Need help preventing weapons' mods

Hello there,
I need to know about weapon mods
I host a server every couple of days for friends and online users
Some of the online users use cheats as wall hacks and shooting through walls
This is easy to find and figure out
The problem is with weapons .
As i understand, if i host a server with default files of the game or with ckr 1.1 these will be applied to all clients on the server, yet i find some online users enter the game with powerful weapon as overpowered machine guns or shotguns shooting from distance.
I searched online for client side weapon mods all i could find is skin mods for weapons
Does such files exist
I used to play mohaa in 2005 and there were such files for overpowered shotgun but i cant seem to find any now
Does this means these players cheat with other methods rather than .pk3 files?
Thanks

Theres nothing clientside will make machineguns overpower or shotguns shooting from distance.

The only thing exist is a no-recoil hack will make the weapons to shoot with more accuracy but you can fix that by enable the sv_recoilemulation to 1 if you have a reborn server.

I'm pretty sure about a client side shotgun pk3 file
Me and my friends used to play with it in 2005 but lan play not online
But i searched for it now and cannot find it .

ur not running the reborn patch... get that working first

You can't control that clientside.. so that has never existed.
You CAN get weapon skins of course, but only you will see them..

Any changes to weapons have to be made serverside, as the same damage, range, ammo, skins etc. are applied to everyone.
This also means that there are no cheats that change the power, range, damage or ammo of a weapon. The best a cheat could do is remove recoil (which will increase their accuracy) or simply put an aimbot on, which basically never makes them miss.
But all that is still with the same damage, range, power etc. that is set by the server.