Advice about pressure signs

[StoneHendge]

I finally got home to look at some data.

Hornady factory 123SST loads chrono at 2548 out of this barrel with no pressure signs. The 123 EDLM/AR Comp load that caused me to start this thread chrono'd at 2498 fps with an ES of 10 for a 5 shot load. Using my Hornady comparator these measure 1.670" to the ogive and I hit the lands at 1.694" so definitely not into the lands.

I don't think that changes any thing mentioned previously. I'm still likely over pressure for my gun. The thing that has me confused, well more confused than everythign else anyway, is that I don't think I had pressure signs running my carbine lower with H2 buffer. I don't think I started chewing up brass until I went to the Magpul PRS stock with rifle tube, spring, and buffer. That's easy enough to test by swapping lowers next time I'm on the range.

Turn off your gas COMPLETELY and take 5 shots. If there are pressure signs, then the pressure signs are caused by pressure. If not, then what you are reading as pressure signs are caused by timing. You may still be overpressure (I won't get into the discussion about some German dude's software) but your downside is likely limited to a broken bolt lug. I've found that timing issues will ultimately result in a broken extractor and that extractors can break at very inopportune times and are not often easily removed from a barrel extension in the field (along with bolt lugs).

Hornady ammo likely uses CFE 223 and/or LeveRevolution which is slower than AR Comp and will have a later pressure peak