Any problems with switching between Sig 226 standard and threaded barrels?

There would not be a problem just because one was threaded and one wasn’t.

Classic line SIG pistol barrels do, however, sometimes require minor fitting due to slight manufacturing variances. It’s unlikely that that would be required for a new barrel, but not impossible.

Thank you.You responded to the question that I failed to formulate properly! Thread was not my real concern. Need for fitting would be obvious upon insertion into slide - correct?

quote:

Originally posted by ihbwotrr:
Need for fitting would be obvious upon insertion into slide - correct?

Yes, it might need fitting if the slide does not go fully into battery when released at speed.

If, however, the new barrel is just tight, i.e., the slide hesitates when manually cycled, in my experience the solution is to just shoot the gun with the barrel and things usually just wear in naturally. I experienced that long ago when I wanted a P229 chambered for 357 SIG. The store (without saying anything to me) swapped a new 357 barrel into a 40 S&W gun. The slide was tight at first (a good thing, actually) until I fired a box or so of ammunition. And that might work even if the slide is released at speed and needs a little manual encouragement to go fully forward. I would try that before any actual fitting work.