As Herr Craig has shared, it is confusing and imprecise.
The 1840 survey/inventory was an attempt to clean up if not clean out the armories by prioritzing arms into classes, which looked at older arms that could be altered or converted, and arms considered so old they were junk and sold off at public auction. (However, it seems not universally done, as well as complicated by holding on to to lower class weapons deemed good enough for miitia and emergency use.)
I assume with the threat of war, another inventory was conducted and completed in December of 1859 listing the muskets and rifles in store. I, and others, have posted it several times over the years, and it should be archived in the SEARCH function.
Ideally, the armory/arsenal system divided them up into different classes often based on their major function as well. For example:
Little Rock armory was a "Class 3" armory - storing mostly older weapons intended for state militias if mobilization was called for. According to the Confederate inventory after the CS seizure these list:
5,625 M1816/22 Springfield muskets, flintlock
2,864 "Hall's" rifles, flintlock
52 M1816/22 Percussion conversion muskets
357 M1842 Springfield muskets
900 M1855 Springfield rifle- muskets
54 M1841 "Mississippi" rifles
Last but not least, we do not know the numbers due to "rate of usage" and the normal life expectancy or life span of an arm in service. Some numbers are always exiting due to use, loss, unmendable breakage, theft, etc.
In gleichem Schritt und Tritt, Curt Schmidt
Not a real Civil War reenactor, I only portray one on boards and fora.
I do not portray a Civil War soldier, I merely interpret one.