what low risk mutual funds have historically best results, as a 6-12 month investment?

For a 6-12 month investment, I think a certificate of deposit is your best bet.

You don't want to look at mutual funds, not even traditionally low-risk funds. Stocks are too volatile. Sure, they may go up, but they may also go down, and over that short a term, normal price noise could put you on the wrong side of your purchase price when you need the money.

An ultra-short bond fund MIGHT work, but if rates go up, you may lose value.

Well see theres a promblem with your question... its a contradiction = X!

If it's a low risk mutual fund, well then you shouldn't expect 'best results'...

Can I suggest you looking at blue chip mutual funds? These have risk of course, but when the market does well, you can expect it to be in line with the market and even beat it

Two I like:

JIBCX & FCNTX

Frankly, 6-12 months is too "short term" for mutual funds. Stick with a CD or 12-month T-note.

fidelity

Fidelity Magellen