Would like QL help

1340

1340

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I have been playing with QL, trying to find another good powder for my 20BR. I looked at all the info; velocity, pressure, OBT, fill % and burn%. I'm leaning towards Hodgdon Leverevolution. I want to stick to Hodgdon powders. Specs are; Lapua cases - 37.82gr water, 40gr bullet (Hornady Vmax/Berger Varmint). OAL 2.064", trim length 1.510". I usually use a temperature of 86°Fahrenheit. Am I on the right track? Advice appreciated.
 
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depending on distance off lands, you'll find QL predictions will match up closer to reality if you adjust the Shot Start (Initiation) Pressure up from the default of 3626psi to something around 8000 up to 10000 if you're closer to the lands

This will decrease the charge weight to hit ____ PSI chamber pressure
 
jamesharrison said:
Here's the #'s for Hodgdon powders. Note, I estimated a 24" barrel. QL defaults to 85% of PMAX for powders. You want to go above that, it's your face behind
jamesharrison said:
Here's the #'s for Hodgdon powders. Note, I estimated a 24" barrel. QL defaults to 85% of PMAX for powders. You want to go above that, it's your face behind the bolt.

View attachment 910799
Click to expand...
jamesharrison said:
Here's the #'s for Hodgdon powders. Note, I estimated a 24" barrel. QL defaults to 85% of PMAX for powders. You want to go above that, it's your face behind the bolt.

View attachment 910799
Click to expand...

the bolt.

View attachment 910799
Click to expand...

todbartell said:
depending on distance off lands, you'll find QL predictions will match up closer to reality if you adjust the Shot Start (Initiation) Pressure up from the default of 3626psi to something around 8000 up to 10000 if you're closer to the lands

This will decrease the charge weight to hit ____ PSI chamber pressure
Click to expand...
Thank you for the replies.
todbartel; I'll try that tip. There is a way to calculate that value.
Jamesharrison; your second image is kind of what I'm not able to figure out how to do. I just wanted to know if my pick of Hodgdon LVR was a good choice. All the specs except burn% are good. My barrel is 24", but my weight of water is 37.82gr. and I'm presently .005" from jam.
todbartell said:
depending on distance off lands, you'll find QL predictions will match up closer to reality if you adjust the Shot Start (Initiation) Pressure up from the default of 3626psi to something around 8000 up to 10000 if you're closer to the lands

This will decrease the charge weight to hit ____ PSI chamber
Click to expand...
 
In QL, go to OPTIONS, then go to Setup Propellant Table, expand it, then copy to EXCEL & voila. Since you said you wanted to stick to Hodgdon powders, I deleted all the rest as well as the Hodgdon powders that did not fill the case to at least 85%.

I did input 37.82 grs of water as the screenshot shows under "Maximum Case Capacity Overflow.

As Todd pointed out, the shot start pressure, if you're only 5 thou off the lands will be higher than the default 3,626 psi. I also did not include the calculation for land & groove measurements.

Typically when working up a load, I will start with QL, then cross-check it with GRT, just to give me an extra measure of confidence.
 
jamesharrison said:
In QL, go to OPTIONS, then go to Setup Propellant Table, expand it, then copy to EXCEL & voila. Since you said you wanted to stick to Hodgdon powders, I deleted all the rest as well as the Hodgdon powders that did not fill the case to at least 85%.

I did input 37.82 grs of water as the screenshot shows under "Maximum Case Capacity Overflow.

As Todd pointed out, the shot start pressure, if you're only 5 thou off the lands will be higher than the default 3,626 psi. I also did not include the calculation for land & groove measurements.

Typically when working up a load, I will start with QL, then cross-check it with GRT, just to give me an extra measure of confidence.
Click to expand...
It looks like I have more learning to do. I do have GRT, but haven't been able to figure it out at all.
The 85% comes in on the second attachment?
 
Eventually; you first have to specify your propellant data parameters, like the first photo,

propellant table set up.jpg

then hit apply & you get the 2nd photo.


table.jpg

Then you copy to EXCEL & delete the powders you don't have or want to see.
Also, forgot to mention, but with your chosen C.O.A.L. & bullets, you've only got 0.085" bullet seating depth [the tapered boat-tail doesn't count as it is NOT touching the case]!
 
I don't want to hijack this thread, but have wondered about how to create a file from QL output for posting on the forum. I create the output I want, but just copying this as a file results in the results being somewhat distorted--out of proper alignment. How can I create an exact copy of the output from QL?
 
It used to work on CGN nicely when you used the feature. Since the update on CGN it doesn't display it very nice
 
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