Why does my M59 have a long bayonet slot?

[22srfun]

    I finally got around to cleaning all the cosmoline from the M59 I got back in 2015.
It is in very nice shape.
   Matching numbers on
Receiver
Bolt Carrier
Bolt
Cover
Stock
Trigger guard

  The bottom of barrel and receiver are marked J 193. And it has all the common part numbers.

  It has the 1.TRZ mark on the stock.

   The bayonet appears to be correct for the M59. But there are two odd things.

   The screw for the bayonet was severly damaged, like someone tried to get it out and gave up. You can see it in the picture. But I got the rifle right out of the crate from a dealer at a gun show, so did it happen in Yugoslavia?

   The screw head had flats on either side as if it had been squeezed in a vice. Has anyone seen this as a way to keep it tight?

  I was able to remove it and I repaired it as best as possible.

  But the stranger thing is that the stock has a slot for the bayonet that is long like a M59/66 stock.
It has an M59 metal butt plate with the normal cleaning kit cavity.

  And it has the round head cross bolt, not the flat head like a 59/66.

  Any thought on how this ended up with a 59 style stock and a 59/66 style bayonet slot?
 

[Greasemonkey]

Possibly being a later refurb, the stock may have been reconditioned, as shown by the TRZ stamp, and set up for use on a M59/66, could be a one slot fits all models and how it found it's way onto an M59.

The screw..... I got nothing, unless somewhere at some point, someone tried to pilfer the bayonet.   They are not the easiest thing to find.

[Phosphorus32]

Anything goes on a refurbished Yugoslavian.

[echo1]

Could it possibly be a Paratrooper length bayo, making the slot appear longer? If so, I've got a standard length Chinese bayo I trade you for it. PAX

[Phosphorus32]

That’s a correct length and gray finish M59 bayonet.

[Justin Hell]

Interesting stock, the butt looks abnormally straight....I am curious about the buttplate that is in some photos and absent from the others. Was that added later? I suppose it could be the angle...

It looks very similar to my M59/66 stock...if you were to remove the rubber buttpad...with no visible tapering for a metal plate.  A typical M59 butt would have the slight 'lip' at the top to allow for the contour of the typical buttplate.  This one makes me wonder if someone put a flat plate from a laminated Russian on it? (Those lack the lip) I would lean to it being a 59/66 stock refurbed onto a 59.

The only stickler is the correct serial on the stock...and it's apparent age. Perhaps there was some crossover manufacture of both rifles and this got a stock that could have been used for either? 

My M59 has a flat crossbolt nut, my M59/66 has a rounded one, my M59/66A1 has a flat one.  The 59 got the TRZ treatment, The 59/66 isn't refurbed...while the 59/66A1 was new. IIRC the nut may be flat on the inside 'side' and rounded on the outside 'side'.  I had an odd Chinese stock with a flat nut once, when I needed the crossbolt from it, I found the inside side as it was installed was reversed.   Perhaps later on they realized less crud would accumulate if you put the round side in, and then refurbs got the flipped nut?  I hadn't really ever noticed that on mine until you mentioned it.