There is no one size fits all Democrat. Some Democrats do hunt so yes, there are some who own hunting rifles. There are also some who feel the need for personal protection, or who just like going to a Shooting Range, so yeah some will have handguns. There will be very few who actually own more than that.
The most common mass collectors, especially of military style weapons, are either wealthy white men who see it as a status symbol, or those who are either thinking of using them against other people or are of a militaristic mind-set.
The demographics of gun ownership
Besides demographic differences, clear partisan divides emerge when it comes to gun ownership. Republicans and Republican-leaning independents are more than twice as likely as Democrats and Democratic-leaning independents to say they own a gun (44% vs. 20%). This partisan gap remains even after controlling for demographic differences.