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HALODIN wrote:It has been phenomenology accurate every time I've used mine and everyone else I've spoken to about QuickLOAD says the same. I use the MagnetoSpeed chrono.

I used an RPA interceptor in 7mm-08, Archer barrel, Remington brass, Hodgdon powders and 130, 150 and 168 SMKs for around 20 different loads. Alpha Chrony. Hodgdons own powder data was very close and Sierras was almost cock on. QuickLoads theory's weren't even close. But in back in its box and sold it.

It was fun to flick around with as a toy, but it was a "toy" non the less...

Sim G wrote:

HALODIN wrote:It has been phenomenology accurate every time I've used mine and everyone else I've spoken to about QuickLOAD says the same. I use the MagnetoSpeed chrono.

I used an RPA interceptor in 7mm-08, Archer barrel, Remington brass, Hodgdon powders and 130, 150 and 168 SMKs for around 20 different loads. Alpha Chrony. Hodgdons own powder data was very close and Sierras was almost cock on. QuickLoads theory's weren't even close. But in back in its box and sold it.

It was fun to flick around with as a toy, but it was a "toy" non the less...

I've never used QuickLoad myself, but hear me out. Did you make the most of all the input criteria available? Part of my day job is to model data for engineering processes and one thing I can say for sure is that your model accuracy improves with additional factors that maximise the response. In order for QuickLoad to be sold they would have had to carefully model all of the input parameters that are available and demonstrate a good level of fit to produce good pressure and velocity calculations. With this in mind if QuickLoad offers you 10 inputs for example, and you only input data for 4 inputs of those inputs then the unchanged values for the other 6 inputs will cause your model to produce a result with a large amount of error. As Adam mentioned, garbage in garbage out etc.

Back to my OP, this is the most amount of data I can provide (save for H20 capacity and case length) to produce a result, therefore I would expect a level of error in the calculation.

It's not just a question of inputting all the data you have.

The data already in QL is the best they can get hold of but can never be definitive.

Powder burn rate will change from batch to batch. Bullet weight can vary quite a lot within just one box of bullets. Bullet shape can vary as the dies wear during manufacture. Case capacity will vary from batch to batch. Primers make a difference. Your chrono is unlikely to be spot on.

If you change the value of just one of these variables in QL it won't make a lot of difference, but several small variations can add up to a significant error.

Once you have a baseline measurement using your hardware, you then 'calibrate' QL by making small changes in the bullet weight, case capacity, burn rate etc. and those changes compensate to give you accurate results. You're not necessarily entering the actual values for those data. You're just using those variables to offset other errors you can't measure.

It works and if you tweak the correct values within a limited range you will find the results are very accurate.

As Dromia says though, work up an initial load in small increments using observation in order to establish the pressure limit. QL's pressures are purposely over-optimistic to avoid people jumping straight in with a load they've calculated with the software only, but you should never use ONLY QL to determine a load, especially if it's likely to be pushing the gun's limits in any way.

Your experience is the polar opposite of mine. I would even say it was spot on, I was surprised how accurate it was. As others have said, I only use QL to verify my chrono. When I get a match I know the data is sound.

Sim G wrote:I used an RPA interceptor in 7mm-08, Archer barrel, Remington brass, Hodgdon powders and 130, 150 and 168 SMKs for around 20 different loads. Alpha Chrony. Hodgdons own powder data was very close and Sierras was almost cock on. QuickLoads theory's weren't even close. But in back in its box and sold it.

It was fun to flick around with as a toy, but it was a "toy" non the less...

If you feel it works for you, then all power to you. Me, I have absolutely no confidence in the program outside of "entertainment".