Rechamber from 35Whelen to 35 Whelen Imoproved?

[Redie Fredie]

What would it take to rechamber a A&B Mauser Barrel in 35 Whelen to 35Whelen Improved? Barrel is  installed, would it require removing barrel?
Would it be as pricey as a rebarrel?
RF

[trotterlg]

When an "improved" chamber is cut, it is slightly shorter to the neck/body junction so that standard non-improved rounds can be chambered and shot to form the improved brass.  To do this, the barrel has to be set back some, to do that you have to remove the barrel.  Only exception is with rimmed cases like the 30-30.  Larry

[mauser98us]

According to Ackley's books it is reset back one thread.I love my improved version,eve tho I'm not sure it really spices it up that much. It was more of an emotional decision for me than anything else. It really looks cool

[iiranger]

I had a gunsmith explain to me, good friend, that the "one turn" talk was so that the sights would end up back on top. If there are sights...-??- Otherwise it could be a whole lot less, but takes a good man with good measuring tools to figure how much. 1/2 turn? 1/4 turn.

You want real tight head space BECAUSE usually the rimless Mauser headspaces on the body/ shoulder junction. With the Improved, the factory cartridge has to headspace on the base of the neck because you cut away the shoulder for the first shot. It has been done at home without pulling the barrel BUT I cannot recommend that. Your gun, your bucks, your call. Luck.

[gunnut69]

If this is done without the setback one looses the ability to fire standard 35 Whelan rounds to form brass for the improved version.. but... you knew it was coming didn't you? The question is can acceptable brass be made without danger and the answer is yes.. Cast bullets can be seat to protrude farther to allow the headspace to set on the bullet extending into the throat(seating them backwards will accentuate the effect) and fire with a fire forming charge of fast burning powder.. The shorter necked version(??brown?? whelan?) requires such shenanigans as it cannot be fired with standard Whelan ammo to make brass. BTW cast bullets make excellant loads for fireforming.. Of  course there is a down side. When the rifle passes to it's next owner they must be aware of the situation and the cases are more difficult to make.. Still how many cases do you need for such a rifle. I would reccomend the longer Brown version () and have fun..

[quickdtoo]

You can also form a false shoulder by necking up to .375", then run them thru a full length die to push the false shoulder back just enough to eliminate the excess headspace, then fire form. I just did that for my 35 Whelen "Improved-Improved" H&R which the barrel can't be set back on, there's just too much headspace to shoot factory ammo once it's rechambered. 

Tim

[Redie Fredie]

Great info, thanks all!

[S.B.]

You can also form a false shoulder by necking up to .375", then run them thru a full length die to push the false shoulder back just enough to eliminate the excess headspace, then fire form. I just did that for my 35 Whelen "Improved-Improved" H&R which the barrel can't be set back on, there's just too much headspace to shoot factory ammo once it's rechambered. 

Tim

Sounds like a lot of work for a conversion?
Steve