I have been trying out different 22 cals in 30 cal sabots in 308, 300 win mag and 30-378 (52g Match at 5000+fps!). Would like to share experiences...best accuracy with 52g seems to be in 4600-4700fps range, with groups around 2" at 100. Pushing much faster than this seems to destroy accuracy quickly, but 5000fps is definitely hell on a milk jug.

Where do you get your sabots? I have always wondered how they would shoot. Hitting a ground squirrel with a bullet moving at 5000 fps would me a something else.

I get them from a place that advertises in the Shotgun News..they are like $60/1000. Can't remeber the name now. Made of plastic but work well. Cool part is that you don't get copper deposits (duh), nor any plastic residue either. The barrel is very easy to clean.

The muzzle blast is fierce..you can fill the case more with powder as the sabot is so short it barely fills the neck. Easier to load as well, you don't resize the neck with a die..leave it in as fired condition and simply squeeze in the sabot with the bullet in it.

What's interesting is that it tends to take a lot more powder to generate more velocity. ex: full case 308 will push 52g to 4500, 300 win mag to 4800, 30-378 to 5000+. Doesn't seem like alot of change and it really isn't, but for affect you can't beat the blast of the 30-378. Actually I got to almost 5400fps with 40g but the bullets disintegrated shortly after leaving the barrel, one happened before the chronograph screens and took it out..needed a new one anyway Some limits need to be challenged....had to see if I could just a few more fps before bullet failure. Actually I had read an article somewhere that at 5000fps the bullet will leave a hot streak in the air from the extreme resistance it encounters in the atmosphere. I may use barnes solids and try again. BTW, the recoil is nothing to speak of. The muzzle blast has more impact on you.

Try here http://www.eabco.com/barels01.html