I have a forbes 25-06 that Melvin Forbes worked over with a new barrel
recently i noticed that one of the nickel cases i have been shooting in it had the nickel separated with a small line around the case, so i opened the case up to find the start of a case separation issue....to my knowledge these have only been resized in the collet die i have ...seems like this couldnt happen when using this die ....thoughts
Likely brass stretching on first firing in that chamber. If you want to avoid it, you could neck down .270 brass in a full length 25/06 die and form a false shoulder so that it chambers with a slight crush fit. Neck is longer on .270 so you would have to trim it as well.
Could do the same with 25/06 brass by first necking it up in a .270 die then proceed as above.
John