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You can also speak to Kynamco who make such things plus Lapua factory subs are readily available, I usually have a few boxes in the safe for a rainy day.

Thank you guys, I was going to PM a couple of you for more info but that facility is not available to me at this time. Can anyone point me to their gunshop where they recently bought their stock from. I can then follow up. The Kynoch website is really interesting. I expect there is some great history there.

You'd probably be best going direct to HPS; they will deal with the public and you can pick stuff up from them (or they'd probably courier it to your RFD at your cost).

Just a thought

All of the .308 subs I have dismantled had heavy bullets (the Lapua one had a totaly different ogive more akin to a HESH round).

The optimum aerodynamics of a subsonic round are very different from those of a trans- or super sonic round, hence the different nose shapes. With a sub-sonic round, a 'shock'wave propagates ahead of the bullet (hence termed 'detached') whereas with a trans-sonic round the shockwave is attached, i.e. actually in contact with the tip of the bullet. With a supersonic bullet, the shockwave is attached and laid back along the bullet. Wave drag and boundary layer phenomena are different for all three cases, and thus the bullets require different shapes for best performance. Schlieren lens photographs show the different flow regimes quite well.

meles meles wrote:The optimum aerodynamics of a subsonic round are very different from those of a trans- or super sonic round, hence the different nose shapes. With a sub-sonic round, a 'shock'wave propagates ahead of the bullet (hence termed 'detached') whereas with a trans-sonic round the shockwave is attached, i.e. actually in contact with the tip of the bullet. With a supersonic bullet, the shockwave is attached and laid back along the bullet. Wave drag and boundary layer phenomena are different for all three cases, and thus the bullets require different shapes for best performance. Schlieren lens photographs show the different flow regimes quite well.

Similar to a wing right?

Interesting.

What I was driving at was that in order to work there was more to it than just down loading and the bullets need to be stable in an entirely new mode. Built for purpose and to suit the rifle.

Nuff said, I am out of my depth as I was just looking at the various components, cutting out crack, flying slow and stable which just suggested a heavy.

take care.

M

Yes, similar in many respects.

Note that the subsonic pistol bullet has a blunter nose than the rifle bullet. It doesn't matter too much as the detached shock wave ahead of it is elbowing the surrounding air out of the way. The supersonic rifle bullet has to be quite pointy and streamlined as it, rather than the attached shockwave, is doing much of the pushing and shoving against the air in front of it. Note it has a second shockwave originating at the rear cannelure, and a third emanating from the turbulent wake behind it. The rifle bullet needs to be boat tailed to try and reduce / control these effects, whereas it doesn't matter nearly so much in the slower pistol bullet. The wakes are different betwixt the two bullets too: note the shape and relative turbulence of each. The pistol bullet can afford to be blunter and have a greater cross section (and hence mass) as these are far less detrimental in the subsonic regime.

Slow and heavy nearly made the American Buffalo extinct along with the premium put on them so as to make sure the American Indians lost their main supply source.

These days, that could be shortened to

"Slow and heavy nearly made the American extinct"

This is the Lapua 200 gr subsonic bullet that Laurie and Ovenpa refer to in their posts. The 7.62 mm cases have been deliberately stained for identification.
You could give Sporting Services a call regarding stocks of subsonic ammo, but in the long run it will pay to reload.