#include sdktools
public OnPluginStart()
{
    HookEvent("upgrade_pack_used", EventP, EventHookMode_Pre);
}

public Action EventP(Event event, const char[] name, bool dontBroadcast)
{
    int i = GetClientOfUserId(event.GetInt("userid"));
    int entity_id = GetEventInt(event, "upgradeid");
    float origin[3];
    GetClientAbsOrigin(i,origin);
    new pack = CreateEntityByName("weapon_ammo_spawn")
    DispatchSpawn(pack);
    DispatchKeyValueVector(pack, "origin", origin);
    AcceptEntityInput(entity_id, "kill")
}