#define ADDR_WeaponMgrPointer 0x2294530
#define M16 25
#define M4A1_S_Predator 1508

void DoWeaponReplace(DWORD currentweaponid, DWORD newweaponid)
{
DWORD CShell = (DWORD)GetModuleHandleA("CShell.dll");
DWORD pWeaponMgr = *(DWORD*)(CShell + ADDR_WeaponMgrPointer);
if(pWeaponMgr)
{
    DWORD currentweapon = pWeaponMgr + 4 * currentweaponid;
    DWORD newweapon = pWeaponMgr + 4 * newweaponid;
    if(currentweapon)
    {
        if(newweapon)
        {
            *(DWORD*)currentweapon = *(DWORD*)newweapon;
        }
    }
}
}