Altering The Caliber
The most complete transformation is offered by the caliber conversion sleeve. These include not only a new chamber, but a new barrel as well, allowing a smaller diameter bullet to be fired. These sleeves may be significantly longer than a loaded cartridge, if the length of the parent cartridge is not sufficient to provide the desired performance. Unlike the other types of cartridge conversions, this type incorporates rifling to stabilize the bullet; the other types rely on the rifling in the firearm's barrel.
Read more about this topic: Caliber Conversion Sleeve
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