I'm learning about Design Patterns using Unity and I'm not sure about how to solve the following problem with the Factory Method Pattern:

I want to read a XML file and using the Factory Method Pattern to create a Component (a Weapon) to add it to a GameObject which will be cointained on a Pool Manager, but Weapon "Is A" MonoBehaviour and for that reason It can't be instantiated using a "machineGun = new MachineGun();"

public abstract class WeaponFactoryMethod
{
    protected string fileName = "weapons.xml";
    public abstract Weapon CreateWeapon();
}

public class MachineGunFactoryMethod : WeaponFactoryMethod
{
    public override Weapon CreateWeapon()
    {
        string filePath = Path.Combine(Application.streamingAssetsPath, fileName);
        Weapon machineGun = null;
        XmlReader xmlReader = new XmlTextReader(filePath);
        if (xmlReader.ReadToDescendant("Weapons"))
        {
            if (xmlReader.ReadToDescendant("Weapon"))
            {
                do
                {
                    // I CAN'T DO THIS:
                    machineGun = new MachineGun();
                    machineGun.ReadXml(xmlReader);
                } while (xmlReader.ReadToNextSibling("Weapon"));
            }
            else
            {
                Debug.LogError("There aren't definition for Weapon");
            }
        }
        else
        {
            Debug.LogError("There aren't definition for any Weapon");
        }

        return machineGun;
    }
}

public abstract class Weapon : MonoBehaviour, IXmlSerializable
{
    public float AttackRange { get; set; }
    //Every weapons Shoots in a different way
    public abstract void Shoot();

    //Serialization
    public XmlSchema GetSchema()
    {
        return null;
    }

    public void ReadXml(XmlReader reader)
    {
        XmlReader childReader = reader.ReadSubtree();
        while (childReader.Read())
        {
            switch (childReader.Name)
            {
                case "AttackRange":
                    childReader.Read();
                    AttackRange = childReader.ReadContentAsInt();
                    break;
            }
        }
    }

    public void WriteXml(XmlWriter writer)
    {

    }
}

public class MachineGun : Weapon
{
    public override void Shot()
    {
        //Raycasting..
    }
}

At the end I want something like

GameObject (player)
 - Component (A Weapon script with the data from the xml)

Should I just create a GameObject (player) and do an "AddComponent < MachineGun >" and later copy the info from the xml file instead using the Factory Method Pattern??

Is there a better way??

Any suggestions, corrections or advice will be very grateful.

I'm sorry by my English.