Quickload Question

[Velocity]

I purchased Quickload a couple weeks ago and my question is about Hornady SST bullet "180 gr." and the 9th & 11th manuals.

Using the manuals for the 180 gr. SST and Accurate 1680 at 19.3 gr. I get a pressure reading of 200,696 and I can't see why, all the inputs are right, I hope.

I loaded up a ladder test of 10 rounds in February along with other loads from those manuals and with the purchase of Quickload I thought I would run them through the software as I learn it. The 10 rounds were started at 10% below the max at 19.3 gr. and at 0.2 increments the start was 17.5 gr.
The pressure for 17.5 gr. was 105,760 psi.

I have a screen shot if it's needed.

Thank you,

Vel

[dellet]

Screen shots of cartridge load data, and final pressures.

Double check case capacity and starting pressure also.

[Velocity]

I don't have an image URL. Is that the only way, the image is on my PC?

Vel

[Velocity]

I created a Dropbox link hope it works and it didn't.

ERROR Message:
It was not possible to determine the dimensions of the image. Please verify that the URL you entered is correct.

Vel

[popper]

What is seating depth? GRT shows 17 gr max with seating depth of 0.35. 90% fill.

[Velocity]

Can't post a screen shot, don't know why.

[Velocity]

Screen Shot

https://www.dropbox.com/s/2hixcg2ue43sb ... L.png?dl=0

Vel

[dellet]

Images need to be hosted on something like Photobucket or Imgur. Third party server. But the link works
Fine.

A big clue something is wrong by looking at case fill ratio. You’ll never get 140% capacity.

Then check your loaded length and seated depth.

Hornady uses 2.210”.

Still be at 115% density, but pressure drops considerably. It will still be high.

Need to compare case volume and powder lot to lot variations, but you you will at least under 100k for pressure.

I will only load 1680 to 100% max. Usually to around 105 for best accuracy.

Double check all your other numbers

[Velocity]

The Hornady 11th Edition has the 180 gr. SST C.O.L. at 2.110". Even at a 10% reduction to 17.4 gr. the Pmax is at 105,000 + and taking the COL out to 2.260" it's still 2,500 psi over.

I can get Quickload very close to other Mfg loads even the Vihtavuori loads, but the 150gr. SST - 180gr. SST and 180gr. SP have crazy PSI numbers.

Screen shot of 11th Edition page 473. https://www.dropbox.com/s/wy7ayytc4x950 ... h.png?dl=0

Also, if you change the fill rate the charge weight changes so it's not static if the other increases or decreases.

Did anyone plug in the numbers.

Vel

[dellet]

Yes, ran the numbers and they are high, but I also trust Hornady for the most part.
I have also shot thousands of 175-180 grain bullets using 1680, pretty familiar with the limits.

A case in point is the COL. The 9th edition it’s 2.210”.

I also have other manuals. Sierra shows basically the same load. Max is 19.2. Earlier Sierra data, 300 whisper, max load is 17.3 grains. That’s not uncommon either, to have data change over the years.

Accurate powder has 19.7 for a 175 SMK.

Looks like Quickload used data from a hot lot of 1680, but that’s why they give you ways to adjust the burn rate of the powders.

For what it’s worth a few years ago Hodgdon re did their Blackout data. Most everyone using Lil’gun started popping primers with the new data.

It happens and that’s exactly why the rule is to start low, work up.

Load a few at 17 grains, check velocity, check for expanded case heads. Compare that to Quickload’s and Hornady’s predictions. It takes time to learn the program and trust its outputs.

If you move the bullet out to 2.260”, make sure it’s not hitting the lands. That will certainly change your pressure.