This may sound stupid but i have two projects going and I was hopeing that some of the good pepole here would have some insight to what I am wanting to do ........

I have a 870 and a small ring mauser 308 and the bolts in both are chromed and I was wondering how I could get make them black so that they match the guns finish when I do them and I was wanting to do some kind of spray and bake  flat black tatical looking thing


any input would be helpful

Try aluminum black. Its kind of like gun blue but will turn steel black. You dont have to heat it or anything. I used it on a old yugo 8mm mauser i just bought and the bolt first turned a light black almost grayish color after a couple of my dips the bolt turned dark black. But thats just my country opinon  

Are you sure the rifle bolt is chromed?  Often they're just bright polished.

As for blackening chrome, there really isn't any way short of stripping the chrome and applying a different finish.

The reason gun parts are chromed is because it resists rust or darkening of the metal.  There is no chemical I know of that will blacken or even darken chrome that won't also damage the part.
Since chrome is so slick, the baked-on finishes don't sick to it very well at all.

In the case of the 870 bolt, instead of going to the expense of stripping a good bolt, some options are:
1. TRADE the chrome bolt for a black bolt.  
Many people have Express or Police guns with black bolts and would love to trade for a chrome bolt.  The chrome bolt resists wear and fouling much better and many people would like a chrome over black bolt.
TRADE and you're both happy.

2. Buy a new or used black bolt on Ebay or by advertising on the gun forums, then SELL the chrome bolt.  Chrome bolts typically bring much higher prices than black.

870 bolts are "drop-in" parts that don't need any head spacing or fitting.
Rifle bolt DO need fitting and head spacing, so in the case of your rifle, your only option is to have the chrome stripped.

Chrome is best stripped by having a plater DE-plate the part.  This is a reversal of the plating process in which instead of depositing chrome on the part, the process removes it.

There is no practical method of stripping chrome by hand.  Attempting to remove a plated finish by polishing is not effective, since plating will remain in the pores of the metal, and aren't apparent until you attempt to apply a chemical finish.  Then the part will have a "freckled" look where the chemical won't take.

In your case, I'd first test the rifle bolt with some cold blue to positively ID whether the bolt is actually plated or just polished.

In either case, there is no way to darken the bolts short of stripping the chrome.

Thanks for the info guys  I will try the cold blue test and go form there