My mod uses all the vanilla PZ guns almost as they are, with some tweaks to their statistics. The loudness of gunshots is one of the things I had to fix. In vanilla PZ you can fire off a .38 special and it attracts zombies only a little bit more than a running generator does. Not with my mod. Every gun is louder, but not excessively so.
I've renamed every weapon. The "M9" is the Beretta M92F, the "M16 Assault Rifle" is the M16A2, the "JS-2000 Shotgun" is the Remington M870, etc. Also the M14 is chambered in 7.62x51 instead of .308
I've also re-written some of the loot tables. It never made sense to me that the military in PZ wouldn't be issued any other handgun than the Colt M1911, when the Beretta M92F was their primary sidearm.
One thing that I always found frustrating especially with fully automatic guns is how suddenly they would lose condition. Sometimes it takes only one magazine's worth of shots fired and you'd notice that your perfectly mint condition gun is now at 85%. That shouldn't happen with my mod, since every single firearm has at least triple their original maximum condition, and the chance of them losing condition per round fired is also much smaller.
I've given all guns and attachments helpful little tooltips that explain what they are or what they do. Guns let you know their caliber of ammunition and whether they're semi-automatic, select-fire, etc, and attachments let you know exactly what they do. Magazines that are used by more than one type of gun also tell you which guns accept them.
Another thing that's a bit different is that if your character has never in their lives even held a firearm (Aiming 0), their accuracy with especially pistols and more "advanced" types of guns will reflect that experience level. Shotguns and especially sawn-off shotguns are your best option to level up your Aiming, because they are much more forgiving to unskilled shooters than a handgun would be for example. Once you get your character to Aiming 5, all the guns will be accurate. Especially if you use some of the attachments that improve accuracy. Aiming 6 and above will start turning your character into John Wick.
I've rewritten the maximum range for guns as well. I noticed that if a mod gives a gun an excessively long range along with high bonuses from the Aiming skill, trying to hit zombies near you with a long ranged gun becomes frustrating. I've so many times fired half a magazine and kept hitting zombies that aren't even in drawing distance, instead of the ones directly in front of me. In this mod the starting maximum ranges are higher than vanilla PZ, but not by much. Leveling your Aiming still gives bonuses to maximum range until that is fixed in B42, and you will gain slightly higher maximum range when using shotguns too.
The spread of sawn-off shotguns is also tightened from vanilla PZ. No more targeting and hitting an entire room with a shotgun just because the barrel is a bit shorter.

You can add or remove a gun attachment while walking. Running will still interrupt it. Your character also equips a weapon you attach something to or remove an attachment from.

The vanilla PZ "Iron Sight" is now a Fiber Optic Sight that's attacheable to any and every gun. It slightly increases accuracy and maximum range. It's a tiny attachment with tiny bonuses so the model is also tiny. I might make the model a bit better looking at some point.
In addition to the Red Dot Sight which I've made 2x as effective as the Fiber Optic Sight, there is now a special military-issue only SOCOM Red Dot Sight, which is 3x as effective as the Fiber Optic Sight. What guns accept a Red Dot has also been limited, and the SOCOM Red Dot only goes on military grade guns.
Laser Sights are now better at improving accuracy. I also made the laser itself a lot smaller. You can still see it if you zoom in all the way.
I never liked the x2 Scope, so it's gone. In its place is now the x4-x12 Scope, which increases minimum range slightly and maximum range quite a lot.
Another attachment I never liked was the "Choke Tube - Improved". Why would I ever "upgrade" my shotgun with an attachment that makes it do less damage? So it's gone, and in its place is the Double Barrel Choke Tube. I've also made it so that even if you saw off the barrel(s) of your shotgun, you can still attach Choke Tubes to them.
Since rifles have their Ammo Straps, shotguns can be upgraded with a Shellholder which increases reloading speed.
The "Recoil Pad" is now an Improved Recoil Pad, and it can be attached to shotguns as well. Rifles have a rare Marksman's Recoil Pad, which is 4x as effective.
Since rifles and shotguns have their recoil-related attachments, pistols have a Compensator, which will reduce recoil and give a tiny bonus to accuracy.
I had to re-categorize some of the attachments, but that will have no impact ingame other than if you pay really close attention, some detail in some text might seem weird to you.

