I've always chambered my own guns like this:



Such that the shoulder of the case was roughly even with the end of the largest diameter of the barrel.

(the photo is not good as it shows a .375 H&H case against a 6mm Rem barrel but you get the drift)

In this manner a .308 Win could weigh less than a .300 Weatherby.

It has worked well for me and this is what I was told to do back in the '70s when I started this (insane) hobby.

My question:

1. Is there an official depth of chamber that is considered correct for the barrel shank?

2. Can the barrel be further reduced in weight here by shorting it and chambering much deeper?

3. How do you decide where to trim this end of the barrel?

not a smith, but havve discussed these issues with my gunsmith enough to know that the general rule is as you do...the shoulder of the case no deeper than the junction of shank and taper at the same time you see feather wgt barrels with just a tny bit of a shoulder against the action and the taper/reduction of bbl.diameter abruptly taking off right from there. so, it is most likely a judgement call by the 'smith. something with a large case and lots of snort, you might want to have plenty of barrel around, and then a little extra weight on such gun means little....smaller cartridge, less horsepower, sliver of a stock, skinny barrel, run the skinny right up to the action with just a little shoulder/chamber shank for looks and weight.

Many factory offerings have no shank at all. They start a sporter style taper right where the action face meets the barrel shoulder. This is done with high pressure offerings as well as the milder stuff. If you were building an ultralight rig, a long shank wouldn't make much sense, but on a rifle where overall weight comes second to personal taste, then whatever floats your boat. Some of the nicest looking octagons posted on this site have the octagon starting a half inch from the receiver.

build em how you like em .. I've see german barrels with .2" or so "shank" with immediate step ..

featherweight barrels tend to be shorter .. and big boomers tend to be longer, in the largest, or "a" section on most barrel drawings.

but, remember, on the shoulder ... pressure builds AFTER the bullet leaves the chamber, for about 3-4" or so, in a bolt gun, according to all ballastic models .. that's bullet travel, NOT base to bullet (yes, i have asked the creator of quickload, as that was important to me)

so, the answer to your question, for the first 7" of a 375, it loads to max pressure, then falls off .. 7" from bolt face ... what's the diameter there?

I'm quite fond of the Douglas featherweight barrels (similar to if not the same as) the M-70 featherweight barrel.

In discussions with Douglas, they are quite insistent that those barrels are for .30-06 size cases only and not to be used for the magnum cases. Further they only make that barrel in .308 caliber max

Specifically.....if chambering a .375 H&H in a 1.200 shanked Doughlas $4 contour barrel, how deep would you run the reamer and still be safe?

People get away all the times with choices I wouldn't even consider. Heck, out here on this two-lane country road next to a river, with many sharp curves, some of them 180-degrees, I meet city folk all the time coming around the curves on my side of the road. So far bright lights and a loud horn have saved my bacon.

But my late old friend Paul Marquart, who was a barrel-maker and "gunschmidt" of some note, only had part of his left hand for the last approximately 15 years of his life. Lost the rest of it test-firing a rifle, which in turn led to a lawsuit being filed by Paul against his business partner up 'til then.

I don't know the details or the outcome of the suit, and don't want to get into either here.

But, ever since I've done what Paul advised me to do for high pressure rounds...make sure the front edge of the shoulder of the chamber is at least 1/2" behind the begining of the taper from the "barrel support" section of the barrel.

And in no instance have less than 15/64" thickness of steel all the way around the whole length of the chamber.

Probably not metallurgical engineer derived, but has worked out well for me.

Consider the breech diameters of drillings and double rifles, and Marlin Lever actions and it will scare you how thin they are. And all of them are not built for low pressure rounds.