No worries. Everyone's input is welcome, so no need for you or anyone else to drop out of the conversation. Perhaps because I know Brad, I simply didn't take his response in the negative way you did. I really don't think he meant his response to have a negative tone.
In response #1, he recommended a 6.5 - 7.0 twist rate, which I think covers the OPs question about as well as it can be at this point. However, I'll add in a little bit of speculation here: a 7.0-twist clearly has worked well for a number of people. However, some are using slightly faster twist rates such as 6.8 (myself), 6.7, or even 6.5, in order to get a [predicted] Sg of 1.5 or greater. The downside to the slightly faster twist rates may, and I repeat, MAY be a higher propensity for jacket failures. Unfortunately, the underlying cause(s) of the occasional jacket failures people have reported here is still unclear. My best guess is that the increase in twist rate (below 7.0) is a contributing factor, even if it's not the sole cause. It's possible that the slightly faster twist rate barrels, in combination with other factors such as temperature, velocity, type of rifling (lands/grooves), barrel cleaning procedure, etc., may be closer to the whole story.
So at this point, I'm not sure I would recommend anything below a 7.0 twist to anyone wishing to run the 90s. You may be giving up 2-4% [theoretical] BC, but I can tell you from personal experience that a jacket failure [0/10 points] in an important match is far worse. I've shot the 90s out of a 7.0-twist out to 1000 yd for several years now and never felt as though the I was giving up too much wind resistance (BC) due to the slightly below-optimal twist rate. Frankly, a more important issue at 1000 yd IMO is keeping the ES/SD as low as possible. I typically see ES values in the 15 fps to low 20s. I am rarely able to get the ES below that on a reliable basis, which will ultimately give more vertical at 1000 yd than a .308 load with an ES below 10 fps. I recently also went with a 6.8-twist on a new .223 build for the exact same reason the OP asked about. As Brad noted, there seem to be many more people using the 90s currently, and the number of posts asking various questions have also increased noticeably. For that reason, I don't always respond to every single 90 VLD post if someone else has already covered the same information that I might have put in a response. This was one of those cases. For future reference to anyone interested in shooting the 90s, simply do a search here of "90 VLDs". You will find a wealth of information from various shooters from the the past several years. As far as being one of the "top shooters in the U.S.", I have enjoyed a modest amount of success at the local/regional level, especially shooting the .223 with 90s. However, there are so many F-TR shooters in the U.S. far better than I am it's not even worth thinking about. I do have a bit of expertise shooting the 90s, possibly because I started working with them several years ago, before they had caught on to the extent they seem to have done currently. But the real innovators on using the 90s are people like Laurie Holland, who is a member here at A.S., and Robert Pitcairn. These folks were working out how to shoot the 90s many years ago, which made life much easier for myself and others when we moved into 90s territory. I view it as akin to standing on the shoulders of giants.
In response to the OP's question about the 80.5s, the answer is "Yes", if you're using PTG's 223 Rem ISSF reamer (0.169" freebore). The 80.5s will be fairly far out in the neck if seated at about .020" off the lands, but not so far as to be a deal-breaker. I have never tested the 80.5s farther off the lands than about .024", but it is a tangent ogive bullet and seems very forgiving with regard to seating depth. So it might be possible to tune (seat) them even farther off the lands and regain a little more neck/bearing surface contact, if they seem too far out in the neck.
