Around S/N 30,000 was the Pre-Ban cut-off, call to verify*

Bushmaster

Below L051000 - Assembled Pre-Ban Rifles
L051001-L063000 - Mixed Pre-Ban Assembled Rifles and Pre-Sept 94 Lowers
L063001 and Up - Post-Ban

Colt

CC001616 and Below - Pre-Ban
CH019500 and Below - Pre-Ban
GC018500 and Below - Pre-Ban
LH011326 and Below - Pre-Ban
MH086020 and Below - Pre-Ban
NL004800 and Below - Pre-Ban
SL027246 and Below - Pre-Ban
SP360200 and Below - Pre-Ban
ST038100 and Below - Pre-Ban
TA10100 and Below - Pre-Ban
BD000134 and Below - Pre-Ban
MT00001 and Above - Post-Ban
BK000001and Above - Post Ban (CAR-A3)
CST000001 and Above - Post-Ban (Began Late 1997 Production)
CMH000001 and Above - Post Ban

DPMS

Below 10300 - Pre-Ban. Some or all lowers are cast. Black in color. Some lowers are Stainless Steel.

Eagle Arms
Now called ArmaLite

They will not give out a list, but will look up on an individual basis.
Lower receiver serial numbers DO NOT begin with EA.

Essential Arms

All are Pre-Ban as they went out of business in 1993.
(DPMS bought them prior to the Ban)
Call DPMS Lower receiver serial numbers begin with EA.
Some or all lowers are cast. Light gray coloring.

J.L.M & Sons*

SC001 thru SC250 - Pre-Ban

Olympic Arms

4-numbers only - very very old. Probably machined from bar stock.
1-letter and 4# - older receiver, but forgings.
2-letters & 4# - most receivers follow this pattern.
2#, 2 letters, 4# - the first two #'s are year of manufacture of the lower.
2 letters, 6# (separated 2 & 4 - e.g. SA 96 0000) - first 2 #'s are year of manufacture.

There were some odd variations and some custom serial numbers mixed in thru the years also. And, some receivers manufactured after the ban have the year stamp after the model name, not in the serial #. And if you don't see a year stamp on the receiver, it is not necessarily pre-ban!

Read here for more information: www.olyarms.com/prepost.html

35222 and Below - Pre-Ban (Note:Some lowers are cast not forged.
Out of business)
Post-ban have a year prefix in the serial number.

BUSHMASTER

Quality Parts Co.
999 Roosevelt Trail
Windham, Maine 04062
Orders: 800-998-SWAT
Info: (207) 892-2005
Customer Service (207) 893-1426
Fax Orders: (207) 892-8068
www.bushmaster.com

COLT

Colt's Manufacturing Company Inc.
545 New Park Avenue
POBox 1868
Hartsford, CT 06144-1868

DPMS

http://www.dpmsinc.com/ Defense Procurement Manufacturing Services, Inc.
13983 Industry Avenue
Becker, MN 55308
Phone (612) 261-5600 or 1-800-578-3767
Fax (612) 261-5599
Email: dpms@dpmsinc.com
Web Site dpmsinc.com