Originally Posted by pyroducksx3
I have heard the opposed. As far as I'm aware the stw actually has a little freebore which causes significantly faster erosion and was a great factor for a member here creating the 7mm practical (7-300 win mag with modified shoulder I believe)........
The 7 STW's throat length will vary depending on how thw reamer is cut. However, it has nowhere near the .375" of freebore of the current proprietary Weather chamberings. Also, freebore doesn't cause throat erosion. If anything, it would lessen it because the rifling is farther away from the hot gasses upon firing.
The short neck of the 7mm Rem Mag coupled with it's shoulder angle allows the hot gasses to sandblast the neck of the chamber and accelerates erosion. The longer neck of the 7mm STW prevents that. That is the "turbulence point" theory and is an attempt to explain why the 7mm STW and 6mm Rem have better throat life than the 7mm Rem mag and the 243 Win, respectively, even though the 7 STW and 6mm Rem have larger capacity cases.
The question isn't whether or not the throat lasts longer with the 7mm STW and 6mm Rem, that has been observed for a long time. The question is why, and turbulenece is an attempt to explain it.