Your bayonet started out as a P1913 and was made for the short lived Enfield P1913 rifle.  When the P13 rifles were re chambered to .303, they were called the P1914 rifle. Your bayonet fits both. The British did not rename the bayonet. It remained the P13 bayonet. The US made the P14 rifles for the Brits during WWI. The US contract was nearing the end, when the US entered the war in 1917. It was decided to keep making the P14, but re chambered it to 30.06. It was re named the US rifle Model of 1917...more commonly known as the US Enfield rifle. During the transition from British to US, the bayonets that were left over from the British contract, were simply used for the US Enfield.  At first, some of them had the British markings crossed out and had a US mark crudely stamped on it.  Your bayonet is a bit rare in that it as the expected P13 marks on the left side, but has the US marks with the ordnance bomb and eagle on the right side.  I cannot tell if the British marks were stamped over, or if the US markings were stamped on a "clean" ricasso.  The British marks would be a vertical string of the British Broad Arrow, a crown, a number, and finally an "A" which signifies American manufacture.  If you can't make out any hint of British markings on the right side, then it's pretty rare.  Even if the US markings are stamped over the British markings, then it's still fairly scarce. The scabbard is strictly British, and not issued to US troops (as far as I know).  Hope this helps. Marv

I don't know how I missed this but here is the patch that was on this uniform (Photo 1 & 2).  How do I know this will I just so happen to have photographs (Photo 3 thru 8) of one of his other uniform tops (Noland) with this patch sewn on the right shoulder which I missed while going through my reference material the first time around.  What is a little strange about this uniform is the name tape and USN tape appear to have been replaced.  It might have originally had the same type of tapes with the wider zig-zag sewing perimeters.  So if you can find this patch you can restore this uniform however this patch will be difficult to locate as they are scarce.   This was never UDT but during the Vietnam War UDT did work with IUWG.  

Definitely a possibility, asked an Army friend and he hadn't recognized it. I had found possibly the same site also. It is definitely a good copy if it is, it even has the surplus smell to it like all my other stuff that has tags. 

My guess would be that the bullet was slowed down enough to had penatrated this case and stopped before traveling all the way through.  Perhaps it hit a enbloc clip for a M1 Garand that slowed it's travel. Neat round, probably has an interesting story.

Unfortunately, it appears to be permanently closed....  

Beautiful patch.  

Thank you otter42, I think it's 30/06 but not sure. The headstamp doesn't say & I don't know enough to know from measurements. Your pic is awesome. I don't think it looks like a dummy round due to the dent and bent in metal vs cut away metal.

Thanks for the insight and info... much appreciated.  

Thank you eagle mtn, That scenario would explain the dents in the back side of the casing. But would the 30/06(maybe) have been belted in Vietnam? I also found some of these rounds in M1 clips (I think), but they were in a different box. Were M1's still being used in Vietnam? I'll see if the dent lines up with the lip of the clip.

Nope, it was just a image showing the face of it.