I’m trying to find out the value (maybe to sell) of a transferable H&R M16A1 that has only letters for a serial number.   The letters appear to be stamped over the numbers.  The previous owner stated that the gun was either a prototype or one of H&R’s armorers that built one as a special project and that is why it has the letters for a serial number.   I have not been able to confirm that story though.  
I don’t believe the gun is a re-weld.  I hoping to get it x-rayed next week to confirm that it hasn’t been re-welded.  
Any information would be helpful, thanks in advance.  

FOIA request to get its registration and transfer history.

Assuming it isn't a re-weld, and isn't US Property marked, then I think the key value consideration is going to be condition.  If the serial number work is clean, then I think an H&R factory MG would sell at a slight premium to a equivalent Colt factory MG.  Other than the SN, how is the gun marked?  M16?  M16A1?  If the gun is clean, well marked, and factory, then I think you are looking at 21K at the lower end and 24-25k at the upper end.  M16 market has cooled a bit recently, and if you want the H&R premium you have to find the person willing to pay for it so that could take a bit longer.  In my limited experience, H&R guns come up for sale very rarely and those I have seen have been US property marked.

It's a M16A1 and is marked "Property of U.S. Gov't".  It's in good condition and doesn't appear to be shot a lot.

With the US property mark then I think it is in the collector category and the upper end of the price range I quoted or possibly beyond -- I haven't seen enough of them for sale to have a good feel for how much one would go for.  X-raying it to be sure it isn't a re-weld would add a a buyer's confidence, but I suspect the customer for this gun will have quite a bit of knowledge on proper SN ranges etc. to know what they are getting.  Sounds like a very cool gun!

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Pics please!

The X-ray is the first step. Then it'll be figuring out if it was a test gun. It very well could be, they sold off all sorts of neat stuff from the museum back in the day.

If possible, take the pistol grip off the receiver and look for any stampings. Stemple marked his remanufactured guns on the grip boss. It's a pretty light stamp so look in really good light helps. Mine is marked on the left side.

I will try and get some pics up in the next few days when I'm off work.   When I get a chance I will pull the grip off and look for some markings.

Not all stemple rewelds are marked and if they were a lot could have been taken off. I've seen a few us property guns that were stemple remanufactures and no markings other than what is on the magwell.

I took the grip off and found no markings underneath it.  

I have a few pictures.  But I can't figure out how to post them.  

I should have the X-rays this week.

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Pictures added

Nice. Definitely not a reweld.

Actually looks like one of the H&R Museum guns I saw quite a few years ago.  The markings being filled in are are part of it, and if it looks like there was a re-rolling of the markings.  The real detailed part you need to show is the markings around the auto sear hole.  Most of the H&R contract guns had hard die rolled marks for most of the contract run, so the beginning and end of the die markings are deeper than the middle of the markings.

I dont think the serial numbers on those guns ever were published.  

Was that H&R found in an old collection in Northern Indiana by chance?  I know there was someone who used to buy a ton of stuff from Kent Lomont (Rest his soul), who was a few miles outside of Chicago.  Kent had a primo H&R M14 and M16 contract gun in his inventory back in the 1990's, but both of them went to this collector along with about 75+ other machineguns at one shot.

Nice piece if it is registered properly.  I have seen some of John Stemples later H&R rewelds that were that good, but all were marked on the receiver near the pistol grip tang or in the mag well rim (possibly done by someone else).   The give away is the markings around the selector side near the auto sear hole.

Looks like you have yourself a neat original OP.

Interesting, I see the "double circle" marking around the H&R logo and from the x-ray you have posted it does not appear to be a re-weld.

Are the identification markings filled with a yellow material, or is that chalk (used to show definition of the markings)?

Also interesting how the buttstock is marked with yellow stripes too.

Is the flash hider supposed to be a full birdcage or a three prong?

Thanks for the pics!

bird cage. the buttstock is something special. take a look over at autoweapons. the H&R he has has a DoD stamp on it, but the buttstock does not have the coloration that yours does.

That's a beaut!!

Interesting, I see the "double circle" marking around the H&R logo and from the x-ray you have posted it does not appear to be a re-weld.

Are the identification markings filled with a yellow material, or is that chalk (used to show definition of the markings)?  It appears that it's paint and not chalk

Also interesting how the buttstock is marked with yellow stripes too.  The yellow stripes are not paint, but rather like pin stripping
Is the flash hider supposed to be a full birdcage or a three prong? Unsure, that's how it came.  I would have thought it would have been a three prong.  I don't believe that the upper is original because the barrel has a "C" stamp

Thanks for the pics

IIRC, the GM Hydra and H&R's are all M16A1's built for the 1968 contracts because Colt's did not have sufficient production capacity.  Doesn't that mean a full bird cage FH is the correct one?

Interesting firearm, regardless.  Enjoy!