The basic information is there are three basic styles of stock:
Let' start gun by gun.
The first SPAS-12 came with either a folding
metal stock with hook or a detachable wooden stock.:
See Folding Stock Versions below.
The wooden stock detached:
That is "detached" as in with a screwdriver and an allen wrench, it does not pop off.
Early on at some point the wooden stock
was replaced by a one-piece synthetic stock:
I have also read that at one time "Choate made a skeletonized plastic stock which some, especially those who find the SPAS-12 factory pistol grip too large, will find more comfortable."
The LAW12 manual we have indicates it normally
came with the detachable wooden stock previously offered on the early SPAS12:
The manual also said
a folding metal stock was available as an option, but I've not seen one:
Note that this is not identical to the SPAS12 stock, it does not latch to the rear site like the original SPAS12 stock does. I've seen a few like these on SPAS12's. See Folding Stock Versions. A SPAS12 metal stock will NOT fit your LAW12.
The SAS12 originally came with the same
detachable wooden stock:
I have seen some at a gun show that used the one-piece synthetic stock shown above on the SAS12.
A SPAS12 metal stock will NOT fit your
Tim, a reader off this site, was curious if it was legal to go put a folding stock on a SPAS that didn't come from the factory with one. The law on this subject is very confusing, I read it once and only had more questions.
He researched this and writes:
"Here is a letter from the BATF concerning SemiAuto Shotguns, and the Ban: http://www-2.cs.cmu.edu/afs/cs/user/wbardwel/public/nfalist/atf_letter87.txt
Basically, this means that it is LEGAL to take a post 89 or 94 SPAS (Fixed stock, 5 rd magazine), and add a folding stock.
You still can't legally
add the mag extension, however -- maybe."
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