “up to twice the amount of powder recommended above for ball loads can be safely used for a blank load.”    That give the impression that he is saying that 4 ozs. per inch would be safe for a blank.  That is with no wad by the way.   If you read Switlik’s entire chapter on Ammunition you will see he does mention the use of FFG powder for blanks loads in full size guns. 

The Artilleryman Magazine Safety Rules says use reduced charges for projectiles. Their rules do not clearly identify what charge to use for blanks, so we are stuck with assuming the Max charge is the max charge.

N-SSA is a live fire organization and their rules don’t address blank fire.

So which is right?  I hope Switlik addresses that in his updated book. 

Also addressed is the issue of projectile weight. Switlik says the “consensus among experienced cannoneers” is that the projectile weight should not exceed that the weight of the original.

The Artilleryman Magazine Safety Rules say projectiles should weigh no more the one half the weight of projectiles used in the original guns of the same bore diameter.

N-SSA maximum projectile weight is fairly close to original weight of a solid iron shot for the bore.

Switlik book is more for the shooting large a full scale guns, greater 2 inch bore.  Most of use are not using large or full scale guns.  Our guns are smaller some a lot smaller.   That doesn’t mean what Switlik puts forth in his book is invalid.  Most of what he advocates for the big guns applies to the little guns.  Switlik dedicates his Appendix I to cannons of .5 to 1.5 inch bore diameter.   Switlik provides us with prudent load chart but fails to tell us which grade of powder to use.  I would like to see him clarify that one point.  Personally I would not use anything finer than FFG in a cannon this class. 

There are some who want to use the recommended loads for muzzle loading rifles and pistols of comparable calibers of our cannon.  If you use the same loading technique I don’t really see any harm in that as far as overloads. The grade of powder recommended is also useful.   The danger with rifle and pistol loads is in the excess recoil generated.  Not only can that damage your carriage but it can make your cannon a projectile.

I hope Switlik these areas.

[GGaskill]

I have seen the following recommendation for loading for blanks (in the South Bend Replicas catalog, I think) in cannons.  It requires some work on the part of the gunner rather than being a "here it is" answer.

Starting with a small charge, fire and evaluate the report.  Increase the charge and try again, until a satisfactory report is achieved.  Then stop increasing.

Pretty simple.  Should be applicable to all bore sizes and grades of powder as long as the gunner uses some sense for the starting load and the increments.  Does require some work on the part of the gunner.

[Rickk]

Here is a specific for-instance of confusion and contraction between various "expert" opinions.

In Appendix III of "The more Complete Cannoneer", page 188, is a repring of NSSA rules. I think they have been modified since the book was published.

However, using that chart, for my 2.2 inch bore gun, here is what I get out of it for firing a live projectile:

I can fire a 21 ounce projectile.

I can put behind it 4.4 ounces of what I think is 1F powder. I think it is 1F because only for the 4.6 inch bore is there a note about using Cannon Grade only.



Then, from Appendix II, page 179, here is what I get:
2 to 3 inch bore gun, 3 Ounces of 1F for a blank, and "Use reduced loads for projectiles".

So, Per Appendix III I can use a 33% bigger charge behind a live projextile than I can with just a blank per appendix II.

Even if I misunderstood the grade recommendation of Appendix III (that they really meant Cannon grade everywhere in the chart, it still suggests a bigger charge of Cannon grade for a projectile than Appendix II recommends for a blank.

That is a contradition on a very large scale.

On page 103 , 2F is briefly mentioned as useful and then the subject is quickly dropped with no details

On Page 105, there is quoted the rule about 2 ounces per inch of bore diameter, and it is mentioened that this is acceptable with 1F powder and live projectiles. That would again have me using 4.4 ounces of 1F behind a projectile (consistant with Appendix III).

Moving to another source... current 2006 N-SSA rules, if I am interpreting them correctly tell me only about firing live projectiles, tells me the following:

21 ounce projectile max
4.4 ounces of 1F only... no recommendation at all for cannon grade for bores under 2.9 inches.

Then we have the curretn rules from the AAA, which state
"Powder charges should not exceed 2 oz. of Fg or 3 oz. FFA or Cannon Grade Goex powder per inch of bore diameter. No excessive charges. Use black powder only"
That is for firing a projectile (no mention of weight), so I can use 4.4 ounces of 1F or Cannon grade for a projectile.


