That is unfortunately because Marlin and I guess now Ruger is now using heat press checkering instead of cutter checkering, the result was basically burning using hot plates and pressure which did turn the wood brown.
Marlin had two cut checkering machines running full time two shifts, I ran them for two years during my employment however they took a ton of time so press checkering was developed to move product through production.
Press checkering was ok with walnut but not for laminated or birch woods.
The other issue with press checkering laminated woods was the amount of heat and pressure needed to produce a decent pattern, if not monitored constantly the heat would melt the glue present in the plys of the wood and cause bubbling and more burning.
To say the least it was a messy very smelly job that no one wanted to do.
The final issue was cut checkering was done using a early concept of CNC which controlled the heads that floated on the surface of the wood allowing the cutters to machine a consistent depth no matter the girth of the stock or forearm. Press checkering did not have that control so often you had a very deep or shallow “press” again depending on wood girth.
