Should work.
I use O-1 drill rod for things that require a representation of bore axis, or a heavy clearing rod, or for slugging, etc...
There's always a fraction, metric, or letter size close enough to be 'close enough.'
They do come in handy...
That's a .250" ground rod, in a 6.5mm barrel (.256" bore, I believe), and an 8.8" .30 caliber suppressor.
