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HuecoDoc
06-06-2008, 09:49 PM
Could someone please clarify something for me? The N-SSA rules state these two things:
1-A cannon with a reduced bore is considered a scale replica gun, and is, therefore, not allowed, unless already in N-SSA use as of February 1, 1996.
2-No reproduction barrel shall be approved after March 1, 1986, which does not have one caliber's thickness of metal surrounding the bore at the breech.

How is it possible to reproduce a Model 1841 Mtn Howitzer that would satisfy both rules? For a 4.62" bore to be surrounded by 4.62" of metal, breech diameter would be 13.86" where it is supposed to be 6.3"!

Even if one only needs to reinforce the diameter of the original 3.34" powder chamber, outside dimensions of the barrel would need to be altered.

Thanks.

06-07-2008, 02:59 PM
Please give me a call
757 868-0570 home
757 688-5464 work

Rob West
N-SSA National Artillery Officer

CrufflerSteve
07-24-2008, 12:29 PM
I'm no expert but I thought the Mountain Howitzer has a chamber smaller in diameter than the bore. The caliber is calculated from the chamber not the bore since the powder ignites in the chamber. I guess if someone did a repro Mtn Howitzer without full size bore and no chamber it would not be legal.

Steve

HuecoDoc
07-25-2008, 12:15 AM
Even if one only needs to reinforce the diameter of the original 3.34" powder chamber, outside dimensions of the barrel would need to be altered.

Edwin Flint, 8427
07-25-2008, 02:52 AM
Huecodoc,

Although I am not an expert, I think you are misunderstanding the rules. Since I am currently unable to sleep, I thought I would try to clarify them for you.

One Caliber is one inch, not the bore diameter of the artillery piece. Most people forget that a 50 caliber is actually .50 Caliber(diameter), a 58 a .58 Caliber (diameter), etc., they forget the decimal point in front of the numbers.

In the N-SSA, All reproduction Artillery, including Mountain Howitzers, must have External and bore diminsions identical to what was required in the original specs for the piece. ( The exception being those scale pieces that are grandfathered in prior to the rule change.) It is the liner the rules require to be one caliber or 1" thick at the breech. The rules require a specific minimum strength of steel and the bore have 3/8" steel liner. Reproduction tubes must have a liner that meets the standards in the rules. The rules require that the liner be one caliber (inch) at its thinnest point in the breech. The tube is then cast around or attached to the liner in one of the approved methods.

If I am wrong, please someone correct me.

Call Rob and he will answer all of your questions, I am sure.

CrufflerSteve
07-25-2008, 10:33 AM
Huecodoc,
Although I am not an expert, I think you are misunderstanding the rules. Since I am currently unable to sleep, I thought I would try to clarify them for you.


I think you are misunderstanding 'caliber'. This is not another term for inches. Inches are a good way of describing it. A typical Civil War rifle will have a .58 inch caliber. A 3 Inch Ordnance Rifle has a 3 inch caliber.

Since casting was not that great in the 1860's, a thickness at the breech that was at least the equal of the bore diameter was regarded as necessary for safety. The bigger the bore diameter, the more metal needed at the breech. One way to work with this was to have a powder chamber that was smaller diameter than the bore. This powder chamber would have thicker walls than the bore and manage the 1 caliber.

I think the liner alone on my 2.25" Mountain Rifle would be sufficient for live fire but it would be totally period incorrect. A proper liner gives us a great safety margin.

If I am wrong please correct me.

Steve

HuecoDoc
07-25-2008, 02:28 PM
Edwin, if you are right that certainly casts things in a different light.

In regards to casting quality, as I understand it the quality of 1860's casting is not the concern, ironically it's the quality of 1950's reproduction attempts that were the main concern when the N-SSA rules were initially written.

threepdr
08-22-2008, 04:57 PM
Ed,

In artillery terms a "caliber" relates to the bore diameter of that particular tube. For tubes is it used to give a reference for length and exterior diameter of the tube in relation to bore size. For example a gun will normally be 14 -16 calibers long (ie 16 x bore diameter) and a field howitzer is about 10 or 11 calibers long.

The same type nomenclature lives on in modern times. For example the most common WWII 5 inch naval gun was called a 5inch/38 because the tube was 38 calibers long (190 inches).

Edwin Flint, 8427
08-25-2008, 01:15 AM
Mark,

I said it before, and say it again, I don't know artillery. I had hoped that there would be an answer on the board by an N-SSA member that knows what they are talking about. I have read the rules and thought I understood what was required. Since an artillerist didn't answer, I did my best to explain the rules to the gentleman who was a visitor to the board. (I gave the them over a month to respond to the gentleman's question.) It also appeared that only non-N-SSA members were responding other than a request for off board contact. I thought the question should receive a response from an N-SSA member on the board.

I am pretty good with small arms but don't know everything there, either. My experience with the term caliber is with small arms. I defer to your greater knowledge of artillery.

This however is what caused the confussion in the first place for the initial poster. Read the initial post. No way to make the mountain howitzer he wanted to reproduce the correct external dimensions with caliber defined as you described. Somewhere, there is a breakdown in terms. If a Caliber is 1", it is possible to meet the external dimensions.


I am curious about this. Please, someone that knows the rules and requirements explain the difference.

paul w/McGregor's 385V
08-25-2008, 07:03 AM
Ed,
You are incorrect. An Artillerist did indeed reply. Rob West posted his phone numbers.

Rob is an active member of the N-SSA, and a builder of replica artillery, I believe Rob to be highly qualified to answer the questions that may be posed.

Take care and be safe
pfb

Minieball577
08-25-2008, 07:32 AM
I am pretty certain Ed's point is that the reply could have been public, thus clarifying the issue to all who had read the post, rather than a private communication.

Edwin Flint, 8427
08-25-2008, 09:15 AM
My point exactly. Thank you Mr. Hubbard.

Read what I said again.
...non-N-SSA members were responding other than a request for off board contact.
My response came about six weeks after the initial post. Mr West had answered with his phone numbers, but the discussion continued about our rule requirements among NON-N-SSA members. (I think there were more posts than are showing now from Non members.)

As unqualified as I am on artillery, I at least, have read the rules and have some knowledge of our requirements. As a lawyer, I try to read things in a way that makes sense. What I came up with was the only thing that reconciled the differences.

Again, If wrong, I would like to know it.