So I won another mosin action. It’s in great shape. There is nothing with it. So I have a great canvas to work with. I was wondering about 35 whelen. It’s based on the 30-06 round. Since I’m going to have to have a barrel made what do you think of the caliber?
I know they made them in 30-06. So I know they can handle that. ( I’d made proper that is).
It is not always a question of receiver strength. However, those made during the early 1920's during the Russian Revolution are suspect on being properly heat treated due to wartime conditions and the need for something to go bang. The 7.62x54r is a fine old cartridge in its own right and as efficient as a .30-06 when it comes down to it. It will handle a gamut of bullet options from light high speed to heavy and slow bullets and works well with cast bullets. So a conversion to a 30-06 would not gain you much if anything over a properly loaded 7.62x54r.
You might want to read a thread of recent THR comments on a recent thread dealing with the 35 Whelen in rifles--I believe the conversion receiver would have been a Mauser. The general consensus seemed to be that it was not enough of an upgrade from a .30-06 to be done.
Bannerman made those 30-06 conversions and those things are universally considered unsafe because they did not set back the original barrel and the Russian issue cartridge is wider than the .30-06 at the rear of the cartridge. Their accuracy is not great either due to variance in Mosin barrel bores. The rimmed Russian cartridge helps seal the back of the chamber from gas events and moving to a rimless defeats this and can result in the rear of the cartridge being unsupported. Rimless cartridges need better venting than the Russians did simply because a gas event in a Mosin lacks good gas handling in that case.
In addition, the Mosin is a rimmed cartridge and designed for such so the .35 Whelen as a .30-06 derivative require quite a bit of work on the magazine, a new barrel (often an 1903 barrel was altered to work--not really worth it now given the price of originals) with extractor cuts, bolt head changes along with extractor issues. Mosins have had feeding problems with their rimmed cartridges as the feeding system is designed to prevent rimlock--conversion feeding might be unpredictable due to cartridge family variations between the .30-06 family and the 7.62x54 r family.
These are not Mausers that often were made for dual use and ease of cartridge conversions within cartridge families. The Mosin rifle was designed around the cartridge and not vice versa and they were not designed for dual sporting/military use.
You will have the best luck with either necking up or down the existing 7.62x54r cartridge if you really want to convert it as an easier job. I believe the there is a 6.5 necked down version used as a sporting cartridge in Russia and I suspect that someone has necked one up but both conversions would require new barrels.
Other folks with more money and time do things like convert them to .303, (one recent poster had a rare 8x57 Mauser conversion done by an arsenal but has no plans to fire it due to safety reasons and its rarity), Austria converted some to their WWI cartridge and I'm sure that Germans may have done the same as last ditch type firearms.
If you want an idea of what can be done, Reid Coffield redid a Mosin (did not convert the cartridge though) along sporter lines. You will find it in the Shotgun News Compilation of Gunsmith Projects published about 2012 or so. Might give you some ideas.
