Being new to Maynards, where all late production barrels drilled and tapped for a forearm ??  I know the barrels with 9 inch flats where more likely to have a forearm vs. the 3 inch flat barrels.

The forend or tip stock as Mass Arms called it was only standard on the Model 16. It was an option on the other models including the shotguns. I don't think any of the #14 or Creedmoor models ever had forends. I don't think barrels were drilled and tapped unless it had a forend at one time. There is no standard dimension for the location of the screw. They all seem to have been hand fitted. Forends from one barrel will seldom fit another. If it does it is pure luck.

I think they all look better with a forend. The ones with the 9" octagon look especially odd without the forend.

Ya, as far as the forearm mounting holes, it was a 50/50 proposition.

Here is what I have, as measured from the inside of the barrel pivot hook surface to the center of the screw hole:

25-20 SS heavy barrel with 9 inch flats  3.302 inches
35-40 Maynard with 9 inch flats  3.145 inches
40-70 Maynard heavy round barrel  3.032 inches

One could assume that these might be factory, as they are all different, vs. someone drilling them themselves as most likely they would all be the same.

Assumptions can get you into so much trouble !!!

Anyway, as they do have them, I will probably try and locate some forearm wood to put on them.  While I'm at it, probably will replace the butstock as it has a crack and the wood is so dry.