So, 4.4 ounces of 1F for a projectile, and  3 ounces for a blank... one is safe, the other is either very conservative or somewhat dangerous, depending on which one you pick as being safe. which is it? I dunno....


There are other "official sources" on internet with other offical opinions as well. Several National Parks have cannon regs of their own, just to make it even more confusing.


This isn't a rant on Switlik's book, as he is mostly quoting other sources. However, since the other sources seem to disagree with each other, and this book is "The Book", I am hoping that the new release coming out in the near future helps sort this issue out.

[GGaskill]

Not having any of the source materials at hand, do any of them explain the procedures/processes used to reach these conclusions?

[Rickk]

nope.

The N-SSA and AAA rules are online.

http://www.americanartillery.org/aaa/marty.html
http://www.n-ssa.org/NATIONAL/RULES/Rules1-2006.pdf

Someone may have done some pressure testing to a limited extent, but it would be hard to extrapolate pressure testing  of one or two guns to make simple formulas that fit all guns or all bore sizes.

It would seem reasonable that they are largely the result of experience and reaction to situations that have occured in the past.

[GGaskill]

Charge values and pressure values are a recurring subject on the forum.  Here is one old example.  Here is one discussing velocity measuring.  I also posted (but cannot find since the Search is disabled) a link to this article at The Continental Line discussing Mr. Switlik's experiments.

[Double D]

First think it that Switlik pretty much backs up his point of view with some serious testing.  The Artilleryman Magazine Safety Rules and the N-SSA rules in the book don’t conflict that much.  It’s important you read the entire passage on Ammunition and the entire rules.  If you read only one paragraph or one rule you don’t get the entire picture.

There is a difference in the rules printed in Switlik and the Rules posted today on the internet. If you compare the printed rules in the book and the current rules it can confuse. The best thing to do is go to the most current rules  for the two organizations and us them and see what they say about maximum charges.  Let’s use a 2.2 inch gun.

Let’s start with American Artillery Association:

Powder charges should not exceed 2 oz. of Fg or 3 oz. FFA or Cannon Grade Goex powder per inch of bore diameter. No excessive charges. Use black powder only

So for AAA you can us 4.4 oz. of Fg or  6.6 oz of FFA or Cannon grade in your 2.2 inch gun.

The current rules for AAA are different than the rules published in Switliks book. The published rules restrict projectile weight to one half the weight of original.  The new rules make no mention projectile weight.

Now the N-SSA.  N-SSA  is much  more technical and has a lot of years of research testing and experience behind them

10.8.1 CHARGES
Maximum powder charges for all cannon shall be limited to that amount permitted by the chart as published below in Table 10.1. Only commercially manufactured black powder of American standard Fg granulation (150,000 granules per pound/ or 220 granules per 10 gr. wt. (avdp.) sample), or a coarser granulation, may be used. Charges must be wrapped in a powder “bag” fabricated of at least one complete layer of heavy-duty aluminum foil. For each match the ammunition chest shall contain two charges more than the number of rounds scheduled for that match; e.g., fourteen charges are required for a twelve-round match. Powder charges shall not be prepared at the site of any official skirmish. All powder charges shall be transported and handled in closed individual containers which protect them from punctures and leakage. In use, the powder charge shall remain in the container until the charge is received by the #2 cannoneer who shall remove the foil bag and return the empty container to the #4 cannoneer. The containers should be of a size that shall not permit them to be inadvertently loaded into the cannon tube, yet they must have an inside diameter which shall cause the foil bag to retain its shape for easy loading. Blank charges shall not be allowed.

A portion of this rule has been up dated since Switliks book was published, but the portion about the Grade of powders that may be used is unchanged.

10.8.2 PROJECTILES
Projectiles shall not be of a configuration or material which may cause unsafe pressures. Weight of projectiles shall be limited to that amount permitted by Table 10.1. Solid ferrous, combustible, explosive or pyrotechnic projectiles are prohibited. This shall apply to demonstration of artillery as well as competitive matches. Loose sand, soft clay or other malleable material is prohibited for use in cored projectiles. Conical or “minnie” type projectiles shall be submitted to the Chief of Artillery for approval. Saboted balls are not permitted to be used in any N-SSA artillery match, unless approved by the Artillery Officer.

