star wars - Why was Han Solo acting like he’s never seen Chewbacca’s bowcaster before?

In “The Force Awakens” Han Solo, Chewbacca and Finn are caught in a battle on the planet Takodana—where Maz Kanata lives, hangs out and does whatever she does—and Chewbacca begins using his bowcaster to pick off Stormtroopers like flies. At one point in the middle of the battle, Han Solo asks to try the bowcaster out and exclaims something along the lines of, “I like this thing!”

Okay, okay… Han Solo likes that big, bad powerful bowcaster… But why is he so surprised and delighted by its power and handling apparently only now in this film? Hasn’t Chewbacca had that bowcaster for at least 30 years? And within those 30 years you are telling me Han Solo has never put his hands on that bowcaster before? Or witnessed its power in action? Really? The first time he’s touched it is during the events in this film?

What is the in-universe explanation for this?

I mean I know some couples are shockingly oblivious to the things their partners have, use, do and have done. But this seems a bit of a stretch coming from someone like Han Solo who seems to spend endless days/nights with his Wookiee sidekick getting into all kinds of wacky action/adventure predicaments.

Answer

In the now-Legends EU continuity, Chewbacca was constantly tinkering with his bowcasters. That's right - bowcasters, as in plural. He owned several, and liked to upgrade and customize them. Both Han and Chewie's wife Mala comment on this hobby during his memorial service on Kashyyyk. Here's an excerpt from the New Jedi Order novel Agents of Chaos I - Hero's Trial:

Han's brows knitted. He set the box down on the stool and unlatched its finely wrought metal clasp. Inside, snug in a bed of cushioning material was a beautifully carved bowcaster, its marked and blemished skeleton stock polished to a deep brown gleam. An artfully disguised magnetic accelerator, the weapon propelled explosive quarrels at extremely high speeds. This one was equipped with a sighting scope and a recocking mechanism few human hands would be capable of operating.

"I recognize this," Han said, nodding. He compressed his lips to trap a moan fighting to escape him. "It's one of the first I ever saw him make."

Malla hooted. [Chewbacca fashioned it shortly after we married - while you were here. He fashioned better versions in his time, but this one retains the warmth and power of him.]

If this detail has carried over into the new continuity, then it's entirely possible that Han has never used this particular bowcaster.