I assume you'll be doing a take-down, otherwise you'll have to remove the barreled action from the stock each time you change barrels. My advice is don't do a swap barrel, non-takedown. It just isn't worth the trouble.
You almost certainly will be using a mauser if you build this rifle. You need an action with an abuttment ring so that you can get consitant headspacing. You'll probably want an interrupted thread mechanism.
After taking the rifle apart a few hundred times, there will be a little set back. So you will want to make an allowance to tighten up the barrel at a later date (most likely your kids or grandkids will do this after you're long gone). This is no big deal unless you want sights on your barrel. Your sights will have to be able to be rotated back to the 12 o'clock position, otherwise you'll eventually be holding your rifle sideways like some East LA gangsta.
A single forearm is a hassle also because you will have to change it over each time you switch barrels. Also your light caliber barrel would have to be the same contour as your heavy caliber barrel. For example you'll end up with a too heavy 300 or 338 win mag barrel and a too light 416 Taylor barrel. Not terrible, but in a custom gun, right is nice.
So, in my opinion, this is all a little more complicated than it might seem at first blush. Now we get around to answering your question; figure an extra $1200 - $1500 for the take-down option (depending on if/how you want to do the iron sights) and an extra $1200 - $1700 for the switch barrel and forearm. Remember, there's some extra hardware in the forearm that has to be duplicated and inletted. All this is for a full custom, wood-stocked job by someone who has done it before.
I have a take-down mannlicher-stocked 6.5X55 that I love. I just try not to think about what I've got in it.
Dakota does a take-down with an extra barrel as an option. Look at www.dakotaarms.com
[This message has been edited by ForrestB (edited 11-09-2001).]
[This message has been edited by ForrestB (edited 11-09-2001).]
Firstly it all depends on what is meant by a switch barrel. ForrestB has discussed the take down rifle.
Excluding take down rifles, switch barrel guns are most frequently found on either benchrest rifles or other heavy barrel accuracy guns.
In these guns, the barrel can be removed without taking the rifle apart because of the very wide barrel channel.
However if you have one of those "rubber" type synthetic stocks like on the factory Rem and Model 70s you can make the rifle so as the barrel can be removed without taking the gun apart.
However, you usually have to remove the scope and this is where detachable mounts are of use.
By having the right clearance and shape of the clearance around the back end of the barrel and in combination with the flexible stock, you can change barrels OK.
I would not regard the Mauser as the ideal action as they do not always shoot at their best unless there is an inch or so of bedding under the back end of the barrel and that has obvious problems if you want to change barrels and not have to rebed the rifle.
Rem 700s are OK if the recoil lug is pinned and the Model 70 is ideal.
As to cost, it is simply two or more chambered barrels and an action wrench and barrel vice.
Switch barrel rifles are not really about changing barrels in the field unless you are in a varmint situation.
Basically the are simply a rifle with one or more spare barrels of similar contour.
Some people also have both the 30/06 and magnum bolt face bolts.
Mike
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