130 ELD & XBR or AR-Comp

[SCJim]

not sure if anyone has mentioned the Hornady manual data yet. For 8208 it has a low of 24.4 and a max of 26.2 for the 130 ELD match. Usual disclaimer about start low and work up, what works in one rifle may be dangerous in the next etc

[Gtscotty]

Weighing in on Post #29

Velocity is not pressure but it is a pretty good proxy. In the absence of being able to directly measure pressure (no strain gauge) then a popular choice is to use velocity. QL and manufacturer load tables list both the velocity and pressure for a particular load and barrel length so it is not unreasonable to use this as a guide for one's own loading. With a chronograph shooters can mimic manufacturer and computer simulations and have confidence that their pressures are similar. Again, without a strain gauge you are left with a few choices; computer simulation, manufacturer load tables, fellow shooters on forums, reading spent cases like tea leaves, feeling the recoil in your shoulder, loading until something breaks. or a combination of these.

As far as publishing being more credible than a computer simulation like QL is concerned - anyone can publish. Every time one of us shares a load on this forum they are publishing. A few forum members got together and published a book with loads. Manufacturers publish online and physical books. What decides whether a posted load on this forum is more credible than Hodgdon's manual is the reader. The same goes for a computer program vs. a published loads. I use them all and they complement each other. I've used QL for several years and have come to believe it is as credible and more precise than a manufacturer's website (which list only a few loads and for a particular barrel length).

+1 Pretty much exactly my thoughts. Without a strain gauge, velocity is the best indicator of pressure in an individual rifle that you can get. Brass damage can be suggestive once you get used to how a rifle with a certain gas setup treats brass, but it's not nearly as good an indicator as velocity. When using QL you obviously need to true it to a span of measured velocities from your particular rifle before you use it to try and interpolate pressures. No one would recommend that folks just bang some numbers in and do whatever the computer says. That's not how you use mathematical simulations, although that seems to be what some folks in this thread are assuming.

It's good to have published load data in the mix, but it doesn't give you license not to do your due diligence or use your brain, you still have to do the work-up in your own rifle to make sure velocities are reasonable and there aren't any glaring pressure signs. My latest .308 has a tight chamber and shows higher velocities than books predict it should for a given load, it also starts showing pressure on cases about a grain early.....funny how that works out.