Why don't you have the 270 gibbs it was the most popular of them all wan't it? Ya mine shoots a 130 tsx barnes at 3375 over 65 gr of reloder 22 and cci200 primer out of a tc encore pro hunter. This load works in my gun but recommend orking up to that load. So how does the 25 gibbs shoot and what load. Do you have any of the reamers for those cartridges?
Could you post a pic of the Gibbs next to a normal 270 Win? I would like to see the difference in shoulders and neck.
"Enter through the narrow gate. For wide is the gate and broad is the road that leads to destruction, and many enter through it.  But small is the gate and narrow the road that leads to life, and only a few find it.
If you find your self in a fair fight, your tactics suck!- Marine 1st Sergeant Jim Ryfinger
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arguing over the internet is like the special Olympics....even if you win, you are still...special!