I am looking at a Lo wall in 45-70 that I may buy to rebarrel.

My question is what issues will I get into by rebarreling this rifle into a caliber with a smaller case head diameter than the 45-70?

It will likely be a more standard case head diameter, .257 Roberts or .260 Rem.

The Low Wall chambered in .45-70? What I know, is, that the Browning Low Walls in the last years, were never chambered in .45-70. Only the High Wall was/is available for this round.
But rebarreling is not the problem. You need an new extractor.

Martin

I don't know why I called it a low wall. Must have had it on my mind. Thanks for the info.