Quickload thread

[ascast]

you have to be new to ask stupid questions ? so I can ask no more?

[marten]

The manual just about explains barrel time as good as can be explained but let us break it down a little.

Although I have a fair knowledge of External ballistics, my knowledge of Internal ballistics needs more study. For what it is worth, this is my understanding of the barrel time feature.

We can use the calculations for a 20 inch 30-30 barrel, firing a 170 grain Ranch Dog bullet ahead of 25.3 grains of IMR 4895.

The bullet exits the muzzle with a velocity of 1,602 feet per second and the maximum pressure of the burning powder in the barrel reaches 16,282 pounds per square inch.





Time is measured in milliseconds or one seecond divided by one million ( 1 / 1,000,00 )
The barrel time chart shows that the maximum pressure is reached in approximately 6.6 milliseconds.



Now, if you closely examine the barrel time chart, you will notice that the pressure trace line does not start at zero. The trace line starts when 10% of the MAXIMUM PRESSURE is reached (Approximately 162 psi) and ends when the bullet exits the muzzle.

The Barrel Time or the elapsed time from the 10% max pressure point to the muzzle is 1.86 milliseconds.




As I mentioned before, I am no expert on internal ballistics calculations or measurements, I can only assume that the very begining of the combustion process is difficult to measure or calculate so an arbitrary 10% of max pressure is used as a comparison point for all measurements and calculations.

So, for whatever reasons, all of QuickLoads Barrel time measurents start at 10% of the maximum pressure.

One of the reasons that it is desirable to be able to calculate the bullet barrel time is that the speed of sound or the shock wave in a barrel is constant. The barrel vibration at the muzzle has a direct effect on the direction of travel imparted to the bullet as it leaves the muzzle which in turn determines accuracy and group size. If good grouping is attained at a certian barrel time dwell then one might assume that another load that produces the same barrel time dwell might also produce good groups.

There are more considerations concerning the time in milleseconds between the extremes of the muzzle deflection time and direction as related to barrel length that may be measured and calculated.

Hope this helps.

1 millisecond is 1 second divided by 1000 not 1000000

[Tom Myers]

1 millisecond is 1 second divided by 1000 not 1000000

Yikes!!!

Marten,
Thanks for catching my error. It appears that I am a victim of phonetic suggestion. I know that, actually, "milli" denotes one thousand but, when my attention wanders, one million seems to pop up.

I will edit the post to read correctly.

[wordsmith]

Since I'm new here, I'll ask the stupid question. It seems like a lot of people rely on the chrono results but my main concern is pressure not velocity. The reason I bought QL was to model the peak pressure-vs- curve shape of different powders. QL tells me that all else being equal (case, bullet, OAL, etc) different powders will produce the same velocity with significantly different pressures. My thought is that the powder that produces the desired velocity with the lowest pressure is the safest and easiest on equipment. What confuses me is that I seem to be the only one on this tack....am I missing something?

Camobob - I think you're close, but my opinion is that it's more of an "optimum" pressure versus a lowest pressure. Based on my experience, a calibrated load (meaning real chrono data to dial in the QL burn rate) providing a 96-98% "Amount of Propellent Burnt" is the most efficient way to produce the desired velocity, and will produce best accuracy.

Higher percentages of "Propellent Burnt" indicate too fast a powder and can give you dangerously high pressures to get the top velocity. Lower percentages may or may not get to the desired velocity because the powder is too slow, and while the pressures will likely be lower, so too will the efficiency, accuracy, and cleanliness of the burn ("dirty ammo syndrome").

[VintageRifle]

Not sure what is included. But there is an data update available now.

QuickLOAD/QuickTARGET DATA UPDATE for V3.0 ,3.1, 3.2, 3.3, 3.4, 3.5, 3.6 and 3.8

This is a data update disk. It will add the latest available data to your current version of QuickLOAD if you have V3.0 - V3.6 and V3.8.. The data contained is current as of SEP 2015

[264 Win Mag]

That's what we have been waiting for. Now let the speculation begin regarding which new powders were included!

Thomas

[BCB]

http://www.neconos.com/item/QuickLOA...5-36-and-38-96

Wish it said what was updated--Or maybe I missed that part...

Guess I will order the update...

Thanks...BCB

[VintageRifle]

Thought I read someplace it was updated 9/19/2015. However, I cannot find that information now. Did sent and email to the company asking if any new powders have been added.

Update: got a response as to what powders have been added.

Reloader 23 and 26

[dragon813gt]

So pretty much none of the new powders. There are a lot of them so the update is pretty disappointing.

[BCB]

Thought I read someplace it was updated 9/19/2015. However, I cannot find that information now. Did sent and email to the company asking if any new powders have been added.

Update: got a response as to what powders have been added.

Reloader 23 and 26

Yea, if that is all there is to it, the price plus shipping is terrible...

Hell, the shipping is 2/3 of the cost of the update...

Hopefully there will be more to it...

Good-luck...BCB

[VintageRifle]

There is probably more to the update. I just asked about powders.

[BCB]

There is probably more to the update. I just asked about powders.

Actually, the powder was the thing I hoped to be updated--say, another bunches of powders added!

Oh well, we shall see what we shall see...

Good-luck...BCB

[BCB]

Just got the CD update...

It won't download!!!...

Anyone else have this problem?

Pretty disappointed...

Thanks...BCB

[BCB]

Never mind the above post!!!...

I got it to install, but it did not automatically start...

I had to go into the files on it and view some and finally I guess I clicked on the correct thing and it went through the usual installation rituals...

But, it's installed...

There are a couple more Reloder powders listed, at least different ones than the Manual indicates are available. It is difficult to tell as there is no way one could remember what was there before the update...

I sure wish the manufacturer would reveal what was actually updated. If it was just the couple of Reloder powders, the update isn't worth it at all...

Good-luck...BCB

[264 Win Mag]

BCB,
Could you check and see if any of the new fangled IMR powders are in there? Really interested in 4451.

Thomas

[dragon813gt]

Any new Accurate powders like LT-30 and LT-32

[BCB]

Nope to the IMR and Accurate powders...

[264 Win Mag]

Bummer. I would say maybe next year but this update was almost 18 months since the prior one.

Thomas

[dragon813gt]

There are a lot of new powders out and they need to add them to keep the program useful. The shortage has led to a lot people w/ new powders that need to be worked up and there is little data available for them.

I was really hoping LT-32 was added because I bought a good bit of it.

[264 Win Mag]

My issue is using the new powders with uncommon cartridges. I recently purchased a rifle chambered in 300 Savage. Guess how many of the manufacturers are working up data for that cartridge.

Thomas