Imagine that...

[Digital Dan]

Been doing a bit of exercise of late in fire forming cases for a K-Hornet. Older gun with a .223" groove. The Lyman225438 is cast with 50/50 WW/Lino, sized to .224", tumble lubed and dusted with a blend of motor mica and graphite.

Initial fire forming has been done with a small charge of 700X and is reasonably successful with adequate accuracy, velocity in the range of 1700-1800 fps. There has been no leading or other unpleasant sideshows.

Out of curiosity I thought it might be interesting to see if I could precipitate leading at higher pressures, so a half dozen loads were assembled with 2400 and fired, velocity in the 2300-2400 fps range. No leading, not a trace.

A bullet recovered from the sand:

http://img.photobucket.com/albums/v298/muddler/Guns/Fireform2_zpslqzudo3x.jpg (http://smg.photobucket.com/user/muddler/media/Guns/Fireform2_zpslqzudo3x.jpg.html)

[Hickok]

I really like that boolit in my Hornet.

That velocity is fast. Did you get any accuracy at that speed or was it just a test for leading/velocity?

[Ballistics in Scotland]

If it isn't for game on which you don't want fragmentation, and if you don't mind the little bit of extra powder it costs you, it is well worth a proper testing for accuracy. Inaccuracy and leading aren't just things which coincidentally happen together or separately. Leading is one of the main causes of inaccuracy, and you are without it so far.

I would make it a thorough test, though, with a moderately hot barrel. These things are liable to be inconsistent, and if it is going to play up on you, the shot of a lifetime is when it is going to happen. Admittedly you don't think of a K-hornet as the sort of rifle which puts you up there with the people who have been and seen. But a varmint briefly showing from the eyelashes up at a hundred yards and saying "Yah boo!" could still be it.

[Digital Dan]

Some time back I received some advice here on the board on the topic of fire forming bullet alloy from Larry Gibson. The primary purpose being to form the brass w/o wasting what has become a somewhat valuable commodity, namely jacketed bullets. They have worked well for that purpose w/o breaking the bank. With the load mentioned above with 700X they have been shooting 2 MOA with some reliability, better than I had expected. Having a supply of formed brass at this point I decided to have Hornady make me a hydraulic form die to save a little time and repetitious travel. They need three formed cases, not sized.

Having read commentary here regarding accuracy degrading with LLA as the velocity climbs (not my experience), I decided to see what happened at a bit stiffer charge. Accuracy was not tested, but I will do that down the road with the remaining 15 rounds so loaded. Dunno that I will or won't use that bullet/load down the road, but my gut says it will go faster w/o malfunction. Maybe I will, maybe not.

http://img.photobucket.com/albums/v298/muddler/Guns/IMG_1959_zps835db523.jpg (http://smg.photobucket.com/user/muddler/media/Guns/IMG_1959_zps835db523.jpg.html)

http://img.photobucket.com/albums/v298/muddler/Guns/IMG_1962_zps52cfbd13.jpg (http://smg.photobucket.com/user/muddler/media/Guns/IMG_1962_zps52cfbd13.jpg.html)

It's entirely possible that I'll alter the alloy down the road for the sake of curiosity.

[Ballistics in Scotland]

The other possible snag is that a cast bullet receiving that kind of whack from behind will upset, and shorten its nose. It might not change its shape quite the same on all sides, making it unbalanced. But don't give up on that account without giving it a fair trial.

[shooter93]

Ken Howell's book on designing and forming cartridges has a good way of fire forming brass without using any bullets at all. It works well.