TABLE 10.1 MAXIMUM POWDER CHARGES AND PROJECTILE WEIGHTS (amended 1/2005)

Caliber (inches)	Powder (ounces)	Projectile (ounces)
2.2	4.40	21

Again  we come up with a maximum charge of 4.4  grains using a powder no finer than Fg. 


Now Switlik

The other sporting granulations of blackpowder commonly available are Fg, FFg, FFFG, and FFFG. In past years Fg was the coarsest pow¬der generally available and was used in cannon, but recent research has demonstrated its potential for producing very high pressures and, if it must be used, charges must be carefully controlled and kept to a mini¬mum. Fg is very suitable for blank charges and produces full-bodied reports, without use of wads. The other granulations are never to be used for projectile firing in cannon. The potential for extremely high pressures is too great Use of FFg for blank firing is accepted in some situations, although to prevent confusion, the writer prefers not to have it in his can¬non ammunition supply area. The finest powders (FFFG and FFFG) can only be used in artillery igniters, primers, etc.

As you can see Switlik say  use FG for projectiles.  He mentions the use of FFG but in limited application for blanks only. He also make it clear not to use the finer grades in cannon applications.

For determining safe loads Switlik says this:

In determining a safe and yet efficient powder charge for muzzle-loading cannon one must take into consideration the type of cannon tube involved. A powder charge which is good for a gun, designed or propor¬tioned as a field gun, would be too heavy for a gun designed as a light swivel gun or a light howitzer. Whenever a person begins cannon shooting, it is prudent to start with an absurdly light powder charge.
One commonly accepted rule, for field guns over two inches bore diameter, is to limit powder charges in the ratio of two ounces of powder per inch of bore diameter…

On projectiles Switlik says:

It is the consensus of opinion among experienced cannoneers that the weight of any projectiles used in a full-scale gun, either original or reproduction, should never exceed the weight of the original projectile. A "six pounder" ball made of zinc alloys, like Kerksite, or other diecasting alloys, would seem to strike a happy medium, as they can be cast at temperatures only slightly higher than lead, but weigh slightly less than the same volume of iron.
Remember too, that some guns such as howitzers, mortars, etc. were designed only for shells—which were lighter than solid shot— maybe 1/3 lighter in many cases.

So again for a 2.2 inch bore we come  up with 4.4 oz. of powder as a max load.  2.2 ball is  1 ½  lbs or 24 ozs.

Seems pretty consistent to me.  Using FG powder the maximum amount of powder you should use is  4.4 grs.   Using AAA guidelines they say the maximum charge using FFA or Cannon Grade is 6.6 grains.

Now these are not war shots.  These are the maximum charge that these folks say may be used in their competitive cannon shooting,  in their venue. 

Those of use who have been around for a while both worldly and shooting cannons know the folks who created these rules are a combination of historians, engineers, scholars of the art of Cannon shooting, and cannon maker, with a bunch other just plain good folks tossed in for good measure.  They aren’t a bunch of good old boys standing out in a field saying “I used this much powder and my gun didn’t blow up so it must be good”.   These folks have studied cannon and cannon shooting for years.  The folks on the Cannon Safety committees for he N-SSA are some of the same guys that are on the Safety committee for AAA.  The two groups have slightly different goals and the same idea about safety.  Matt Switlik is involved with both groups. Read Switliks book and you will see the depth these folks have gone to make this sport safe.   This quote from Switlik book shows to what extremes these folks have gone to come up with these rules.  I for one do not question their wisdom, for their credentials are impeccable.

To investigate this situation further a group of artillery students con¬ducted pressure tests in the early 1970's using a replica of an 1883 crusher gage. In testing powders available at that time, it was found that 8 oun¬ces of Fg Sporting produced almost as much pressure as 16 ounces of a coarse military powder nearly identical to Civil War field gun powder, when fired in a 3" Ordnance Rifle with a full-weight projectile.
A much larger test program was conducted in 1986-87, using a piezo¬electric ballistics transducer to record time-pressure curves for a wide variety of blackpowder in a 3" Ordnance Rifle. The results of these tests were published in a lengthy article in the Artilleryman Magazine (Fall 1988) and print space does not allow repetition. In summary, these lat¬ter tests reinforced the wisdom of using Cannon granulation blackpow¬der or similar coarse granulation wherever possible. In one test situation, full service charges were fired with service projectiles using Cannon granulation in one case and Fg in the other. The Fg powder produced al¬most 40% more pressure than the Cannon powder (40% above the nor¬mal design operating pressure!) Remarkably, velocities recorded in both cases were essentially the same.

