Interesting!
Mine has those attributes minus the individual numbered parts.
It however could have had them before I got it in hand.
I scored it BNIB/NOS but it went straight to the bench. I never seen or held it in its factory out of the box configuration.
I had it dehorned, S&A one piece mag well fit & blended, massaged & polished internally blah blah blah,
so its possible it was polished off if it existed.
Looks like sharpie on the slide lock. Im not an expert on MIM parts and pics are sometime deceiving,
Is that a MIM slide lock? Looks like I can see the mold lines and that dimpling sandpaper look.
If it is its of course not original to the pistol.
The numbers on the barrel look odd and not a font I am used to seeing on firearms.
I had the smith remove ALL the writing from the barrel on mine including the stupid warning about,
Caution: Exhaust Ports HOT Read Owners Manual or whatever it says.
If the barrel was numbered it was removed along with the rest of the writing and I never saw it. It only says SA .45 AUTO now.
Springfield told me it was built in April of 2000. They didnt have much more than that other than where it was sent to,
I dont remember that part.
The numbers dont match each other so I dont think they are of any significance IMO.
Does your barrel hood have the warning about the exhaust ports? If not it might not be original which might account for the #.
Any & all info you find I would surely like to know as well. Info on this pistol is quite elusive and far between.
When I bring the pistol up in forums looking for info most all I get is a lecture on why I chose .45 Super and why 10mm is what I should have.
Then the ballistics lesson follows & then everyone starts arguing calibers LOL
Makes me chuckle everytime!
Definitley interested in what you know/find out.
Thats all I got!

EDIT: FWIW the backside of my slide lock looks the same as the outside, flat smooth & polished.

Looks like this now...

 

Mine had some of that: The hex bit guide rod and the etched small parts, but the '.45 super' was rolled onto the left side of the slide. The barrel was electronically etched with '.450' instead of being stamped '.45 cal.' It is one of several guns that I wish I didn't have to sell.

 

I got rid of the hex guide rod, looks like this now.

The other side.

 

Looks great.

 

So, a barrel marked '.450' or 'Super .45' will shoot .45 ACP but the reverse is not true because of higher pressures with the .45 super and .450?

 

The barrels are the same. You can convert any 1911 to run .45 Super altho only all steel guns should be converted.
Cost less than a 100 bucks for the parts. Once converted you simply swap recoil springs.

This is my beater test pistol I put together when I was experimenting prior to the Springfield.
It has been converted to run both. My neighbor lady friend loves shootin this heavy old thing, shes 88 lol
She has a little 9mm SIG but she cant hit a bull in the a** with a banjo with it.
The dot thrills her to no end once she got the hang of it. She does shoot it from a rest.

 

Without more pictures of the pistol . Looks like an early version , that made a trip back to the Custom shop .
The last 3 of your serial number is 799 I'am thinking . You may want to call Springfield Custom shop and
check if it went back to them .

 

My V12 has the hex and hand cut #'s on many parts. It is a 45ACP though.

 

Your less than a 100 bucks and some fairly easy labor from .45 Super if your so inclined.
IMO its the easiest and cheapest way to step up your game a bit and stay in the .45 arena.
I could have went 10mm but I dont have anything else 10mm so it was a simple choice for me.
Have a lone gun in a lone caliber with separate mags or convert & simply swap recoil springs in pistols I already own.
Biggest thing is keeping the ammo separated because visually you cant tell the difference other than the stamp.
If you do get one mixed in (I have) you can tell lol
IMO .45 Super is much more pleasurable to shoot than 10mm and I dont feel like Im cheatin on JMB.

 

>SNIP<<

Does anyone know the significance of this?

It looks like a PO hack engraved the numbers. Perhaps he was an obsessive parts swapper to keep track of the OEM parts? Maybe he wanted to fabricate a RARE scam gun? I don't assign any significance to it.

 

I spoke to Springfield Custom Shop who informed me that my V was built in 1999 and was “one of the first ones ever made”. In the early days of production the V16 parts were numbered after being properly fitted to the weapon. This only lasted a few months after production of the V16’s began and was no longer necessary once they streamlined production. For anyone interested, here’s a couple pictures of my V-16’s. Currently I’m sitting on 2 mint condition (middle of the road rarity) V’s, and 1 of the much rarer “National Match” produced in 1999.

*The parts pictured are all original and definitely NO MIM!
I’d love to modify my slide with some clean lightening cuts but I can’t bring myself to do anything that could negatively impact the value considering how rare the weapon is.

 

Can you tell us what trigger and magwell you installed??

 

I own an early 2000 longslide that went back to SACS for custom shop Accurizing Package . Great pistol . Your pistols are very nice .

You can tell early Longslides because they have fixed front sights with no dove tail groove

 

All of the V16 Longslides are supplied with two springs and can shoot either 45 ACP or 45 Super. Ace Custom Guns sued Springfield for copyright infringement and Springfield changed it from 45 Super to 45 Cal. Mine says 45 Cal and I've put over 1000 rounds of 45 Super with it. These days I shoot Remington 45 ACP 230g bulk for practice and Buffalo Bore 255g hardcast at 1100 fps for reals.