Savage MK II TRR-SR feeding issues

I purchased this from a trusted gun shop. Took this in trade 200rds fired(gunsmith personally knew the customer).
Have used Gemtech, Fed blue box bulk, American Eagle, Rem Golden bullet and Win. 40gr truncated cone HP.
I have 5 & 10 rd mags.
When the mags get 3-4rds from empty as the bolt catches the base of the bullet it pushes the nose of the bullet down and hits the bottom of the chamber stopping the chambering process.
Only does this for the 3rd and 4th rd from empty,
My gunsmith says he has a rubber tool with embedded diamonds and wants to slightly round the bottom of the chamber opening to help feeding.
Any other options available? I'm stumped about what to do.

I also have feeding issues with my 10 round mag that came with my mark II. I noticed if your slow with the cycling of the bolt it seems to help. I took mine out Friday and did this and had little problem. My 5 round mag I have no problem. It cycles flawlessly. I used RWS and Remington ammo.

I loaded my mags and cycled slowly while watching.
When a fail to feed happened the back of the brass failed to pop up into the bolt when pushed forward till it contacted the face of the barrel, not lined up to the proper alignment to the chamber.
It always happens with 3 and 4 rds left in the mag.
Do I need to cut a small amount of the forward edge of the top curved part of the feed lips? Or opening or spreading the feed lips so the round pops up earler?

I cleaned the bolt and looked for burrs or anything that would interrupt the feeding of a round, didn't find anything I could see wrong with face of the bolt.
But I did find what I thought was not normal wear on the bottom of the bolt. Here are the picturers, Is this normal wear for no more than 400 rds fired?



http://s1262.photobucket.com/user/fa...?sort=3&page=1

Got the feeding issue fixed. I did as the link suggested and all is good now.
http://www.rimfirecentral.com/forums...d.php?t=281308