C-Sharp: Objekt ohne Ruckeln und Flackern in GUI bewegen

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace WindowsFormsApplication1
{
    public partial class Form1 : Form
    {
        int pos = 0;
        Timer t = new Timer();

        public Form1()
        {
            SetStyle(ControlStyles.OptimizedDoubleBuffer, true);
            SetStyle(ControlStyles.AllPaintingInWmPaint, true);
            t.Interval = 20;
            t.Tick += timer1_Tick;
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            t.Start();
        }

        private void Form1_Paint(object sender, PaintEventArgs e)
        {
            Graphics g = e.Graphics;
            g.DrawRectangle(new Pen(Color.Red,2),10,pos,50,50);
        }

        private void timer1_Tick(object sender, EventArgs e)
        {
            this.Refresh();
            pos += 1;
            if (pos >= 50)
            {
                t.Stop();
            }
        }
    }
}