Only time I have ever seen a difference with cleaning a barrel after every shot for the first 25 and then every 2nd until 50 was with a BAR in 7 mag. The Browning Rep told me to do that and it really helped with group size. It hasn't made 2cents difference on anything else I have. When I had a rifle rebarrelled with a custom barrel I only cleaned it everytime I shot it and that was max of 20 rounds.