Talk:5-inch/51-caliber gun

Infobox?
This article could use an infobox: Infobox Weapon is appropriate, as seen in 5"/38 caliber gun. -MBK004 19:56, 11 January 2009 (UTC)
 * Done Thewellman (talk) 01:26, 11 August 2009 (UTC)

Delaware class BBs
These ships were equipped with 5"/50 guns (see Navweaps for the relevant technical info). Breyer is simply wrong if he states that the ships had the 51 caliber version. Conway's 1906-1922 has the correct information: "14 - 5in (127mm)/50cal". Parsecboy (talk) 12:32, 16 September 2009 (UTC)
 * As a contributor to Navweaps.com, I have a high opinion of the veracity of their information. However, I have an equally high opinion of Breyer's work and Campbell's text: Naval Weapons of World War Two.  I wonder why you are so quick to dismiss the latter two in favor of the former.  It seems at least possible the Delaware class battleships might have carried both guns at different times, and their listing in this article would be appropriate for their rearmament, even if their original equipment might have been different.  Do your references indicate otherwise? Thewellman (talk) 17:22, 16 September 2009 (UTC)
 * Friedman in "US Battleships" says 5"/50 in Delaware class as do other sources. Breyer seems unaware that the 5"/50 gun even existed as he does not mention it in his US Gunnery tables, he only lists the 5"/51.  Personally, I treat Breyer's as a tertiary source and would not recommend that you rely strongly upon the data presented.  No offense is meant by this, it is just that Breyer did his research back in the 1960s (published in 1970 in German) and many works based upon more recently opened records have been published since that time. Tony D.  23:15, 17 September 2009 (UTC)
 * Yes, Conway's All the World's Fighting Ships 1906-1921 has the Delawares as equipped with 5"/50 guns, and it makes no mention of them ever being rearmed with the /51 version. Parsecboy (talk) 04:35, 18 September 2009 (UTC)

Range
In response to an editor's question, I would like to explore the subject of significant figures as it might apply to encyclopedic coverage of naval artillery. The editor correctly asserts the difference between nautical and statute miles and the professional preference for expressing range in yards. Many laymen using this reference, however, will find the nautical mile confusing unless an in-place conversion is provided. Many would have similar difficulty conceptualizing a maximum range expressed in thousands of yards as opposed to units commonly used to measure similar distances.

Good faith efforts at providing conversions often use too many significant figures. The high velocity of naval artillery in comparison to high-trajectory artillery designed for land warfare gives a significantly different dispersion pattern to fall of shot. Naval weapons are much more accurate in deflection than range. That is why corrections are commonly made in hundreds of yards when few targets are that large. Naval artillery can safely fire on targets to the right or left of a friendly infantry position, but shell dispersion is unacceptable for targets between the firing ship and the friendly forces or beyond friendly forces. I suggest whole kilometers provide a meaningful comparison of range, while use of yards and meters implies unrealistic precision.

This subject might be better explored in one of the interest group forums. A related issue of precision is the comparative diameter of artillery barrels. Different conventions for rifling depth and groove-to-groove or land-to-land measurement of bore diameter, coupled with bore erosion and thermal expansion coefficients generally limit meaningful international comparison to two significant figures; although three significant figures may be appropriate when comparing artillery of similar type.Thewellman (talk) 17:40, 17 January 2010 (UTC)