Assume your 336 is a .35 Rem?
If so, I doubt that you will be able to load to the crimp groove - throats are almost certainly too short. Marshall does have one bullet that will load to the crimp groove, I think it is designated "+P" as it was originally designed for loading in .38 special brass for .357 handguns. But the standard 185gr. WFNGC won't load to the crimp groove for the Marlin 336 in .35 Rem.
I have loaded some of the standard 185gr. WFNGC in my 336, with mixed results, BUT I had some accuracy problems that needed to be straightened out first (for both cast and jacketed).
What I would do first is try to discover the max OAL that will chamber in your gun (make up a few dummy rounds then find out where the rifling will just touch the bullet nose). Then, load to that length, and after seating bullets, give the case mouth a gentle bump with the crimp die, to prevent bullets from being forced into the case mouth. You would probably be well advised to get a Lee factory crimp die, which makes the issue of where the crimp groove is located, moot.
Once I straighted out my accuracy problems, I am getting less than 1 MOA with Fed. 200gr. jacketed, and just over 1 MOA with some bullets from an RCBS 200gr. GC mould, not sure which number exactly, but it's a flat nose design.
My load data was just taken from the Hodgdon manual for jacketed bullets of the same weight, and worked up using Varget.
By the way you can neck-size .35 Rem brass with a .357 carbide sizing die, which is easier when you just want to load a handful of rounds and will only be shooting them on the range. I also use a Lyman "M" expander, to help seat bullets straight.
Sorry to not provide more load data, but when I got the results I did with just one powder, didn't see the need to do much else. I have some 185gr.GC bullets also and intend to try some more loads with them, and will post results when I get more information.
There are other powders more commonly used in the .35 Rem like IMR 3031, 4895, H335, etc., but Varget was what I had on hand.