Speer manufactures 9mm Luger and 380 Auto brass cases in two variations identified by dots before and after the brand name, or the absence of those dots, in the headstamp. Mainly a difference in weight, there are other subtle differences and, of course, some exceptions.
I. 9mm Luger
A. Weight: The weight of Speer-manufactured dot SPEER dot/dot CCI dot/dot I dot/dot BLAZER dot-headstamped 9mm Luger cases averages 56 grains whereas Speer-manufactured (no-dot) SPEER/CCI/I/BLAZER-headstamped 9mm Luger cases average 60 grains. The base of the two-dot cases is also noticeably flat compared to the 60-grain variety which are concave to a degree, presumably because of manufacturing differences. Examples:
B. +P, +P+: All Speer-manufactured 9mm Luger +P and +P+ cases I have seen are the two-dot type. Nonetheless only the early flat base +P and +P+ cases are the 56-grain variety. Later concave base +P cases average 60 grains. Left two 56-gr flat base, right two 60-gr concave base.
C. FC: The Speer-manufactured dot FC dot- and FC-headstamped 9MM LUGER (upper case M’s) cases found in the WalMart boxes, are the 60-grain variety. There are, however, Speer-manufactured FC dot (single trailing dot) 9mm LUGER (lower case m’s) cases which average 56-grains. All these single trailing dot cases I’ve seen came in Independence-brand boxes with the Speer lot number A22T9 (22 January (my birthday!) 2012, line 9).
D. Aguila: I remembered I weighed dot AGUILA dot-headstamp cases years before and they, too, were 56 grains. I reweighed them and confirmed their 56-grain weight. They had to be older because they all had the old style two-legged primers. The newer standard AGUILA (over) 9mm cases average 60 grains. Both 56- and 60-grain varieties have flat bases. Heck of a coincidence – 56-gr two-dot and 60-gr no dot.
II. 380 Auto
A. Weight: The weight of Speer-manufactured 380 Auto brass cases averages 48 and 50.3 grains, with the dot SPEER dot/dot I dot/dot BLAZER dot/dot FEDERAL dot-headstamped cases being the 50.3-grain variety. The Speer manufactured (no-dot) SPEER/CCI/I/BLAZER/FEDERAL-headstamped cases are the 48-grain variety. I don’t have an example of a dot CCI dot (over) 380 AUTO case and FC (over) 380 AUTO cases are Federal-manufactured. The two-dot 380 Auto cases also have an interior shoulder like the CCI-headstamped non-reloadable ALUMINUM 380 Auto and 9mm Luger cases. The no-dot variety have no interior shoulder.
B. No Aguila connection in 380 Auto I’ve found. The few Aguila 380 Auto cases I have are not two-dot and weigh 46.3-grain (small letters) and 44.4-grain (medium letters).