You can do it, but there's a process and money involved. As has been said above, file the paperwork with ATF, pay the $200 fee, and then enjoy it as it is until you get your approved tax stamp in a "few" (7-8 last i checked) months, and THEN, change it into the configuration you specified on your papers. Yes, they will want to know a specific barrel lenght, caliber, overall lenght, etc, etc. I hate to say it, but by the time you buy the rifle, and pay the tax stamp, you could have bought a contender and been shooting it for several months. This is why I have both. My H&Rs are staying in long gun configuration and the Contender (bought as a pistol) gets used as the handgun. Boring, I know, but cheaper, quicker, and (legally) safer in the long run.