Cerakote Graphite Black H-146 is a great color but it's just a bit too dark.
Could H-146 be "lightened-up" a bit by adding some small amount of FDE to the mix??
The goal color is shown below (the mil-spec barrel)
Any information you have would be great

Tisas has a near exact match.

I've found Jet Black (air cure) to be a really good match to the chalky, super dark gray of type III hardcoat anodizing. Down side, is, it gets shiny over time with wear, not unlike anodizing, but at a more rapid rate. Other than that, Cerakote "blacks" are "too" black compared to the parking.

The problem I've found with Cerakote gray's is they tend to be on the blue-tone side. I coated a knife in Sig Dark Grey a few months ago (bake cure) and it's been holding up well keeping a nice matte sheen. It is a bit warmer tone, maybe on the green side which could be ideal for a parking match. I would darken it slightly with Armor Black, and see what you can drum up.

I feel like this is the third thread in a row where I've touted Norrell's Moly Resin as the solution, but it works really well for grays. I run a mix of about 65% Grayish-Black, and 35% SOCOM black for mimicking parking and it looks really good. It's close enough to the color temperature to not be seen as "blue" tone. Just make sure you mix the components well, preheat the part before spraying, and get a nice matte finish on it. It appears darker if it ends up shinier than matte due to unmixed paint, a cold part to be sprayed, or sprayed too thick in one pass. (Still looks good, just not like matte parking)

The other Cerakote option you could consider is the new Gen II HIR signature reduction coating line in "Graphite Black." I've been really impressed with the durability of this product since I've been experimenting with it. It looks like blue ink in the bottle, sprays like a brown black, then cures like a super dark gray. (Voodoo magic, I have no idea...)

We're launching an AKM manufacturing business in a couple months and will be using Gen II HIR Graphite Black to coat our barrel assemblies for those who want a traditional black/blued steel look without it sticking out under IR, or resorting to older, less-protective methods. (Nothing wrong with the classics, we're just building "modern" variants of the platform.)

I suggest this product because if you spray it wet at 18:1 ratio, it gives the appearance of something between blued steel and well oiled parking. I am currently testing different spray methods, atomizing pressures, and hardener ratios to get it super matte finish. Even when cured, it is not a true black, and in this instance that is perfect for us. As I play with it more, I'll post some photos. I think you may be able to achieve that parked look with this Cerakote product.

Good luck, and let us know if you come across an effective solution!

Last summer I milled down a hand guard for a custom length and wanted it refinished in cerakote to best match a standard black anodizing. I always use Mad Custom Coating for any cerakoting and asked them what they suggested. They said Armor Black with a matte finish is the closest they have that mimics the looks of factory black anodizing. I was very happy with the results.

My mistake, I completely misread your question on what you were looking for. Not awake yet.