Command Arms Accessories has had the RONI carbine conversion for the Glock pistol available for quite some time, but that adapted an existing handgun to a shoulder-fired weapon. Due to the barrel length of all Glock pistols, this required NFA paperwork be done on the handgun, as it was now a “short barreled rifle,” or SBR.
Enter the RONI C G2 17, which is a longer version of the old RONI and is designed specifically for the Glock 17. It also includes a 16″ barrel, which CAA says will obviate the need for making your Glock an NFA item. The conversion is $499.
I have fired a “small” RONI with a Glock 17 converted to full auto, and can confirm that it is a very fun gun to shoot. The new, big RONI will bring similar levels of semi-auto fun to those who want it. As a serious defensive weapon, I do not know that it has many advantages other than being quite light. Thus, it might be a good choice for those who physically cannot wield a 6-7lb AR or shotgun for any length of time.
However, the cost of a Glock 17 and the RONI with 16″ barrel will be about $1000, and there are many long guns in more effective calibers which may be purchased for less.