If you really fit a military stock, then by all means use its measurements when ordering another gun. Just check a few things, first. When you mount that gun to your shoulder, standing upright, are you looking through the middle of your glasses at the rear sight on the rifle, or out of a top corner, or edge? IF the latter, the stock does not fit you well: you have just learned to use it. The reason most people don't have custom fitted stocks on their rifles is that just learn to " Make do ". With a shotgun, fit is much more critical, and this is where we see shooters looking for a stockfitter.
Next, is your checkbone laying on top of the comb, or along side it? If the former, you are being hurt by the recoil. Some guys just learn to " take it " ( like a man!), but they are just fooling themselves if they think that recoil beating is NOT affecting their shooting scores.
Finally, after a shooting session where you fire 20 or more rounds of high power rifle cartridges, do you have a bruise on your arm, or shoulder or chest? If so, take a picture. if only the bottom of the buttstock is leaving a " U-shaped " mark on your pectorals, you can stand to have some wood removed from the Toe, or bottom part of the butt. This is PITCH. ( I call it Down pitch, because most shooters need to have a greater down pitch to allow their heads to look straight ahead, and still see both the rear and front sites, comfortably.
How to take the measurements of different stocks so you can compare those who feel better to you, to those that don't? Its rather straight forward, if not simple.
PITCH: is meaured by standing the rifle on its buttstock against a doorjam, or wall, so that the heel, or top of the stock at the butt is against the jam or wall. Somewhere around the rear sight, ( remove the scope and mount from such guns) the action or barrel will also touch the wall. The front sight- way out at the end of the barrel should stand out away from the wall or jam. Measure the distance from the Wall or doorjam, to the top of the fronts sight, and record that measurement. That is the amount of PITCH that rifle or shotgun has.
LENGTH OF PULL: This is the distance between the middle of the triger that fires the gun to the center of the buttplate. On most factory stocks, this will be in excess of 12 inches. Record that measurement as this is the gun's LOP.
DROP AT HEEL; AND DROP A COMB: The heel is the top of the butt. If you think if a gunstock standing against a wall, it sort of resembles the human foot and leg. The heel is against the wall, and the toe is away from it. The COMB is that portion of the top of the stock the starts behind the wrist of the stock. you measure the drop at comb at the forward most point of the comb.
To measure drop, use a straight edge( Yard stick, 1 x lumber, whatever you have that you can lay along the top of the barrel to extend back over the buttstock. Measure your DOC as the distance from this line represented by your straightedge to the top of the comb. Measure you DOH by measuring the distance from the straightedge to the top of the heel of the stock.
Those are the four measurements a stockmaker needs to make a stock that fits you. If he doesn't take your measurements himself, he is relying on your sole judgement as to what fits you. He will make the stock to the dimensions you give him. If you give him wrong measurments, its your fault that the stock does not fit. So do this right. Measure lots of stocks, shoot as many rifles and shotguns as you can, and ask experienced shooters, and particularly any that have custom stocks, or non factory stocks on their guns, to look at your stance and position to suggest any corrections that need to be made by you to shoot better. Many of them will have already gone through this process themselves and will be very sympathetic and helpful to you. There are no nicer groups of men than shooters.
One last item you need to know about, even if you may not be interested in it. That is " CAST ON " AND "CAST-OFF". Cast represent a bending or curve of the buttstock from the centerline of the forestock and barrel. Cast-on is where the stock is bent to the right, as you look down on the stock from above the gun, or towards the face of a LEFT-HANDED shooter. CAST OFF is where the stock is bent to the LEFT, away from the face of a right handed shooter. If you have a wide face or head, or have put on weight, CAST OFF can allow you to more naturally align your eye with the sights of the gun without crawling on top of the stock with your cheekbone to get there. Some stocks have rather high combs because the factory expects 99% of the shooters to put a scope on the rifle, and the extra height is needed to get the head high enough to look easily through the scope. The Marlin 22 rifle you speak about is that way. take its measurements just to know, and then try one with and without a scope sight. I think you will find that I am correct. The advent of scope sights has changed the stock dimensions of most modern made rifles. You need more drop at comb, and heel, and usually more down pitch on a ML rifle to have it mount properly to the pocket in your shoulder, next to your cheek to be fired. Down Pitch often can be used to rescue a stock with too high a comb so that a shooter can see his iron sights with that high comb. It all depends on how long a neck the shooter has, whether this can work or not.
As to Cast-Off, and Cast-On, the measurement is made at the butt, and is usually a fraction of an inch. I have 1/4" cast-On done to my Remington 870 LH pump shotgun because I have a full face, and that allows me to align the front sight quickly when I mount the gun to my shoulder. I stopped missing a lot of targets as soon as I had that work done. I have not had that kind of work done to any of my rifles, other than my Fowler, yet! I am wanting to get a replacement stock for my 12 ga. S x S CVA shotgun, and when I do, I will order it with Cast-On to fit me better.
Those are the needed measurements you want to give to a stock maker. And, you really need to know these measurements when you look at guns in the stores. Take a tape measure with you. The top of a glass covered case can provide the straight edge you need to measure DOH and DOC. just turn the gun upside down and lay it on the top of the table or counter, and measure from the glass up to the comb and heel. Every business has a doorway, and every door has a doorjam, so getting the pitch measurement on a gun is not difficult, either. Finally, the tape will easily give you the LOP.
