Standard Products Refurb

[Singer B]

It's not Oxpho liquid or Cream, Also not a type of cold blue. These don't build up the Mil Depth your seeing.

I believe you have what we call a 'Painter in a Can' product that has been used.
These Park 'Paints' come in Aerosol and liquid. Single stage and 2 part Epoxies. Liquids most often applied by Air brush, gravity fed cup and HVLP Sprayers. Some require oven time others just air dry.
These would be the only types that could cause this much depth, by applying multiple coats.
100's of them out there made for guns and Auto's. Made to match different Gun finishes and Auto parts. Some marketed as quick Zinc Phosphate, others to match raw Cast Iron which can look very much like Park sold by NAPA called Last Blast" and "Cast Blast".
DuraCoat, Brownells, NAPA, Eastwood.... etc

Spray Park Examples.....
DuraCoat's DuraPark: DuraPark Spray-On Parkerizing Replicator
Eastwood's Zinc Phosphate: https://www.eastwood.com/ew-zinc-pho...sol-12-oz.html

Here this link will save me some time. When opened go way down to 'Customers who viewed this item also viewed' to view many other makers:
Amazon.com : DuraPark - Spray-On Parkerizing Replicator : Sports Outdoors

When Looking at your Cast Recoil plate... Which are usually pretty smooth, shows yours with heavy Orange Peel. Often caused by product not being reduced enough. Recoating before previous coat was dry enough. Part is too hot or Air supply (Compressor) pushing hot air... causing product to set before it can self level out with slower drying. These are the most common reasons, Plus should add nozzle jet being too large and or wrong air pressure.
Of course this isn't important now that it's on.

Questions now are what all have been sprayed and how to remove it....... Without having to Re-Park the under laying Original Finish.

You could use Muriatic Acid, they now have a 'Green Version' that's less aggressive.
I use it full strength, but you can start with a mix of 3 parts Muriatic Acid to 1 part water to to reduce it and give you more working time. If not strong enough just slowly add more Muriatic Acid to the mix. ALWAYS ADD ACID TO WATER, NOT WATER TO ACID.

Brush some on a section of barrel and watch it work, brush again only to keep it wet.
Keep track of how long it's on when you can see it has pulled the new top coat away.
Rinse it, dry it, Then use this same amount of time when you drop the barreled receiver in.

Here you could try just slathering multiple brush coats on it, while on a piece of carboard or plywood.
I normally Dunk the barreled receiver with the Mur - Acid deep enough to cover it over in a plastic PVC pipe (Ends capped and top cut away wide enough to fit a barreled receiver).
Pull and rinse with soapy water, use a mix of ½ cup of baking soda and a quart of water in a sealed spray bottle to neutralize it and finish hose rinsing it off. Dry and oil.

I've stripped the black park that was applied overseas and revealed the Original Park.
Trick is just dunk for a short time, pull and rinse... Checking results.
If it stays in too long IT WILL REMOVE the Original Park.
I'd try 1 minute and pull. You'll be able to watch it work and pull it when 90%+ finished stripping new finish. You can always re-dunk for desired results.

But with you never doing it before you might consider trying a dunk or brushing of Lacquer Thinner first.
Which will not pull any Original Park off.
Spot Testing a Liquid Paint and Varnish stripper, might be another option.
You can test methods on the Recoil Plate.

I can say from multiple personal experiences that Muriatic Acid has worked very well for me. I just watch it and pull after I see the new added finish is gone.

Worth a try, because many that Re-Park will strip with it, then only have to lightly bead/media blast so the metal takes the New Park evenly.

Advise safety glasses, gloves, bailing wire attached to rear and Frt sight, And a Good Mask.
Take care not to burn your lungs....... Don't Ask

It sounds/reads like a bigger job than it will be. Mur Acid can be re-used for any other parts.

PM me with any concerns or need additional info.

HTH,

Thank you sir!! Looks like I am going to learn something over the next few days. And if I screw it up, I can always have a professional re-do it for me. Your instructions are very clear so I have a good feeling about this.