I've always thought that suppressors are extremely important in a game like PZ, and that's why I still enjoy using the Firearms B41 mod. Even though real world suppressors aren't the movie/video game "silencers", I understand the importance of having a somewhat "silenced" weapon in a game like PZ, so my suppressors do act very much like the typical movie/video game silencer.
There are five types of suppressors for the different caliber weapons that are used. One for 9mm, one for .45 ACP, one that works with .223, 5.56 and 7.62x39, one that works with both .308 and 7.62x51, and even one for Shotguns. Their effectiveness is set so that the lower caliber guns will be more quiet than the higher caliber ones. You will still make some noise when firing a suppressed weapon, but it's at a sound level of ~30% of what the gun normally makes. In PZ terms, my suppressors make your guns attract zombies at around the noise radius of a slightly louder running generator. Not much louder than using a melee weapon.
Shotgun suppressors however are not nearly as effective for balance reasons. Shotguns in PZ are very overpowered just by their nature, so there won't be a "silenced" shotgun in my mod. It will still be better to attract only two thirds of the attention you would if you didn't have a suppressor, if you choose a suppressor over a choke tube.
My suppressors are rare, but not impossible to find. They do not spawn at police stations.

Short demonstration of how a suppressed 9mm will still attract nearby zombies, but not at all like an unsuppressed 9mm will:

7.62x39mm and 7.62x51mm NATO. I've added the crafting recipe with which you can conveniently "convert" your 7.62x51 rounds into .308s or vice versa. You can do the same thing with the 5.56 and the .223 rounds as well. Converting large amounts of ammo takes some time, so do it when you can and not when you have to. Not entirely realistic but eh, neither are zombies.

The Military Backpack is the one bag we all are always happy to find, not only because of its capacity but its weight reduction of 87% too. I've created 2 types of wearable "ammo bags", that share the Military Backpack's weight reduction. All three can be worn at the same time. They can be found at military surplus stores and military crates, lockers, etc. They spawn into the world either in green camo or plain dark grey.

A front-worn "Fanny Pack" consisting of three pouches you can stuff with your magazines and loose shells.

A back-worn "Satchel". About the size of the PZ Satchel but as good with weight reduction as the Military Backpack. Inspired by the Satchel With Bags mod.


9mm semi-automatic pistol with a 17-round magazine. Police and gunstore firearm.
.45 ACP semi-automatic pistol with a 12-round magazine. Police and gunstore firearm.
.45 ACP semi-automatic pistol with a 12-round magazine. Military and gunstore firearm. The only pistol that accepts both the Red Dot Sight and the SOCOM Red Dot Sight.

An iconic .44 Magnum. Police and gunstore firearm. "Do I feel lucky? Well, do ya... Punk?"

12 gauge semi-automatic shotgun with a 4-shell capacity. Police and gunstore firearm.
12 gauge pump-action shotgun with an 8-shell capacity. Military and police firearm.
12 gauge auto shotgun with a 20-shell drum magazine. Military only firearm. The only shotgun that can spawn with a pre-attached suppressor.
12 gauge holster-carried lever action shotgun with a 6-shell capacity. Rare find in bars and in the backrooms/lockers of gunstores. Kicks like a mule because someone has sawn off both the barrel and the stock. "Come with me if you want to live."
12 gauge semi-automatic combat shotgun with an 8-shell capacity. Police only firearm.

7.62x39 semi-automatic carbine rifle with a 10-round capacity. Gunstore only firearm.
7.62x39 select-fire assault rifle with a 30-round magazine. Gunstore only firearm.
7.62x39 select-fire assault rifle with a 30-round magazine. Gunstore only firearm. A more modern take on the classic Kalashnikov.

5.56 semi-automatic carbine rifle with a 30-round STANAG magazine. Police and gunstore firearm.
5.56 select-fire assault rifle with a 30-round STANAG magazine. Just a touch worse than the M16A2. Military only firearm.
5.56 select-fire carbine rifle with a 30-round STANAG magazine. Military only firearm. The only 5.56 rifle that can spawn with a pre-attached suppressor and the SOCOM Red Dot Sight.

7.62x51 select-fire battle rifle with a 20-round magazine. Military only firearm. The only 7.62x51 rifle that can spawn with a pre-attached suppressor and the SOCOM Red Dot Sight.

.44 Magnum lever action rifle with a 10-round capacity. Gunstore only firearm.
7.62x51 bolt action sniper rifle with a 5-round capacity. Military only firearm. Can spawn with a pre-attached suppressor.

9mm submachine gun with a 30-round magazine. Police, military and gunstore firearm.
9mm holster-carried submachine gun with a 30-round magazine. Gunstore only firearm.
.45 ACP holster-carried submachine gun with a 30-round magazine. Gunstore only firearm.

7.62x51 machine gun with a 100-round box magazine. Military only firearm. Weight restricts running speed and firing slowly drains Endurance.
5.56 light machine gun with a 100-round box magazine. Military only firearm. Weight restricts running speed and firing slowly drains Endurance.

