I have seen pictures of a regular m1a1 thompson with a longer barrel. Would it be possible to do this for the M1A1 by CYMA
GUNS: (ww2)
AGM sten mkII
Classic Army Colt 1911A1 GBB pistol
ARES PPSh-41
Deact Mosin M38
I guess so but why?
I think these long barrels are a modification to comply with some US states current gun law rather than a wartime thing.
aka Stigroadie
AFRA
better by design
"Truth is a shining goddess, always veiled, always distant, never wholly approachable, but worthy of all the devotion of which the human spirit is capable. "
ahh ok, I just thought that it looked like a mini BAR and pretty damn different
GUNS: (ww2)
AGM sten mkII
Classic Army Colt 1911A1 GBB pistol
ARES PPSh-41
Deact Mosin M38
I think these long barrels are a modification to comply with some US states current gun law rather than a wartime thing.
This is my understanding, too.
Some US states have laws against short-barrel guns with stocks.
AutoOrdnance/Kahr Arms currently make/sell semi-auto only versions with long barrels. The long barrels make them rifles under US law.
In a similar vein, they make short-barrel ("normal length") versions with no stock, meaning they are classified as pistols.
I think these long barrels are a modification to comply with some US states current gun law rather than a wartime thing.
This is my understanding, too.
Some US states have laws against short-barrel guns with stocks.
AutoOrdnance/Kahr Arms currently make/sell semi-auto only versions with long barrels. The long barrels make them rifles under US law.
In a similar vein, they make short-barrel ("normal length") versions with no stock, meaning they are classified as pistols.
I have realised that too. Have you seen the youtube video with that family firing the PPSh but the barrel had an extra hole in the heatshield 
GUNS: (ww2)
AGM sten mkII
Classic Army Colt 1911A1 GBB pistol
ARES PPSh-41
Deact Mosin M38
No.
And this sort of thing isn't limited to the US either: Before the handgun ban in the UK, semi-only MP5Ks were legal as the barrel length classified it as a pistol.
Or....
He could be talking about the period Long Barrel M1927 (not to be confused with the current production M1927A1 as mentioned ^above^ - they chose this model nomenclature due to it's similarities to the original M1927)...
Originally produced in both .45 semi-auto and .22 semi-auto for security/police force use, with the choice of an optional bipod.
NB, bizarrely, the ad above shows it being called the M1927 A-1? 
A Proud Member Of 'Team Spleen!' who play mainly at Gunman Airsoft, Tuddenham, Suffolk.
Not seen any pictures of these being carried by an military, but I may be mistaken!
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General James M. Gavin
CRY HAVOC AND LET LOOSE THE DOGS OF WAR
There was also a heavy barrelled version with a bipod for use as an LMG. Not very common either.
Cheers
Martin
"Mistakes in the initial deployment cannot be rectified" Helmuth von Moltke
Toys: AGM MP40, Cyma M1A1, TM M14/G43/SVT40, TM VSR/K98, SnS No. 4, ASG Sten, Ppsh.
Arnhem3,Gumrak,Campoleone
I've only seen 1 poor-quality photo of the "LMG". I thought it was just a one-off prototype, rather than "not very common".