I'll restate, the particular calibers mentioned are designed to be fired from at least a 20" barrel/ If you want a short barrel brush gun a different caliber with a faster burning powderwould be a better choice. At 100 yards you may not notice a change, but at 300 yards should the opportunity present itself there is a substantiallack of performance in the extreme short barrels, better to have and not need than want and not have.