To remove very tight screws there is a little trick that works very well most times! Simply place the barrels in a freezer for about an hour, and the screws will usually turn out easily, because the screws shrink from the cold! This is an old trick we learned years ago when the big magnum pistols became popular for hunting! The screws tightened at room temperature tended to back out from recoil in the cold weather of the winter hunting fields. The fix was to tighten the screws at room temp, then place the pistol in the freezer, and re-tighten while very cold. The reverse of this is to freeze a firearm to remove very tight screws as well!

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