Seasoning the pan (gun) for accuracy?

While shooting my new to me S&W 617 I noticed that accuracy improved dramatically after firing about 20 rounds.  The gun had just been cleaned beforehand.  This has never happened before with any of my other guns, at least not that I was able to notice.  Is it possible that a gun requires seasoning or shooting a few rounds through it before reaching its accuracy potential?  If so, is this true with all guns?

I've found it to be true. All barrels are different. The only way to know is to test.

some require it some don't, most 45s with kart barrels shoot best after only a few shots, but I had a 208s 22 that need a whole box before it got back after cleaning and many 22s are like that which is why many including me never do a true cleaning of the bore.