My Grandfather taught me not to go off 1/2 cocked, wait a few days, Think things thru and then go off FULL cocked. Rob63 is absolutely right and I stand corrected. Frank did a fantastic job in putting together the research for the SSR but it is far from a complete record. On 3 occasions I had the opportunity to do serial # research at the NA when stationed in DC. I'm going to try and find the copies of the microfilm I copied and post it but that was a long time ago. I saw many examples where gun lots were issued and the ordnance officer doing the recording would just do the first line and then either draw a line straight down each column to the next lot, some times they would write the serial numbers and draw lines for the Company and Regiment etc. Some of these Frank did not record that way if at all and has always stated that it's not a complete record.
There have always been discussions about this and I guess what I'm getting at is the SSR would be like the Readers Digest condensed version of a book and the National Archives THE book. The article below explains a lot about this process.
Firearms Genealogy
The Impossible Takes Longer
By Michael P. Musick
The information most sought after in ordnance records is data on the issuance of arms by serial number. Those familiar with twentieth-century records often assume that official records of some kind will enable the possessor of a particular Colt percussion Army Model 1860 revolver (for example) to learn the name and unit of the person who received serial number 120055. That is not true— at least, not entirely true.
No series listing serial numbers of Civil War - era weapons were among the records of the Office of the Chief of Ordnance when those records were transferred to the National Archives. It is not possible for the Archives to locate a record by serial number for any weapon of any type. However, the intensity of desire, coupled with the willingness to spend countless hours personally searching, can accomplish the seemingly impossible.
Scattered few and far between among the bound unit records of some Union volunteer cavalry and artillery units (RG 94, entries 113 and 114) in the records of the Adjutant General's Office (not the Ordnance Office) are occasional lists by serial number of pistols and carbines. No inventory or other finding aid states that fact; it is not apparent from a casual scanning of the records; and there is no index or list that will disclose where such things will be found.
One or two private researchers, with prodigious patience and dedication, have systematically searched through hundreds of these volumes and compiled a number of lists of serial numbers that now and then enable a proud possessor to say (for example) that Colt number 120055 was issued to Sgt. John F. Peters of Company L, First Connecticut Cavalry, in 1863.
Frequently the lists of serial numbers will not identify the make or model of the arm, only the type (pistol or carbine). Other sources, such as Summary Statements of Quarterly Returns of Ordnance and Ordnance Stores on Hand in Regular and Volunteer Army Organizations, 1862 - 1867, 1870 - 1876 (National Archives Microfilm Publication M1281), must be consulted for that additional information. Other arms or equipment, such as swords, saddles, cannon, or muskets, are not traceable in this way. No comparable Confederate lists are known. Moreover, the side arms of commissioned infantry officers are not shown. The latter can be sometimes be found in the privately held records of the companies involved, such as the Firearms Division of Colt Industries in Hartford, Connecticut.
One assiduous private researcher has published lists of serial numbers, including some for the Civil War. Beginning in 1983, Franklin B. Mallory, under the designation Springfield Research Service (P.O. Box 4181, Silver Spring, MD 20904), has issued these lists showing the units that received specific arms. For a nominal fee, Mr. Mallory has been providing the names and units of soldiers whose weapons appear on his lists. The arms listed are only a small fraction of the total issued during the war, but for a handful of fortunate souls, a hitherto impossible feat of identification becomes possible.