Our method of staining is as follows
1 coat of Mohawk brand wood dye to set a base layer color. Lightly sand to add color variation/distressed look
1 coat of stain, let dry over night.
2 coats of clear shellac. Polish by hand with a rag. You can also leave out the wood dye but you may need more layers of stain to get an even color. Stain won't soak into highly sanded areas as well as rougher areas so it will appear lighter. Dye penetrates pretty evenly no matter how much or little the area is sanded, that's why I use it so set a uniform base color before staining.
Otherwise here's an informative article on Baltic Birch that should get you started. https://www.woodworkerssource.com/blog/woodworking-101/tips-tricks/your-ultimate-guide-to-baltic-birch-plywood-why-its-better-when-to-use-it/
I’m going to order dong for zpap m70. The upper is maple. What finish should I choose to match rather than having to buy upper too?
Light finish will be closest to maple. It's a light brown/orange color.
I bought a standard dong from you dark option and it’s perfect. What color die and stain and dye could I use to get stock close to that color? Would appreciate any help
"Dark" color option is created with 1 medium coat of Mohawk ULTRA PENETRATING NGR DYE STAIN EXTRA DARK WALNUT 1 thick coat of Minwax English Chestnut 233, wipe off with paper towel let dry over night 1 spray on coat of clear Zinsser Shellac
will this fit my Pioneer Arms Sporter Underfold Stock AK-47?
Yes, that's standard fitment.