So I have the chance to buy one.  Heres the good, the gun is correct in every way, stampings are correct for an early US&S, all the parts match, and its not been rearsenaled that I can tell.  The price is low, $400.  I took a glance and when he said 4 bills, I said sold.  We he-hawed around a bit, and then I noticed the way the light was hitting the slide.  So heres the bad.  It looks like the slide is cracked.  I took a couple pics.  Should I still grab it?  Is it safe, or will have to find another slide to shoot it.  I've itching bad for a 1911 and I figured this was chance to hit a homerun.  What you guys think?

Take it... WW2 1911s are at a very high price these days... keep the original slide and find a replacement slide (Colt, Remington Rand) to shoot. Just my 2 cents.

It's still a home run. You can find another  USS slide for three or four hundred without too much trouble.   US&S 1911s are pretty collectible.
I wouldn't shoot it with that slide though.

Where is the dinner pic at home with your new US&S?  Any USGI complete receiver should be worth around $400.  That ain't no ordinary frame.

As suggested, I'd get a replacement slide to enjoy shooting it while you hunt for a possible correct replacement...  That should keep you occupied for the next several decades or so.

Looks more like a welded slide. Slide made from two demilled pieces.

$400 is still a good deal as the frame looks good.

US&S are the second rarest 1911A1. If you can get it cheap enough to restore.. go for it!

Welded actually did cross my mind, because the finish seems different out towards the muzzle.  You guys have convinced me to go back and get it tomorrow

Kind of looks welded to me also - as others stated for $400 take it! You can't go wrong

You can RCD in a circle acceptance mark. It's a US&S frame.

Went back and got it today.  I've been reading ever scrap of info I could get my hands on this afternoon.  The frame does have the correct RCD in a circle mark in front of the grips.  It is also correctly missing the P proof marks, since the serial number is low for a US&S at 1049XXX.  The mag release, slide catch, hammer, and backstrap have the correct checkering.  I see no way the frame is anything but authentic US&S.  The barrel is marked SP, for Springfield, and the earlier US&S guns were built with SP barrels, so that is possibly the original barrel, hard to say but the wear does seem to match the wear of the rest of the gun.  

Now that damn slide.  I got it apart today, what I thought was a different finish towards the muzzle is just the standard heat treatment that was applied to the slides after 1926.  This crack or whatever it is is only on the right side of the slide, the top and left side are flawless.  Looking inside the slide doesn't reveal much either, except that I don't think its a weldup job.  The signs of weld and refinish job just aren't there.  The crack follows the edge of the heat treated area almost perfectly.  If I ever find somebody local to me that really knows these guns I gonna have it looked at.  Thanks again guys

Nice pickup. Congrats. Take the slide to a machine shop and have it magnafluxed. That is a NDI that will tell you if it's a crack or just an imperfection in the forging.

I think you did good!  

Doesnt look like a crack looks too wide. I would think a crack would have to be hairline and hard to see. It looks so big you would be able to tell it is broke.

I don't  think I would shoot it like that even if it wasnt cracked because it could break there.

After googling "1911 cracked slide" for hours on end, I've yet to see a picture of any else's slide broke in a similar location.  Don't know if that means anything at all, but I guess its something

Not  a crack, looks more like demilled and welded. Real way to tell is look on the inside of the slide. Whats it look like there?