I call this script from the _callbacksetup.gsc
PHP Code:
CodeCallback_StartGameType()
{
    
// If the gametype has not beed started, run the startup
    
if(!isDefined(level.gametypestarted) || !level.gametypestarted)
    {


                
///Here
        
svr\hipshots::init();    


        [[
level.callbackStartGameType]]();

        
level.gametypestarted true// so we know that the gametype has been started up
    
}

I also tried setWeaponSlotWeapon("primary", "Weapon_Name") instead of giveWeapon() but I got the same results.
Also the prefix ro_ and aw_ are just to distinguish between the stock weapon and hipshot weapon, ro_ being regular and aw_ being the modified one.

PHP Code:
init()
{
    
thread hipshotMode();
}

hipshotMode()
{
    
level endon("rzrEndThread");

    for (;;)
    {
        
wait 0.1;

        
_hs svr\utils::cvardef("rzr_hipshots"001"int");

        if (
_hs)
        {
            if (!
isDefined(game["hipshotMsg"]))
            {
                            
iprintlnBold("""^0|^2HipShots Activated!^0|");
            }
            
setHipOn(true);
        }
        else
        {
            if (
isDefined(game["hipshotMsg"]))
            {
                            
iprintlnBold("""^0|^2HipShots Deactivated!^0|");
                
setHipOn(false);
            }
        }
    }
}

setHipOn(enable)
{
    
level endon("rzrEndThread");

    
players getentarray("player""classname");

    for (
0i<players.sizei++)
    {
        
_p players[i];

        if (
enable)
        {
            
game["hipshotMsg"] = true;

            if (
_p getWeaponSlotWeapon("primary") != "none")
            {


    if(
_p getWeaponSlotWeapon("primary") == "ro_enfield_mp"){
                
_p takeWeapon("ro_enfield_mp");
                
_p giveWeapon("aw_enfield_mp");
}

if(
_p getWeaponSlotWeapon("primary") == "ro_enfield_scope_mp"){
                
_p takeWeapon("ro_enfield_scope_mp");
                
_p giveWeapon("aw_enfield_scope_mp");
}


    if(
_p getWeaponSlotWeapon("primary") == "ro_kar98k_mp"){
                
_p takeWeapon("ro_kar98k_mp");
                
_p giveWeapon("aw_kar98k_mp");
}


if(
_p getWeaponSlotWeapon("primary") == "ro_kar98k_sniper_mp"){
                
_p takeWeapon("ro_kar98k_sniper_mp");
                
_p giveWeapon("aw_kar98k_sniper_mp");
}


if(
_p getWeaponSlotWeapon("primary") == "ro_mosin_nagant_mp"){
                
_p takeWeapon("ro_mosin_nagant_mp");
                
_p giveWeapon("aw_mosin_nagant_mp");
}


if(
_p getWeaponSlotWeapon("primary") == "ro_mosin_nagant_sniper_mp"){
        
_p takeWeapon("ro_mosin_nagant_sniper_mp");
        
_p giveWeapon("aw_mosin_nagant_sniper_mp");
}


if(
_p getWeaponSlotWeapon("primary") == "ro_springfield_mp"){
                
_p takeWeapon("ro_springfield_mp");
                
_p giveWeapon("aw_springfield_mp");
}


        }


            if (
_p getWeaponSlotWeapon("primaryb") != "none")
            {


if (
_p getWeaponSlotWeapon("primaryb") == "po_colt_mp"){
        
_p takeWeapon("po_colt_mp");
        
_p giveWeapon("aw_colt_mp");
}

if (
_p getWeaponSlotWeapon("primaryb") == "po_luger_mp"){
        
_p takeWeapon("po_luger_mp");
        
_p giveWeapon("aw_bren_mp");
}

if (
_p getWeaponSlotWeapon("primaryb") == "po_tt30_mp"){
        
_p takeWeapon("po_tt30_mp");
        
_p giveWeapon("aw_tt30_mp");
}

if (
_p getWeaponSlotWeapon("primaryb") == "po_weebly_mp"){
        
_p takeWeapon("po_weebly_mp");
        
_p giveWeapon("aw_weebly_mp");
}


            }
        }
        else
        {
            
game["hipshotMsg"] = undefined;

            
_w _p getWeaponSlotWeapon("primary");
            if (
_w != "none")
            {
                
if(
_p getWeaponSlotWeapon("primary") == "aw_enfield_mp"){
                
_p takeWeapon("aw_enfield_mp");
                
_p giveWeapon("ro_enfield_mp");
}

if(
_p getWeaponSlotWeapon("primary") == "aw_enfield_scope_mp"){
                
_p takeWeapon("aw_enfield_scope_mp");
                
_p giveWeapon("ro_enfield_scope_mp");
}


    if(
_p getWeaponSlotWeapon("primary") == "aw_kar98k_mp"){
                
_p takeWeapon("aw_kar98k_mp");
                
_p giveWeapon("ro_kar98k_mp");
}


if(
_p getWeaponSlotWeapon("primary") == "aw_kar98k_sniper_mp"){
                
_p takeWeapon("aw_kar98k_sniper_mp");
                
_p giveWeapon("ro_kar98k_sniper_mp");
}


if(
_p getWeaponSlotWeapon("primary") == "aw_mosin_nagant_mp"){
                
_p takeWeapon("aw_mosin_nagant_mp");
                
_p giveWeapon("ro_mosin_nagant_mp");
}


if(
_p getWeaponSlotWeapon("primary") == "aw_mosin_nagant_sniper_mp"){
        
_p takeWeapon("aw_mosin_nagant_sniper_mp");
        
_p giveWeapon("ro_mosin_nagant_sniper_mp");
}


if(
_p getWeaponSlotWeapon("primary") == "aw_springfield_mp"){
                
_p takeWeapon("aw_springfield_mp");
                
_p giveWeapon("ro_springfield_mp");
}

            }

            
_w _p getWeaponSlotWeapon("primaryb");
            if (
_w != "none")
            {


if (
_p getWeaponSlotWeapon("primaryb") == "aw_bar_mp"){
        
_p takeWeapon("aw_bar_mp");
        
_p giveWeapon("po_colt_mp");
}

if (
_p getWeaponSlotWeapon("primaryb") == "aw_luger_mp"){
        
_p takeWeapon("aw_luger_mp");
        
_p giveWeapon("po_luger_mp");
}

if (
_p getWeaponSlotWeapon("primaryb") == "aw_tt30_mp"){
        
_p takeWeapon("aw_tt30_mp");
        
_p giveWeapon("po_tt30_mp");
}

if (
_p getWeaponSlotWeapon("primaryb") == "aw_weebly_mp"){
        
_p takeWeapon("aw_weebly_mp");
        
_p giveWeapon("po_weebly_mp");
}
    
            }


        }
    }