A guy at work came up to me and showed me pics an Israel made black 50ae barrel with 2 slots, 2 mags and case and told me to make an offer if I was interested.  Box says mark XIX.

I’m trying to put it on a USA made XIX 50ae DE in brushed nickel. Well, I bring it home to see if it fits and it won’t lock in with the lever.  My original barrel is fine with zero issues. It seems to not got back far enough to clear the locking mechanism.

Are these not interchangeable? Internet says they will.  ??

What’s going on here?

I’d love to counterbore/thread it for a suppressor.  

I don't think the earlier 3/8" top rail variants had slots so yours should be 7/8" wide which is a XIX, it should go.

I'd start by measuring the rear base where it drops in and compare it to your original barrel.

Has the barrel ever been used? That may be why he wants to get rid of it.

The barrel has been used. It was part of a 44 mag/50ae set but I guess he sold it all without the 50ae stuff. I don’t know, the person seems rather odd.

When I set the barrel in place and side it back you can hear metal on metal but won’t lock in place.  The rear lower section of the barrel seems a hair different to mine.

I was hoping it was a simple answer, like the 2 aren’t interchangeable.  Guess I’ll have to measure everything out.

I low balled them and I guess I’ll take a chance.

Email sent.