Sorry if it has been mentioned and I missed it…Nailguns as sold in the US have a safety interlock that keeps the gun from firing unless it is firmly pressed against a surface. They are, in effect, contact weapons.
I’d try a brush hook like this. Or better yet, two.
No report, actually. I just saw an old thread had resurfaced, and that’s usually worth investigating. And then once I deleted the spam, it would look like you had bumped it, so I was forestalling any zombie jokes.