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Discussion Starter · #1 ·
Been using the program for a few years and I'm becoming less and less happy with its predictions as I become more experienced. I started out using it for my Tac 20 and ended up 2 full grains higher than what it suggested was max with zero signs of pressure. No books I could find to back that up other than Todd Kindlers.

Next I've been working on my 6.8 SBR but here I've found written major differences. With Accurate 2200, coal 2.295, 95 TTSX plus I measured H20 capacity, case length and bullet length and made those corrections. Anyway it shows my max pressure is obtained at 28.5g where as The Accurate powder manual shows max at 30.2 with a coal of 2.26O with 57600 psi. This same load in QL shows a pressure of 71000 psi.

Is is there a way of tweaking this program? To show more accurate data? Really frustrating. Also I've read your realoding forum top to bottom which is part of what made me question all this. Great resource by the way.
 

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Changing the bore area and engraving force will help if you are using anything other than a 6 groove barrel with a 50:50 L-G ratio. Are you using the case capacity of a fired case?
 

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Discussion Starter · #3 ·
Changing the bore area and engraving force will help if you are using anything other than a 6 groove barrel with a 50:50 L-G ratio. Are you using the case capacity of a fired case?
Not sure I totally understand your post. How and where do I find the bore area and engraving force so I can change it and what do I change it too? I'm using an 11 twist Shillen barrel, not sure on the groves. I'm not using the case capacity of a fired case. I purchased 1000 new S&B primed cases so I'm using new case capacity till I shoot thru the 1000.
 

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Not sure I totally understand your post. How and where do I find the bore area and engraving force so I can change it and what do I change it too? I'm using an 11 twist Shillen barrel, not sure on the groves. I'm not using the case capacity of a fired case. I purchased 1000 new S&B primed cases so I'm using new case capacity till I shoot thru the 1000.
You will have to calculate the bore area based on the design of your barrel, engraving force also. The default engraving force is figured based on a 50:50 land-groove ratio, you need to change it to match your barrel. You should use the fired case capacity not new case capacity.
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Discussion Starter · #5 ·
I'm curious as to why I should use a fired round for case capacity when I'm using new brass? Shouldn't the case capacity be exactly for the unfired case I'm currently loading for? Please enlighten me
 

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I'm curious as to why I should use a fired round for case capacity when I'm using new brass? Shouldn't the case capacity be exactly for the unfired case I'm currently loading for? Please enlighten me
Your chamber size is what matters. When you touch off a round the brass expands to the chamber size. What your brass was to begin with is irrelevant.
 

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Discussion Starter · #7 ·
Ok, that makes sense, thank you

since I don't yet fully understand the terms you threw at me earlier in the discussion I will research more on my own till I have intelligent questions on that pressure subject.

Next, concerning velocity differences my Magnetospeed is 220 fps lower than what the program is suggesting. I thought I read somewhere that I can adjust these velocity readings to match what velocity I'm actually getting. Is that possible and how do I do it? Thanks again for taking the time to help.
 

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Ok, that makes sense, thank you

since I don't yet fully understand the terms you threw at me earlier in the discussion I will research more on my own till I have intelligent questions on that pressure subject.

Next, concerning velocity differences my Magnetospeed is 220 fps lower than what the program is suggesting. I thought I read somewhere that I can adjust these velocity readings to match what velocity I'm actually getting. Is that possible and how do I do it? Thanks again for taking the time to help.
You can adjust the burn rate of your powder. Sometimes this will make the fps coincide a bit better...

I have found QL to be a bit optimistic with velocities and a bit conservative with pressures. At least for many of the cases I have used...

I use it as a guide and if it shows high pressures with a certain load, I start looking a bit closer at the cases and how the velocity is increasing as a add another .5 grain of powder...

I do like the feature where it will attempt to find a powder and charge to match the parameters you wish to duplicate from other loads...

A tool and I think a good tool for the serious reloader...

Some on this site will disagree for sure...

Good-luck...BCB
 

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Discussion Starter · #9 ·
Unfortunately it seems the inventor of this product has stopped developing it completely sans updating powders and bullets. It has so much potential. You could add Primers, barrel twists, adjust the program to match already documented pressures, and so on. It's ashamed! About all I trust it for now is matching powders to bullets and these days all one must do is cruise different Forums to get a decent idea of what powders work.
 

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About the only thing quickload is good for without SERIOUS tweaking is telling you which powders will give you the best velocity given your input parameters. I would NEVER rely on quickload for actual load data.
 
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