Fire Arms vs Crossbows

We're starting a new campaign where I'm playing as a level 5 Ranger who will multi class into a rogue for the rest of the campaign.

I'm trying to pick my level 4 feat and I'm stuck between gunner and sharpshooter. I know Sharpshooter is great even with the 2024 nerf and works for all ranged weapons, but Gunner would give me access to fire arms, which my DM said were allowed. The best he'd allow me to use would be the hunting rifle, which does 2d10 damage compared to the heavy crossbow's 1d10, which keeps on par with a wizards 2d10 firebolt. Yes i'd get two attacks, but that would be my "cap" on basic damage compared to wizards getting fireball and more at later levels.

The real question I have is, is the added range of sharpshooter worth more than the ability to use fire arms? A crossbow has a 400 foot range, so I could stay well out of combat unlike with a hunting rifle, but I'd be doing significantly more damage with the fire arms. If I went Gunner, I'd still take sharpshooter later, but I don' know exactly when.

Looking for some thoughts on if the added range is worth it compared to a higher damage? None of this is taking into account crossbow expert for the bonus action attack, which I'd take later if I stick with sharpshooting crossbows fyi

Crossbow expert does not grant you a bonus action attack. That is a function of the Light property of the Crossbow, hand; crossbow expert just lets you add your ability score modifier to that bonus action attack if it is made with the Crossbow, hand.

One thing to note is that a Rifle, Hunting still has the Reload property, which will eat up your bonus actions. You won't have that problem with the Crossbow, Heavy. Depending on your build and strategy, this may or may not be a problem for you.

The second thing to keep in mind, is that the Longbow and Crossbow, Heavy each have the Heavy property, which means they could benefit from the Great Weapon Master feat. This brings the damage of those weapons up much closer to that of firearms. Let's make a comparison...

So at level 13, and assuming 20 Dexterity at that point, your gun would be doing 2d10+5 damage per shot, while the crossbow would be doing 1d10+10. That's an average damage of 16 for the gun and 15.5 for the crossbow. The crossbow will be more consistently average due to more of it's damage being static, but it takes two feats to get there (Crossbow Expert and Heavy Weapon Master). The rifle on the other hand will take less investment to get it's damage, but will be more variable with its damage range (7-25 vs 11-20), and eat up your bonus actions to reload. The rifle will have the potential for some really big critical hits as well, rolling a nice 4d10+5 when you score a critical hit.

Both options are comparable and have their pros and cons. It's up to you to decide which is right for your character.