Well, somebody probably tried this before, but I just "discovered" a relatively inexpensive light mount:  The Tac-Star clamp (image from www.midwayusa.com).



I had this on my shotgun using a Maglite (don't ask)...when I made a new mount to put a G2 on the shotgun, I reversed the clamp & tried it on my Tactical Lightweight bbl from J&T.  Clamped the G2 to the bbl perfectly!  The bbl diameter is approx .725".

The mount is about $22 through Midway, but you might be able to get it cheaper elsewhere.  There are different styles/sizes too.

Just one more way to skin the cat...

--Otter

How about a couple of stainless hose clamps if you're going REAL cheap.

Why waste money on hose clamps?  You can probably find some paracord laying around, right? [;)]

Actually, on the shotgun I used a quick-detach scope ring on the mag tube, and used a hose clamp and 2 fastener sets to attach a weaver base to the Surefire.  A little black spray paint, and viola! Under $10 for a solid, detachable light mount.  Perfect for a home defense gun.

--Otter

I hear duct tape works good too. Just ask Sniper Wolf.

Free - ranger bands.

Cut up dead innertubes.  Free from bicycle shops

Yep...ranger bands, duct tape, zip ties...all work.  I was just experimenting with different ideas to find something a little cleaner looking, without spending a fortune on the stuff the "big boys" use.  

That stuff is appropriate for the professional, but not cost effective for the rest of us.  Just trying to keep it inexpensive without the jury-rigged look.

--Otter

I've got a set.  They are solid as a rock.  I have them mounting a TACM III light on the barrel of a Colt 16in HBAR.

ColtRifle:

A set of...which?

--Otter