Has anyone engraved a Lower/Upper Receiver?

[Fillar]

I have too many black rifles of multiple calibers. While I know which round is for which, I’m afraid if I go visit God or I’m traveling and a family member needs to grab one quickly, a wrong round may go into the wrong receiver.

1. How do you clearly decipher between your black guns? I tend to use the same Hand Guards for caliber type, and while I have it memorized my wife and teenage won’t keep them straight; my seven year-old probably can. 
   
2. I am thinking about having 6.5 Grendel engraved on two lower receivers, or do you suggest I have the uppers engraved in case I swap lowers?
   
3. Lastly, does engraving take a finish off the receiver that can then rust?
   

I appreciate any ideas.

[LRRPF52]

Since you live in a very high humidity, high salt environment, corrosion of aluminum can be an issue, but not so huge of one with engraved lettering.

The other alternative that won't compromise your anodized surface is to have them laser-engraved.

[Whelenon]

I would laser engrave the uppers to Cal specific, assuming all your uppers are complete units. I've talked to a local Trophy Shop who does laser engraving, he could engrave an upper on the flat just below the picatinny rail without a problem. Just like AA does with their receivers. The upper is alum so it's not going to rust. There are also ways to paint the lettering if you don't want to leave it silver.

[Dogue]

Lot's of people recommend Ken Smith in Largo http://designcreations2011.com/kensmithengraving.com/
For laser there's Accubeam in Sarasota http://www.accubeam.com/

[Fillar]

Laser engraving it is. Welenon, I like your approach on the upper. Thanks also for the local FL recommendations, Dogue.

[KentuckyBuddha]

I color and texture code mine to eliminate confusion. I expect in a situation in which I am stressed this would be better than reading the engraved markings, and I have made sure the folks that might come in if I get hit by a truck know the color codes. : )


But hey...if you want them all black an you like them that way maybe just an easy indicator or some kind. Like have the .223 left standard and have grendel with a free-float handguard or something might be a reasonable option, yhea?

[Whelenon]

The KBuddha is a wise man, there's always more than one way to get 'er done.