Headspace and purging in secondary

I have a bunch of 6 gallon carboys, but I’m making 3 and 5 gallon batches of big beers. Common teaching is that when aging for very long, one wants to minimize headspace. When I transfer the beers from primary to the 6 gallon carboys to let them bulk age, will the off-gassing during transfer protect them even in the large headspace? Additionally, if I purge the headspace above the beer with CO2 from my kegging setup, can I leave them for months without worrying about oxidation the way I normally would with a lot of headspace?

You may be OK with just the out gassing from the transfer. But sense you have a keg set up, it will be easy to give the carboys a shot of CO2 for good measure.

I don’t see why there would be any issues with the carboy being 1/2 full verses 95% full in regards to aging time.

Do you have extra keg that you could skip the carboy aging and just put them in kegs? Add 30psi and forget about them.

I may go with the keg option, as I have some extras right now. Thanks.

I vote for the keg option. Less headspace plus easier purging equals win win. A used corny doesn’t cost much more than a carboy either.

That said, you would probably be fine in the carboy.