Scooter,
I bought a new 22 lr Sportster a while back and it wasn't shooting a tight of groups as I thought it should. I usually try about 10 different brands/style of ammunition in my 22 lr's to see which it favors. I had read about polishing the bore somewhere and decided to polish this little 22. I used a wooden dowel rod, small patches and Flitz to polish the bore. Took quite a while, but the results at the range showed that is was a worthwhile effort. In the future I plan to polish the bores on all 22 lrs that I get.
Don't know if the same would be true for center fires, but it worked for me on the 22 lr.
Everyone seems to have different ideas about whether or not to polish the bore of a new rifle, guess you'll just have to make your own decision.
Roudy