However, when we buy a barrel, the kind of barrel is of great import. Real world problems make this a bit more complicated. An example of this would be button rifled barrels. They cannot be button rifled with thin walls, as is found in many finished rifle barrels (I'll limit this to the M14, M1 Garand & M16/AR15 barrels). They must be buttoned with thick walls, otherwise the process will bulge/distort the barrel blank wall. So, in the best case, you get a real fine internal bore with, say, 1.1" of steel surrounding it. What to do? Well, one must put it on a lathe & turn it into a Garand barrel, M14/M1A barrel, etc. Unfortunately, the area that most of the metal has to be hogged off is the most important part; the muzzle end! Changes in the bore dimensions will likely occur. So, that almost perfect buttoned blank you bought may become quite imperfect when it becomes the barrel you need.
Another example would be hammer forged barrels. The start up cost to hammer forge a fine barrel is quite high, compared to the other 2 methods discussed. However, once done, fine finished barrels can be replicated at a relatively low cost. That's its benefit. If the barrel is a finished, fully contoured barrel, this is a very fine & cost effective way to make a good barrel. In the best case. However, if you get such a blank & turn it into your skinny ended barrel, oh boy, look out! The internal dimensions will likely change a great deal more than a comparable buttoned barrel blank.
Lastly, is the cut rifled barrel. There are 2 distinct types: Broached cut & single point cut methods. Both can be used to cut the rifling in a finished, skinny barrel. All M14 G.I. contract NM M14 barrels were produced by the broach cut method. Many consider these barrels to be the finest ever made, in their given contour (most were standard weight, the rest were medium weight, though there is one rare additional heavy weight barrel contract not germaine to this discussion). Broach cut rifling is a fine way to make a barrel, & a reasonably cost efficient method. In the DCM Service Rifle category, many believe that the broach cut barrels won more points, & champions, than any other method. But then, they have been around longer than any other.
Now, to the other cut rifled method: Single point cut rifled barrels. A broacher is a very efficient way to cut the barrel bore, as it does so, normally, in one pass. Cuts all 4, or 5, or 6 grooves with just one single pass. Single point cut barrel makers (I am referring now only to Obermeyer & Krieger for this discussion) make many, many passes to cut just one groove. VERY stress free. AND, as mentioned, this method can cut the bore on a finished & fully machined barrel external! So, you get the barrel you paid for. Unfortunately, the only barrel maker that takes full advantage of this process is Krieger. He fully contours the external before he rifles it. The best of all possible worlds.
What's odd about all this is, the least stressful method, the method that can cut your internal on a skinny walled finished barrel, the single point cut method, is also the best barrel blank to get if you have to machine it into a skinny finished barrel. Why? because it's the least stressful process, & thus should maintain the fine internal dimensions better than other methods, when turned into a skinny service rifle barrel. The down side? They are quite expensive. Fulton Armory offers Krieger single point cut rifled barrels in its world class Peerless M14/M1A, M1 Garand & M16/AR15 Match Rifle upgrades. We offer a money back guarentee, so they have to be the best!
For bench-rest rifles, where the finished barrel diameters are often quite close to the original barrel blank, the above discussion becomes far less useful. I believe that's the area Mr. McMillan was commenting on. McMillan products are the finest available. Fulton Armory offers their world class stocks as an upgraded option in building its Peerless M14/M1A rifles.
I hope this long winded explanation is of some value. Thanks for your attention.
Clint McKee