yes

Wonder why the firearms only have one gem imprint on them

POW POW go brr

For a pure gun build in PVE, use both Repeater and Evelyn (with Reiterpallasch in the right hand, of course). Start fights with Repeater and use Bone Marrow shots for the insane damage output. Once you're out of BMA, switch to the Evelyn. You get more sustain out of it, and can spam away with your blood bullets without wasting that last shot.

All the other kids with the pumped up kicks
You better run, better run, outrun my gun
All the other kids with the pumped up kicks
You better run, better run faster than my bullet
All the other kids with the pumped up kicks
You better run, better run, outrun my gun
All the other kids with the pumped up kicks
You better run, better run faster than my bullet

I've always used Evelyn as my primary firearm.

From my personal experience of putting 1500 hours into this game. This weapon is amazing at parries 6 to 8 feet between your target. Evelyn wasn't built to be CQ. Because of its range and accuracy, it takes pride in keeping an average distance between the player. It's made for picking people off and setting up viscerals. Also, its great against bosses whom can be parried. I recommend you use this against Kos. I was able to prevent his second phase by spamming viscerals.

P.S Great Velocity

Why actually be good at the game when you can spam this trash?

I've 1 hit a guy with a +10 evelyn with 40 bloodtinge at lvl 64. Bone marrow ash + a 30% blood attack gem is just beautiful. ~750 damage. ALWAYS level vitality first boys.

"I can't parry but I can spam 24/7 like a CoD/BF/any other shooter *"

I think people are a little too quick to call this the best firearm in the game. The Hunter pistol outdamages it if bloodtinge is 20 or below. The repeating pistol outdamages it at every level, but costs an extra bullet to fire. If you are using a pistol with high BT, you likely want a gun that does as much damage as possible, which is the repeating pistol. I very rarely use all 20 bullets unless I'm using a cannon. Every other enemy drops bullets, you can get two different formless oeden runes very early in the game, and bullets are cheap to buy; blood bullets also help. The Evelyn takes the longest to obtain from the start, and it has that weird long-barrel weakness. All I'm saying is that some arguments can certainly be made against this weapons favor.