To my knowledge 120gr is the biggest you can get for the 25.06. If you want something bigger than thatyou should step up to a 270 or a 30.06. My favorite bullet for the 25.06is the 110gr Nosler Accubond. It's very accurate and it's performance on game has been excellent for me.
When I was shooting a 25-06, I liked the 115 gr. bonded bearclaw. The heaviest bullet I've seen for the 25-06 was a 122 gr. softpoint. I can't even remember who made that one.
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