Yes, I know there is no replacement for reloading and shooting to find your best safe/accurate load. However I read so much about Quickload that I thought I would try it just to play "what if" scenarios when it is too cold and wet to go out and shoot. (Is there such a thing as too cold and wet for shooting??). Anyway, tried to run it using the recommended values from the Hodgdon load data for the 338 Lapua, 300SMK, H1000 and find velocity and pressure values to be so far different that I wonder what value there is to Quickload. Depending on powder weight Quickload is telling me the pressures are anywhere from 10,000 to 20,000CUP greater than what the Hodgdon website indicates, and I see many people using those same powder charges with no apparent problems. For example Hodgon for 92 grains of H1000 gives fps at 2590 at 53,000 while quickload gives 2710 fps at 64,000. I know there will be some differences as QuickLOAD is just a math model, but 110 fps and 11,000CUP??
I trust QL, where I input my exact case capacity, exact OAL, exact barrel length, exact bullet, and exact powder charge, a WHOLE lot more than I trust any printed loading manual.
I still have a bunch of loading manuals but they rarely get touched since I got QL.
QL is easy enough to learn once you start taking all the factors into account -that reloading manuals never could.
You can validate/feedback things like your formed case capacity, bullet shank seated into neck, muzzle velocity, bore area, etc to calibrate. THEN you can run what-ifs.
You can also compare your QL predictions to loads listed at ReloadersNest.com and tweak inputs to lock into match.
I shoot HBN coated bullets. I own several "wildcats" that require my own reamers and even gauges. I like to achieve the highest possible velocities. Quickload is used to choose powders to investigate with the bullets I want to shoot. I find that the people putting together the reloading manuals often have an interest in pleasing lawyers rather than experimenters. Look at the Alliant data for .264 Win Mag. I got more velocity with WWII surplus H4831 when I started handloading then they do with "maximum" loads with R-22 and R-25. Nosler factory data is another mystery to me. These folks must be allergic to velocity.
I have used it with some good success, but more recently I have had better success, at least with the conventional calibers actually using this site by posting inquiries, or searching for a particular cartridge, many times even narrowing down to components I have on hand, or even a particular rifle. This has over the past couple of years proven to be the fastest way for me to get to an optimal load. I know all rifes /barrels can have different characteristics, but I have been quite surprised by the similarity of loads and results obtained by multiple shooters for a given cartridge. This approach has put me in the ball park, leaving just fine tuning, on several occasions.
"Let us speak courteously, deal fairly, and keep ourselves armed and ready"-T. Roosevelt
65WSM has the right idea: QuickLOAD is useful for finding powders with good loading densities. But then, so is a spreadsheet with a list of bullet lengths, cartridge dimensions, and powder densities.
However, I no longer believe it can be used as an internal ballistics model. The further you go from old-school loads the worse it gets. Efficient subsonics like 300 BLK are off by 200fps. Heavy bullets in higher-twist barrels are also off by at least 200fps. Newer powders show greater variances than older powders.
The reason was explained to me by an exceptionally experienced tech at Hodgdon: The internal ballistics models require parameters that no powder manufacturer tests or provides. The only reason QuickLOAD got off the ground is that in the 1990s Hartmut Bromels got his hands on a bunch of such data the KGB had accumulated (at considerable cost). He has essentially been trying to data-fit new powders ever since, but the characteristics of smokeless powder have evolved too much for this to work outside of a narrow band.
Note that these errors invalidate QuickLOAD not only for out-of-manual load development but also for one of its other popular purposes: which is to find Optimal Barrel Times (OBT).