QuickLoad Question

[mr surveyor]

For RD and others that may be familiar with QuickLoad .....

Concerning barrel length of handguns .... revolvers vs pistols in particular .... is the data for barrel length based on breach face to muzzle on the "pistol" or total bullet travel distance - bullet nose (or base?) to muzzle? And for revolver, is the barrel length in the data based on forcing cone to muzzle, bullet travel distance, or recoil shield to muzzle?

Hope the questions were understandable.


jd

[GasGuzzler]

I understood so it may mean you wrote it wrong.

[mr surveyor]

now that's scary


jd

[NavyDoc76-80]

Hey JD,

You may have already gone through this exercise, but a few weeks back I was looking into QL, and discovered a few things.

1. its not a thousand dollar program like a thought, just $150
   It is only distributed through one company

And I have yet to learn the bullet function but that's for another day.

[Ranch Dog]

For RD and others that may be familiar with QuickLoad .....

Concerning barrel length of handguns .... revolvers vs pistols in particular .... is the data for barrel length based on breach face to muzzle on the "pistol" or total bullet travel distance - bullet nose (or base?) to muzzle? And for revolver, is the barrel length in the data based on forcing cone to muzzle, bullet travel distance, or recoil shield to muzzle?

Hope the questions were understandable.


jd

I understand what you are asking JD. QuickLoad is concerned with bullet travel to the muzzle so all calculations are based on the breech face, what the base of the cartridge is sitting against. Of course revolver barrel lengths are just that so consideration must be give to what QL requires. I just stick a cleaning rod through the barrel until it comes to rest and then mark and measure.

[mr surveyor]

RD

Thanks for the explanation. That effectively makes my 3" (barrel length) SP101 a 4.9" "barrel" for the QL calcs. The matter of the term "bullet travel", the way I understand it from comments made by "Iowegan" (on other forums ... I'm sure you know of him) is that it is measured from the actual base of the bullet (or is it the nose?). Thus the reason for my asking about three different possible ways to evaluate the barrel length values used by QL. Also, with the revolver, the barrel/cylinder gap is another variable to take into account. I suppose these could all be considered minor details, with the exception of the pressure curve peak in evaluating loads for a 1-7/8" snubby vs a 3" revolver (based on actual barrel length). The QL data reports I've seen for handguns (and I haven't seen very many) seem to chart results for 2", 3", 4", etc., barrel lengths. So when entering the barrel variables for a "pistol" one enters the true barrel length, which is breach face to muzzle ... then when entering barrel variables for a revolver does one enter the nominal barrel length (i.e. 3" for my particular SP101) and the full length from recoil shield/breach face to muzzle? I would also assume that b/c gap has several percentage points in play as well but is not really part of my main matter of confusion at this point. The matter of input data and output data and how they relate to a handgun spec'd as a 1-7/8 inch snubby or a 6" Black Hawk comes into play.

My Son and I are considering loading up QL in the near future and I'd like to see a tutorial on it's use. Is something like that readily available?


jd

[mr surveyor]

Actually, the length thing is soaking in to my head o.k. .... the cartridge specs entered into the variables do in fact crunch the numbers down precisely to "bullet travel" for the pressure calcs .... but is the final charted data shown as related to one's particular "spec'd" barrel length?


jd

[Ranch Dog]

I've never seen a tutorial for QuickLoad but the PDF with the software is quite detailed and is a great read.

The only thing that your length question would effect is velocity as pressure is constant no matter the barrel length. For my recorded velocities the calculations are quite a bit better if the measurement from the recoil shield/breech face is used. As a note; when I post data, like what I've done for my bullets and NOE, I use the actual barrel length on the data sheet rather than how it was calculated. It saves a lot of questions.

Here are two examples for my Rossi 351 with a 2" barrel but a measured 3.71" from the recoil shield/breech face.

The load is with my TL358-125-RF & 15.5-grains of H4227 with the temperature corrected to the actual temperature at the time of the chronograph work.

QL 2.00" Estimates:
FPS = 643
PSI = 17,435

QL 3.71" Estimates:
FPS = 974
PSI = 17,435

Actual:
FPS - 924

This load is with the same bullet but with 13.5-grains of H4227.

QL 2.00" Estimates:
FPS = 545
PSI = 12,239

QL 3.71" Estimates:
FPS = 831
PSI = 12,239

Actual:
FPS - 865

As you can see, using the longer length seems to give a better reflection of the actual velocity you will experience. I've learned this all from my experience with the product. I think you must think of a the calculations being conducted in a pressure barrel and nothing else. A pipe with a breech on one end.

[GasGuzzler]

Great examples, thanks.

[mr surveyor]

Interesting numbers RD. Your first example would fairly well correlate to the missing variable of pressure loss due to the barrel/cylinder gap, per "Iowegan's" constant of 1.5% loss per .001" b/c gap. Had you stopped right there, I would have thought I had a mental handle on it .... but NOOOOOO ... you had to throw me an anomaly with the second one

Yeah, I know there's nothing definite except death and taxes, and taxes


jd