Taken from my new upcoming mod (inTime), hope you can find it usefull

When you take your last ks, the count will restart like mw3.

 

To use it edit _killstreaks.gsc adding this and call showKillstreaksList( 145 ) when player connect and monitorCurStreak( 145 ) when player spawn

showKillstreaksList( inizio )
{    
   killstreak0 = self getPlayerData( "killstreaks", 0 );
   killstreak1 = self getPlayerData( "killstreaks", 1 );
   killstreak2 = self getPlayerData( "killstreaks", 2 );
   streakShader = "MADE BY Puffiamo | Steam: Puffiamo94";
   self.streakCost0 = "MADE BY Puffiamo | Steam: Puffiamo94";
   self.streakCost1 = "MADE BY Puffiamo | Steam: Puffiamo94";
   self.streakCost2 = "MADE BY Puffiamo | Steam: Puffiamo94";

   for(index=0;index<4;index++)
   {
       switch( index )
       {
           case 0:
                   streakShader = maps\mp\killstreaks\_killstreaks::getKillstreakIcon( killstreak0 );
                   self.streakCost0 = maps\mp\killstreaks\_killstreaks::getStreakCost( killstreak0 );
                   if( self _hasperk( "" ) )
                       self.streakCost0--;
                   break;
           case 1:
                   streakShader = maps\mp\killstreaks\_killstreaks::getKillstreakIcon( killstreak1 );
                   self.streakCost1 = maps\mp\killstreaks\_killstreaks::getStreakCost( killstreak1 );
                   if( self _hasperk( "" ) )
                       self.streakCost0--;
                   break;
           case 2:
                   streakShader = maps\mp\killstreaks\_killstreaks::getKillstreakIcon( killstreak2 );
                   self.streakCost2 = maps\mp\killstreaks\_killstreaks::getStreakCost( killstreak2 );
                   if( self _hasperk( "" ) )
                       self.streakCost0--;
                   break;
       }
       self.killstreaks_list[index] = self createFontString( "objective", 2 );
       self.killstreaks_list[index].foreground = false;
       self.killstreaks_list[index].hideWhenInMenu = true;
       self.killstreaks_list[index].fontScale = 0.60;
       self.killstreaks_list[index].font = "hudbig";
       self.killstreaks_list[index].alpha = 1;
       self.killstreaks_list[index].glow = 1;
       self.killstreaks_list[index].glowColor = ( 0, 0, 1 );
       self.killstreaks_list[index].glowAlpha = 1;
       self.killstreaks_list[index].color = ( 1.0, 1.0, 1.0 );
       switch( index )
       {
           case 2:
                   self.killstreaks_list[index] setPoint( "RIGHT", "RIGHT", 0, inizio-(25*2) );
                   self.killstreaks_list[index] setShader( streakShader, 20, 20 );
                   break;
           case 1:
                   self.killstreaks_list[index] setPoint( "RIGHT", "RIGHT", 0, inizio-25 );
                   self.killstreaks_list[index] setShader( streakShader, 20, 20 );
                   break;
           case 0:
                   self.killstreaks_list[index] setPoint( "RIGHT", "RIGHT", 0, inizio );
                   self.killstreaks_list[index] setShader( streakShader, 20, 20 );
                   break;
       }
   }
}

monitorCurStreak( inizio )
{
   self endon( "death" );
   self endon( "disconnect" );

   giroCompletato = undefined;
   killstreak0 = self getPlayerData( "killstreaks", 0 );
   killstreak1 = self getPlayerData( "killstreaks", 1 );
   killstreak2 = self getPlayerData( "killstreaks", 2 );
   streakCost0 = self.streakCost0;
   streakCost1 = self.streakCost1;
   streakCost2 = self.streakCost2;
   if( self _hasperk( "specialty_hardline" ) )
   {
       streakCost0--;
       streakCost1--;
       streakCost2--;
   }
   self resetList( inizio, streakCost0 );
   for(;
   {
       self waittill( "killed_enemy" );
       if( self.pers["cur_kill_streak"] < streakCost0 )
       {
           self.killstreaks_list[3] setPoint( "RIGHT", "RIGHT", -25, inizio );
           self.killstreaks_list[3] setText( streakCost0-self.pers["cur_kill_streak"] );
       }
       else if( self.pers["cur_kill_streak"] < streakCost1 )
       {
           self.killstreaks_list[3] setPoint( "RIGHT", "RIGHT", -25, inizio-25 );
           self.killstreaks_list[3] setText( streakCost1-self.pers["cur_kill_streak"] );
       }
       else if( self.pers["cur_kill_streak"] < streakCost2 )
       {
           self.killstreaks_list[3] setPoint( "RIGHT", "RIGHT", -25, inizio-(25*2) );
           self.killstreaks_list[3] setText( streakCost2-self.pers["cur_kill_streak"] );
       }
       else if( ( self.pers["cur_kill_streak"] == streakCost2 ) )
       {
           if( !isDefined( giroCompletato ) )
               self resetList( inizio, streakCost0 );
           giroCompletato = 1;
       }
       if( isDefined( giroCompletato ) )
       {
           if( self.pers["cur_kill_streak"] == streakCost0 )
           {
               self maps\mp\killstreaks\_killstreaks::giveKillstreak( killstreak0 );
               self maps\mp\gametypes\_hud_message::killstreakSplashNotify( killstreak0, undefined, "pickup" );
           }
           else if( self.pers["cur_kill_streak"] == streakCost1 )
           {
               self maps\mp\killstreaks\_killstreaks::giveKillstreak( killstreak1 );
               self maps\mp\gametypes\_hud_message::killstreakSplashNotify( killstreak1, undefined, "pickup" );
           }
           else if( self.pers["cur_kill_streak"] == streakCost2 )
           {
               self maps\mp\killstreaks\_killstreaks::giveKillstreak( killstreak2 );
               self maps\mp\gametypes\_hud_message::killstreakSplashNotify( killstreak2, undefined, "pickup" );
               self resetList( inizio, streakCost0 );
           }
       }
   }
}

resetList( inizio, streakCost0 )
{
   self.pers["cur_kill_streak"] = 0;
   self.killstreaks_list[3] setPoint( "RIGHT", "RIGHT", -25, inizio );
   self.killstreaks_list[3] setText( streakCost0-self.pers["cur_kill_streak"] );
}

Thanks, this looks really handy. :3