I also added a Gun Cleaning Kit. It can be used 5 times to repair your firearms.

Police zombies can spawn with more than just the normal pump action shotgun. They can have an AR-15, a double barrel shotgun, a Remington M11-87, an MP5, the Mossberg M590 Tactical, or the SPAS-12 as well. In their holsters you may find a Glock 17, a H&K USP M45, or if one of them happened to be a Dirty Harry fan, the S&W M29 revolver.
Military zombies can spawn with a firearm.
Other zombies that in my opinion should have guns can also spawn with guns, such as bandits, hunters, etc.

All my guns can also spawn in survivor houses, and some of the rarer ones can spawn in those hidden loot stashes.

Those pesky pawn shop owners may also have been hiding away some not entirely legal stuff before the world ended. As with my other mod, be vigilant when looting.

More Simple Traits: Pick a Trait that gives you at least Aiming and Reloading 1, so that it's not such a massive headache to level those skills.
Better Gun Jam and Mod Options: I've nuked the jam chances of my guns by a lot, but vanilla PZ's jamming code is still ridiculously bad. Using these two mods together, you'll be able to set at which condition my guns start jamming, or if they ever jam at all. I like the setting of 70% myself.
Fort Redstone: Without this awesome map mod, you very well may end up not finding every single military-issue attachment/bag/gun during a Single Player run or if you don't have loot respawns turned on in Multiplayer. If you manage to break into the Fort and survive its hordes, it's an especially good place to find some maximum firepower. Those hangars don't store just outfits and tools *wink wink*.
Rain's Tools & Blades: Shameless self promotion here, but you will not regret having the option to wear a hatchet, one of my three machetes or even a wakizashi on your belt while carrying an automatic shotgun or a machine gun on your back.

This mod will be the backbone of my firearms/gun modding. I may add guns to it. I won't be adding stuff like bows/crossbows/miniguns to this mod. That's what a possible future sub mod is going to be for. I can always make sub mods such as "Rain's Firearms & Gun Parts - Extended" or "Rain's Firearms & Gun Parts - All in One", etc. Below is a (not complete) list of stuff I will be looking at for this mod. Help with any of this is much appreciated!
-Re-write how PZ determines some rooms. Because military crates anywhere can spawn military grade firearms, it's possible to find some of my military-only firearms in surplus stores, which is not intended. The way I was able to re-write the rooms and have it work was to overwrite the entire base PZ file, and there just has to be a better way to get this done. Meaning that my fix isn't in v1.0 so enjoy the highest end guns at surplus stores while you can.
-Give suppressors a Condition stat that can lead to a broken suppressor over time. If I can figure this one out, I can make suppressors far more common in the loot tables, as they will become something that you can't use forever. Also if I do manage to code this in, the gun cleaning kit will be useful in fixing suppressors too.
-No muzzle flash when firing a suppressed weapon.
-Make suppressor effectiveness something that can be edited via sandbox settings. For now, there's a helpful little comment in the code for anyone who wants their suppressors to be silencers that turn a firearm into a *pew pew* no-sound-at-all magic gun in their Single Player runs.
-Different magazine types. I have a framework for this but the lua part of it started kicking my butt and I ended up not trying to implement it for v1.0
-My handguns flip over when equipped and sitting down. I have no idea why, as it doesn't happen with my rifles/shotguns. Probably an XML thing I have to figure out at some point.
-New animations. Lever actions look like bolt actions until I dig into animating in PZ. I have no interest at all in learning about animating at this point, so this one will probably take a long time. Unless of course the Indie Stone implements their own lever action weapons in B42.
-Once gun lights become available at B42, I'll have to re-categorize some attachments. Unless the Indie Stone makes them occupy a different slot they do at the moment.
-Make the military packs & pouches spawn rarely on military zombies, and reduce their spawn rate accordingly in the loot tables. Something about the way I got this to "work" also doesn't work as intended.
-My Military Pack & Pouches are static clothing models instead of skinned (which is the normal thing to do when making new bags). I still haven't seen them do anything weird when worn with other clothing, so this may or may not get "fixed". If they turn out to cause serious visual issues with other new clothing stuff, I'll give a closer look to what the real difference between skinned and static is.
-I am fully aware of how fugly my models & textures are especially when closely looked at, at full scale. The model I spent most time on was the M60, because I wanted to see if I even could make an M60 model that looks as cool as it does in other gun mods. I am still learning 3D modeling, and I still know next to nothing about texture wrapping. Bear with me on those. Lucky for me, PZ scales guns, melee weapons and clothing items down to 1/100th of their actual size.