Need information about M2 50

[Rex Tyson]

Looking at buying a MA Deuce. The manufacturer of this item is listed as  “AMA AC Spark plug”.  What or who is AMA or is this an original gun? The guy has owned it for 30 years.  I’m under the impression it is original AC gun?  We all know how some of these were papered. Any help is appreciated.  
 

Thanks 

Rex 

[johnsonlmg41]

quite likely the original registrant's initials.  Back in the day when registering something atf/treasury advised putting your initials as part of the serial # vs. creating an entirely new #.  I have a number of guns done this way.   Most are in back, but some are in front of the original number.   Putting additional numbers would confuse most people/ agents especially on guns where the numbers appear more than once.

[Mark2]

A FOIA Request will probably be the only way to determine how and when it entered the NFA Registry 

Edited February 21 by Mark2

[MPFiveO]

Do you have a pic of the receiver markings?

[GUNBUGS]

My only concern would be if it is a cut and rewelded sideplate. The original registration would tell the tale, as well as clear photos of the right side of the gun.

[Rex Tyson]

So I finally got some more information.  It is stamped on the bottom of the side plate like some other guns I have owned. 
“AMA , Roseville Ca” along with the serial number.  The RSP reads

“ Serial No . 1L4095

 1953  (a couple of stampings)

Machinegun 50-M3-AC-Basic”

Is anyone familiar with this name? I’m not clear why the form reads AC Sparkplug? 

thanks for your help  

Rex

 

[GUNBUGS]

I don't believe that's an AC Sparkplug gun. The sideplate markings are incorrect. AC quit production in May of '45, and the serial number doesn't fit into any AC contracts. Semper Fi Fifty by Iannamico and Goldsmith, page 133 gives the assigned serial numbers to AC. That isn't an AC number. Don't know who AMA is, but they are the folks that put that gun together, I'm pretty sure.

Edited February 25 by GUNBUGS
More opinion

[Rex Tyson]

56 minutes ago, GUNBUGS said:

I don't believe that's an AC Sparkplug gun. The sideplate markings are incorrect. AC quit production in May of '45, and the serial number doesn't fit into any AC contracts. Semper Fi Fifty by Iannamico and Goldsmith, page 133 gives the assigned serial numbers to AC. That isn't an AC number. Don't know who AMA is, but they are the folks that put that gun together, I'm pretty sure.

Agreed.  It was more apparent once I got more information. I was hoping someone might know AMA. The owner says Terry Williams and himself went through this gun at Ramo.  Maybe these parts were originally AC? Either way it’s a really nice well put together gun.  

[MPFiveO]

You're really going to need to do a FOIA on that one. My guess as to why AC Sparkplug is listed on the form is that the parts kit came from a AC Sparkplug gun. That information should have been listed in block H if at all.

I would also tend to believe that AMA Roseville CA is who actually built the gun and where. The when would only be determined by the original Form 2.  Interesting that it's stamped on the bottom of the sideplate.

Doing a quick search I believe I found the original manufacturer to be American Marksman Armory in Roseville CA. There's an M60 that was listed by Rock Island Auction with the same manufacturer name. There's also a Cobray M10 listed on the Gun Auction site with that manufacturer name as well. Maybe more searching will turn something up or someone who was around back in the day might remember them.

I have a RAMO M2 that was assembled by Nick Hope of RCGS in 1997 using an AC Sparkplug kit. It's been running flawlessly for decades. All three made good stuff.

[Rex Tyson]

On 2/24/2026 at 11:39 PM, MPFiveO said:

 I found the original manufacturer to be American Marksman Armory in Roseville CA. 

Thanks for that find. I never saw it in my search.