My first rifle was a Tang Safety chambered in 6mm Rem so the 257 Roberts will fit.
Remington takeoffs make an inexpensive way to rebarrel a Ruger tanger. There is minor machining required as the Remington's threads are 1.050" while the Ruger's is 1". After the recess is faced off, the diameter is reduced to 1", shoulder moved forward a bit, and it is threaded for 16 TPI.
If one chooses a the correct size reamer it can clean up the existing chamber. It may require some setback. When my 6mm Rem wore out, I went to a local gunsmith, the late Harry Lawson. He suggested the 284 Win. He had quite a few Remington takeoff's in 7 Rem mag. That rifle is on its third 284 barrel. Since that time around 40 years ago, I do my own lathe work and own the 284 win reamer. The latest barrel is a 24" Rem takeoff that was a 7-08. Finished barrel is 23.5"
I mention this because the SA Ruger Tang Safety will fit and feed the 284 win fast or slow with no modifications what so ever. I liked how this package worked so well that I ended up with a second SA tanger and set that up for the 6mm-284. FYI the 6mm-284 cleans up a 243 Remington takeoff chamber very nicely after removing the bolt recess and moving the shoulder forward.
As a final note: Many years later I had Joe at Lawson's lengthen that 284's mag box so it will fit and feed a cartridge with an OAL of 3.050". Just letting you know that is possible.
Good luck on what ever barrel you put on your SA Ruger rifle.
