Quickloads ?? Is it worth the $$

[Carey Farmer]

In the pressure report image posted above, if I'm looking at this correctly, T4 projectile has 7% higher muzzle energy than T2, despite T2 impulse work (area under the pressure curve) being 35% greater than T4. I think that suggests there may errors in the pressure vs time measurements. Or perhaps in the muzzle velocity measurement.

I would also comment that for a given powder charge weight, "book" chamber pressures can be quite different for different bullet constructions. This is certainly the case with Hodgdon's reloading data center. And one sees that pretty clearly (via the typical pressure signs that handloaders watch for) when shooting Partition or Barnes bullets vs. Bergers.

Finally, even though very few of us measure our handload pressures directly, I have a relatively high level of confidence in the repeatability of ejector marks on soft-headed (Norma) brass as an indicator of pressure. And as I remarked earlier in this thread, my experience is that QuickLoad is pretty good at predicting what load will result in ejector marks (after tuning to measured muzzle velocity in lighter loads).

 

[Darkker]

While Pressure Trace shows a burn's form, unless using an official test barrel (SAAMI), the hard numbers could be as wrong as QuickLoad estimates.
Right?
The alternative to either (manuals) gives us nothing.

No, because of the calibration in a PT. You have to cast your chamber and carefully measure it out. Once those numbers go in the system, you don't get to change them like everyone does in QL. Then you order SAAMI reference ammo, carefully measure it, record and fire, then carefully section and measure the case again. Now you have a precise correction from the standards, to your chamber.

In the pressure report image posted above, if I'm looking at this correctly, T4 projectile has 7% higher muzzle energy than T2, despite T2 impulse work (area under the pressure curve) being 35% greater than T4. I think that suggests there may errors in the pressure vs time measurements. Or perhaps in the muzzle velocity measurement.

I would also comment that for a given powder charge weight, "book" chamber pressures can be quite different for different bullet constructions. This is certainly the case with Hodgdon's reloading data center. And one sees that pretty clearly (via the typical pressure signs that handloaders watch for) when shooting Partition or Barnes bullets vs. Bergers.

Finally, even though very few of us measure our handload pressures directly, I have a relatively high level of confidence in the repeatability of ejector marks on soft-headed (Norma) brass as an indicator of pressure. And as I remarked earlier in this thread, my experience is that QuickLoad is pretty good at predicting what load will result in ejector marks (after tuning to measured muzzle velocity in lighter loads).

No, that's not remotely what it says.
But I appreciate you proving my warning to others.

'Partitions and Bergers' aren't different construction, in the discussion of pressure differential; but Barnes would be. The nonsense about bearing surface that everyone likes to parrot, doesn't exist in the terms they claim it does. Just like the FlatLine crap that was going around several years ago.

So to tie into your signs claim about head swipe.
I'm not saying Norma never had a bad lot sneak out. But the actual pressure tested truth, not prayer, of the matter. Is Norma isn't even remotely close to the softest cases out there, and they aren't the company who's entire premise for the last 40-some years; has been soft cases for faster obturation.
Around the time of pressure testing of small primer pockets Vs large in the Creedmoor. I went down the path of testing "signs", to prove someone wrong who liked to flaunt his celebrity status online. Most cases(brand) in several different chamberings, begin to show classic "signs" of pressure when you are well north of 70,000psi, well north....
Again that's actually measured pressure, calibrated to SAAMI reference ammo. Not praying over adjusting variables in an estimation program few people even attempt to understand.

 

[Mikecr]

No, because of the calibration in a PT. You have to cast your chamber and carefully measure it out. Once those numbers go in the system, you don't get to change them like everyone does in QL. Then you order SAAMI reference ammo, carefully measure it, record and fire, then carefully section and measure the case again. Now you have a precise correction from the standards, to your chamber.

Thanks. I know bore, groove/, barrel profile/contour, alloy can be different, and that calibration is in order.
I am doing similar with QL in that I adjust bore & groove among other things.

I'm sure actual measure will always be superior to math prediction, but the overall outcome -as predicted, is fine with me.
I know some can, but I can't plan a design without prediction.