Hi, all. The Stoney Point headspace and OAL gauges are a goodness!
They have cut down my time and frustration a whole bunch. 'Course the old cut and try methods work too, just not as fast or accurately.
First, ANY of the reloading manuals (You do have a reloading manual, or three, right? You HAVE read it, haven't you? Not just the load section, either. ) will tell you that it is a rare rifle that works best with the bullet jammed into the lands. Pressures go crazy, and if you are working with near max loads, you could get hurt! Low pressure, cast bullet loads are the exception.
Most rifles shoot better with the bullet some distance from the lands. 010-.035 typically. Ross Seyfried opines that the correct bullet gap is of more importance to accuracy than all the messing about with primers, 1/10 grain differences in loads, or hiring Jennifer Lopez to breathe softly on your load will do--accuracy wise, you understand.
The Stoney Point tool uses a prepared case to measure the 0 clearance distance from bullet to lands. I am too cheap to buy all the equipment needed to use the modded case.
Smoking the bullet/using magic marker, measuring the OAL, measuring the rifling marks, and subtracting that from the OAL to get the TRUE OAL gives me a headache! But it works.
I prefer to use several unsized cases with lightly crunched mouths, and bullets seated gently, then chambered carefully in my rifle, and as carefully extracted. I take measurements of the several cases with the Stoney Point OAL gauge and caliper to determine an average OAL, which, if done right, will give you a working zero clearance. Set your seating die to whatever bullet to land gap you like, and it is an arbitrary choice for the first one. I make it a practice to never go below a .010 gap. Set your calipers at that number--IT is SMALL! .005 needs a light behind the caliper to see it. A human hair is maybe .003 in. We are talking tiny little differences, here.
The Stoney Point OAL gauge measures distance from the ogive or near it on the bullet, so the distance from that diameterto the rifling is a constant and repeatable number, or close enough for 98% of the handloader's needs. Measure it once, pick your gap, and no matter what bullet you use from then on, the distance from the lands will be the same, if nothing else changes. If that distance is consistent, and accurate, you will never have trouble with overlength loads causing high pressure, no matter which bullet you choose.
You don't have to have the latest high-zoot caliper, either. I used a cheap plastic one from Montgomery Wards for years, till I got one of Midway's metal ones on sale. Both of them agree amazingly well. Close enough for any handloading exercise.
Just establish what bullet to land gap works best for you an your rifle,and your ammunition, and have at it!
The simple way: Buy a box of your favorite factory ammo for your Remchester, be sure it fits, measure the OAL with the Stoney Point, set your seating die to that length. Then go shooting!
It actually takes more time to tell about it than to do it. Good luck, whichever method you choose.