[Rickk]

Now look at page 179 of Switlik's book, last sentence...

"Maximum for 2 to 3 inch bore guns, 3oz Fg or 4 oz Cannon grade. Use reduced loads with projectiles."

If you look in the "Safe Loads" thread of this forum, the identical load is quoted (I believe they are the same source, so they should be the same).

So, 4.4 ounces Fg with a projectile Max      verses      3 ounces Fg Max for a blank (and less for a projectile)

That is the inconsistancy
         ---

I went to a re-enactment a couple weeks ago (n-ssa groups) and saw the aluminim foil wrapped charge they were putting into a gun. It was about twice as long as it was in diameter.

My 3 ounce blank loads (as recommended in our "Safe Loads" section) is just barely 2 inches long and about 2 inches in diameter. It is sometimes hard to make sure it goes down straight when being loaded because it is not long enough to not roll. This makes for sometimes inconsistant ignition. I found that putting a 1/8 inch thick cardboard over-powder wad into the top of the foil bag makes it just long enough to not roll any more when loading.

The charge I saw at the re-enactment caught my eye because obviously they do not have the same problem. The only way I can figure they could have such a long charge is if they are using a recommendation that is quite a bit different than the one that I am using.

[Double D]

As I mentioned I discounted the rules listed in Switliks appendix and went to the current rules posted by both associations.

But what you are pointing out is completely different.  The link we have on our board points to the Civil War news website  cannon firing rules that is an old version of AAA rules. The website pointed to  is not AAA.  I will correct outr link.

Use AAA and N-SSA websites for your guidance.

I posted some feedback to the webmaster of the Civil war news website.

[Rickk]

OK... please let us all know what the response from them is. I will really appreciate that.

It is rare that, with lawyers and legal stuff that safety recommendations go UP with time instead of DOWN, so I am wondering about the logic behind their lesser reccomendations.

[Double D]

Our post has been changed to point to the AA and N-SSA websites. 

[rusty barrels]

You know, I'm still a babe when it come to cannons and motars and I'm a long way from firing my first shot, but one thing I think I understand is every gun is going to have unique characteristics and no one has tested every type of gun ( like modern rifles and pistols have sammi standards ) So I think the bottom line is like the author of the book ( The more complete cannoneer ) stated was start out with a absurdly low amount of powder and work up from there. When mine is ready to go I'm planning on starting with 2 oz. fg  blank load on a 2 1/4" bore 2/3 scale 1841 6 pounder, 1 oz. with a 2 lbs ball. Oh by the way SUCCESS. I drilled the fuse hole and I didn't break any bits and it came in to the bore at about 1/4 of inch from the end and centered, right about where I wanted it.

[guardsgunner]

   Why not send Matt Switlik an invite explaining about the forum and some of your question and concerns and see if he will respond?
   Mr. Switlik did the testing from which the NSSA rules are based. The editors of the Artilleryman Mag. is an NSSA member.

[Double D]

Mr. Switlik is aware of our forum and has been invited to join us.  He granted permission for the post of the load chart for small guns.

[Cat Whisperer]

...
I went to a re-enactment a couple weeks ago (n-ssa groups) and saw the aluminim foil wrapped charge they were putting into a gun. It was about twice as long as it was in diameter.
...
The charge I saw at the re-enactment caught my eye because obviously they do not have the same problem. The only way I can figure they could have such a long charge is if they are using a recommendation that is quite a bit different than the one that I am using.

I have known some re-enactors that have mixed a large volume of flour in with the powder for more smoke.

[reddog]

I have A one inch bore cannon, .50 caliber muzzel loaders say 100 grains max for A projectile 1fg. So for A one inch bore would be 200 grains. The load chart on top of this page says for one inch bore max load for projectile is about 198 grains, very close. I shoot 3 ounce balls with 170 grains (under the max load) and I get guite A punch! ( goes thru A sheet of plywood like paper) I check my cannon after each shoot with calipers to look for any changes in dementions and have found none.