I've noticed that there IS a difference in alloy. Some (from Ferrocerium.com) are more smooth and a bit softer, then the LMF steels.
...Soft firesteel= big curls of steel and harder to get a spark. But if they ignite, the curls do last longer when burning/glowing.
Hard firesteel= hard to scrape and hard to get good "thick" long lasting sparks...
Oh crap... The ones I bought from eBay seem to come from ferrocerium.com. I asked the guy I got them from if he had any more sizes and he told me that he didn't have any at the moment, but that he could get almost any size I wanted. So he must be getting them from ferrocerium.com or any other company who sells blanks.
I had a hard time drilling them but I was using a hand drill and my drillbits were not the best ever, so that is more of my fault than anything else. I noticed that when making a lot of force to scrape them (you know, put it in the ground, push hard with the scraper and do short powerfull strokes) I sometimes get big curls of metal that don't ignite. I don't get spark showers like the ones I have seen in some youtube videos. I have tried anything from the square faces from my Leatherman screwdrivers to the spine of my knives (F1 included) and of course the well known bimetal hacksaw blade. No way of getting huge showers.
I just bought two Barkies and both come with a firesteel loop. I think I am going to get some LMF Fire steels to fit them. They are sized for the ARMY model, right? I know LMF makes the little SCOUT model and the bigger ARMY. I just want to be double sure to be getting the right ones!
Mikel