I use the LSS chassis for my little 308s, smallest being 10 inches, although optimum without losing too much velocity without going to crazy fast burning powders is 13 inches. The latest 13 inch got to 2750fps with 150s, which is perfectly fine for well, anything really.
The 10 inch gets the 150s to just over 2550fps. Rem700 action, trueflite ultramatch, with a Sightron s3 6-24x50 sits at 3.2kg.
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