GEORGE WALLACE says: In a word, no.
I remember hearing of a shooting match some years ago between riflemen and pistol shooters. Admittedly the pistols were designed for long-range accuracy, but they still had barrels only half the length of those on the rifles. My informant told me that the pistoleros whipped the riflemen soundly!
A longer barrel will, up to a point, give more velocity but accuracy is controlled by the quality of components in firearm and ammunition and by the way they are put together. Short barrels also make a much louder bang and produce more recoil, but that’s another subject.
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