Help with brass prep please

[Osideguy]

Now I know this is knit picking but here goes. I tumble my 9mm brass for a few hours in lyman corn cob and I add a bit of Nu-finish. After a few hours the brass looks great. Nice and shiny. However after I handle the brass it tarnishes pretty bad by the next day. The brass that I haven't handle still looks great. I thought it was from my hands but my factory ammo that I handle doesn't do this. Is this from a combination of me handling AND the nu-finish? Is there a product instead of nu-finish that would help? I understand it's probably from my touching them but like I said my factory ammo doesn't do this. Any help is appreciated.

[74c5]

5 bucks for a box of latex or nitrile gloves at OSH or ACE and you'll be fine. No idea what they put on factory loads but, they aren't purty forever.

[Timberwolf]

Brass tarnishes from the oil in your hands (remember smudged buckles and collar brass). Just use surgical gloves. I've often wondered if factory ammo doesn't have a thin coat of lacquer on them to keep them from tarnishing with time.

[thomashoward]

eat potato chips while brass prepping?

[23's Dad]

Is it too clean?

It seems to me that Nu Finish basically leaves the brass "stripped". I use a pinch of Mother's Mag Wheel polish in my walnut. Maybe not the right stuff, but it works for me. The MSDS doesn't list any ammonia...

[Dutch3]

I use a little "TR-3 Resin Glaze" in my walnut.

I think it is basically polishing compound + wax.

[Osideguy]

Thanks guys and no on the potato chips. :-) I'll get some gloves. Also I considered using Flitz polish but can't find it locally.