How can you improve the accuracy of a 257 Roberts Winchester Model 70 Featherweight if you have tried new scope bedding different grain bullets and reloading combinations and the barrel is good?

Answer

I too have a Win Mod 70 Featherweight that I purchased new in the late 80's (non controlled feed action). The best I have ever been able to get it to consistently shoot is about 1 1/4" and that is with certainly handloads. The skinny, lightweight barrel is really a roadblock to getting MOA accuracy.

However, if you are having trouble reaching at least 1 1/2" after all of the things you have already done, you might want to consider recrowning the barrel.

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There could be a dozen causes for your 1-1/2 inch groups but it is probably not the barrel crown. You can look at the crown and tell if it is damaged. If you do not hand load, buy some Federal or Remington or Winchester 100 grain ammo and go sight in and live with what you get. Your gun is not a target rifle. 1-1/2 inches at 100 yards is 3 inches at 200 yards and is perfectly acceptable for a hunting rifle. You can't hold better than that shooting offhand anyway. If you do hand load, try a Barnes 100 grain TTSX bullet over 35.0 grains of IMR 3031 and seat the bullet to 2.830 inches OAL. Your gun probably has a 1 in 10 twist rate and that twist rate will usually not stabilize bullets over 100 grains. Stop worrying about your group size and just go shoot. If you miss, it's not the gun's fault.