It varies. Unless you're going for tail cuts, you can use any weapon with the Part Breaker skill for good results. Bowguns, Hunting Horn, and Hammer can't really cut tails. Some bowguns have access to slicing shots, but after being nerfed a long time ago, I don't know how effective they are.

Since you're new to the series, be sure to ignore anyone that says a certain weapon type is bad. They don't know what they're talking about and as a long-time veteran I can assure you that whatever weapon type you choose, you'll do well with so long as you put in the time to learn it.

Every weapon is viable and effective. "Hit it til it dies, don't get hit."

Welcome fellow hunter!