Two weeks ago I was shooting my Norinco 1911 and it locked up tight halfway through a mag.  After getting it apart, I noticed that the barrel link had broke, snapping on one side of the loop the slide stop goes through.  I ordered a Wilson link, the standard sized one (0.278", I think) and swapped it out today.  It looks and feels like it did before, but is there a function check I can do to verify the lockup is good before I test it with live ammo?

The barrel locks up in the slide?  The slide manually cycles and does not bind?  If yes test fire to see if it functions.

Link sizing on a 1911 is an exercise with multiple variables.

Ideally, you want a link that will  1) pull the barrel down clear of the upper slide lugs within the first .25" or so of rearward travel, 2) allow the barrel's feet to stop on the frame vertical impact surface, 3) be long enough to provide at least .040" of engagement with the upper lugs, 4) allow the slide stop pin to move freely along the lower lugs without bumping them.

Chances are that the original link failed because it was too short and it was stopping the barrel instead of the barrel feet hitting the VIS.   You can test this by removing the recoil spring, pulling out the slide stop and reinserting it but allowing it to hang down over the trigger guard area.  Pull the slide out of battery a bit and press the muzzle against a firm surface until it's as far back as it will go.  Then try to rotate the slide stop.   If it rotates freely, the link is not under tension.   If there is force being exerted on the link and it's difficult to rotate, you probably need to go to a longer link.

The risk you run with a longer link is that it will no longer pull the barrel down far enough, soon enough.  This can lead to battered upper lugs as the slide has to crash past the upper lugs on its way to the rear.   One way to check for this is to put a dowel in a vise, extending out to the side.  Put the dowel down the bore of the assembled pistol (you can leave out the recoil spring to make things easier), and press down with the pistol on the dowel.  This puts an upward pressure on the barrel.   Then try to pull the slide back.  The link should pull the barrel down against the upward pressure by the time the slide unlocks and begins to move back relative to the barrel.

As always well said way better than I could ever put it!

LOL... well, it's a Khyber Pass-ish way of checking link timing, but it should provide some idea of how the link is working.

Thank you, this is exactly what I was looking for.  I performed the first test you mentioned, it doesn't rotate freely but it can be moved with very little pressure.  I think there must be some contact, but not that much.

You may be OK.  There's no telling how long the original link was.  At any rate, if it breaks again after a few years, it's only a $5 replacement.

I picked the .278" link because that was supposed to be the standard size, I know I haven't fitted a new barrel or done any work to tighten it up and it appears the previous owner didn't do anything of the sort.  I'll shoot it tomorrow and if there's no obvious problems I'll call it good.