At left, a lovely snap by Peter Gnanapragasm. From left to right: the .458 Lott, the .375 H&H and the .458 Winchester mag.
I have only the briefest of experience with the Lott. I've shot it a dozen times. I've never owned anything in such a fabulous wildcat cartridge.
The .375 H&H is a bread-and-butter round. It isn't my favorite for heavy work but I've used it. Treated properly, it'll down a T-Rex. It'll also get you killed if you're cavalier about its abilities.
The .458 Win Mag is an infamous round to me. I was too small and inexperienced when I first fell in love and now I can nearly clap my shoulder blades. It doesn't have the most wicked of recoils I've felt, but it is close (.338 custom Mauser claw-action on a Monte Carlo fiberglass stock that weighs barely 6 lb but should weigh 9 for this round. Killer recoil. Truly unpleasant).
These are just pictures. The business end is employing the bullet. Most of the time for your characters, using the bullet is only going to cause more trouble.
The problem with bullets is that they have a nasty tendency to cause less trouble than they should. In today's bigger is better market, I find this increasingly true.
Heavy rounds - pistol rounds - have limits. The inherent mass of a 230 grain ball ammo shell (the type used in .45 by the military) can go right through a fellow at under 10 yards and do little more than make him very angry for the next four steps as he stabs you in the head. The shell's own size makes it a problem. It can also - and frequently does - pick a victim up and throw him a good five feet back. It'll take an arm clean off it it hits a bone. From "clean through" to "hammer time" is a very big disparity for a single bullet.
Time and time again I read of close gunfights with he-man characters (mostly in newer writers) when the victims drop like ... well, like men shot with handguns on television. It is more interesting to the story when the gun doesn't do what the shooter thinks it should.
There is vast difference between being shot at in a gunfight on the street and hunting someone down in a structure. Being in a building with someone that knows what they're playing at and knows to wait quietly to kill you presents a challenge not faced by the vast majority of our troops - thankfully. It is however what our characters frequently see.
Marge shoots billy with a .38 S&W when he comes in the door. She gets off three shots. The first misses, the second hits, the third hits. Billy's down. Center of mass on the re-aim and the .38 was stopped by Billy's parts.
Mattie shoots Guy with a .45 ACP when he walks in the door. The full metal jacket slug goes through his gut and exits his back. She gets one shot before the recoil completely ruins her aim. Billy's back out the door falling down because the slug carried him. He ate about 275 of 300 lb. feet of force when the bullet decided he was dense enough to give up most of its momentum. He's never getting up again.
Gracie shoots Jim with a .40 S&W when he walks through the door. The bullet will go clear through Jim and stagger him a step. It's hot and keeps a great deal of its momentum in a regular full metal jacket form. Jim is on his feet - he's hurt but that hurt comes from tissue damage that will be more of a problem in five minutes than it is now. Gracie better be wearing track shoes or decide that a head shot is her best move. She's got about three tenths of a second before it'll be too late to use the gun again.
Now, the above scenarios are just guesses. Anything can happen with a pistol at close range. Get a rib and all the outcomes are vastly different. Get a hip and they're different again.
The point is: it isn't a sure thing. A shoot out with a pistol is not a sure thing at all. It'll be much more interesting if the victim doesn't drop like a third-season episode of "She's a sexy but serious detective and he's a quippy but soft-hearted jaded cop from the beat."
Give the victim a chance. Ask yourself at the murder, "what if?" Maybe, the victim scrawls "Rache" on the wall. Remember that one? ( Sherlock Holmes, "A Study in Scarlet," Sir Arthur Conan Doyle).
Maybe the victim grabs a tire-iron and kills the shooter. Now the victim gets in a car and drives off. That's a twist. Find the victim who fled the scene. is it a homicide? Maybe not. Maybe your detective has to go find the evidence in the form of a 2003 Pontiac someone pulled down a lane.
I'm full of ideas.
I better go write.