After a pleasent day at the range I stopped by my local gun store to buy a boresnake to make cleaning less of a hassel. They did not have any boresnakes in 9mm so I bought the .357 being only .001 of a inch difference. So I go home break down the Sub and begin cleaning the gun. I began to run the snake through the barrel and I pulled but it wouldnt budge. I tried my hardest to pull it through without breaking it but it wouldnt yeild so I went back to the gun store and I told the man who sold it to me my problem. I gave him the boresnake and he ran it through the 9mm sub 2000 they had in stock and it went through just fine. This kinda worried me but the employee let me switch it out for a .30 bore snake and it fit just right for my gun. Should I be worried that the bore of the barrel is smaller than normal? Would this cause any problems while firing it that may damage the rifle? Any help or advice would be great.