How to clean up these bayonets?

[gtodave]

Recently inherited these bayonets. They've clearly been touched up with something. You can see "overspray" on the handles. I'm planning to sand blast them down and cold blue them, but I wanted to check with the braintrust before I went and potentially ruined them.
Thoughts on what this is? Seems stronger than paint. Am I making a mistake removing it?

 

[bbrown]

Japanese Type 30 bayonets. Some blades were polished, some were blued. If you must sand blast them then please carefully remove the wood grips or thoroughly mask them off first.

Markings on Japanese Arisaka Rifles and Bayonets of World War II

 

[Doco Overboard]

Looks like galvanized roof paint.
I would bead blast them and not sand blast them and chemically black oxide them with a homemade concoction or an express.hot water blueing agent then rub linseed oil into them.
Dismantle the grips before the blast cabinet of course and a coat of fiebings saddle or dark brown on the scales before introducing the oil.

 

[TI-tick]

IDK, just tossing it out there.
Pull the wood off and put the metal in an ultrasonic.

 

[gtodave]

Japanese Type 30 bayonets. Some blades were polished, some were blued. If you must sand blast them then please carefully remove the wood grips or thoroughly mask them off first.

Markings on Japanese Arisaka Rifles and Bayonets of World War II

Interesting. I inherited them from my grandpa who fought the Japanese in WWII. I wonder if he brought them back.