Serious error in Quick Load?

I just measured a cleaned resized case trimmed to 2.620" with a new Winchester large rifle magnum primer full of distilled water - it held 91.3 grains of H20.

By the way, you are assuming I was concerned more with what my actual load produced in my rifle. I was far more concerned with the difference of the projected load by QL and the Hornady load data.
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So, the reason behind measuring the FIRED brass capacity is that is what is important in YOUR rifle. You are never going to be able to replicate the Hornady loads from the manual 100% UNLESS you have the exact same lot of brass, powder, primers, bullets, and importantly the same gun that Hornady used to work up the data. And by that I mean literally THE gun Hornady used.

Why? Your logic that the same pressure will result from two different chambers is the thing. I have one rifle that has a tight chamber and the body of it's brass hardly grows at all when I shoot it. Then I have another rifle that the case volume is increased by 6 full grains of powder from a "cleaned resized case"

If you factor powder lot variations etc you can see why they do not match up exactly.

So if you have a large chamber in YOUR rifle that results in a 5 or 6 grain increase when fired, your pressure will be less than if the chamber were holding the brass to 91.3 grains.
 
HoustonBob said:
I just measured a cleaned resized case trimmed to 2.620" with a new Winchester large rifle magnum primer full of distilled water - it held 91.3 grains of H20.
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Hornady: 25" barrel Hornady brass Winchester WLRM primer 110 VMAX 69.0 grains of Varget COL 3.300" 3700 fps. Max Load for Hornady.
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Curious as to why you use the resized case volume while the QL manual says to use fired case volume, not resized, for cartridges with peak pressures over 30,000 psi.
 
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Why? Your logic that the same pressure will result from two different chambers is the thing. I have one rifle that has a tight chamber and the body of it's brass hardly grows at all when I shoot it. Then I have another rifle that the case volume is increased by 6 full grains of powder from a "cleaned resized case"
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Dessiminator's point here is amplified in the .300wm. The .300wm is unique in how much a factory, unfired, case grows in the first firing. Using my case gauge, I measure Norma Brass from casehead to datum to be 2.55". Upon firing, that same measurement is 2.700-2.7005". So almost 0.15" growth, and that's in my tight chambered competition gun. In some rifles with different brands of brass, when headspaced off the belt as factory new, the may grow up to 0.20" from casehead to Datum....Most other cartridges do not grow nearly that much, and Also, for that reason, it is critical to headspace a .300wm load off the shoulder or else you risk casehead separation after just 1 load. the difference between a "go" gauge and field gauge in the .300wm is 0.007".

Also, my competition load pushes as 225 gr bullet 2905 fps at approximately 59k psi in my .300wm. If I were to use Remington brass, I would be over 75k psi and over 3100 fps.

Also, as I mentioned above, testing over a chronograph would be useful in determining who is closer to your velocities. However I am betting it is Quickload. I have hornady manuals, Lyman, Sierra, nosler, Speer, Barnes, and use Hodgdon's website. I have found Lyman to be the closest to what I am able to achieve, but not as close as Quickload who is usually within 1% or less.
 
Also, as I mentioned above, testing over a chronograph would be useful in determining who is closer to your velocities. However I am betting it is Quickload. I have hornady manuals, Lyman, Sierra, nosler, Speer, Barnes, and use Hodgdon's website. I have found Lyman to be the closest to what I am able to achieve, but not as close as Quickload who is usually within 1% or less.
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I have chronographed my loads with heavy bullets on my Remington 700 Long Range (26" Barrel) they are very close to both Quickload and the Hornady manual - both of which pretty much agree. What started this whole thread was when I used a Chronograph on my load with 110 grain bullets (I was looking for an accuracy node that my alpha level resonance software predicted would exist) and the chronographed results were in line with the Hornady manual (25" barrel) and not close to the Quickload data. That is why I think Hornady is correct and Quickload is throwing spurious results with 110 grain bullets.

It is difficult for me to see why heavy bullets give chronograph readings in line with both Hornady and Quickload, then give readings in line with Hornady with 110 grain bullets - but not in line with Quickload - and somehow the problem lies with my rifle and Hornady, and not with Quickload.
 
So, the reason behind measuring the FIRED brass capacity is that is what is important in YOUR rifle. You are never going to be able to replicate the Hornady loads from the manual 100% UNLESS you have the exact same lot of brass, powder, primers, bullets, and importantly the same gun that Hornady used to work up the data. And by that I mean literally THE gun Hornady used.
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No, the reason I measured the case volume is because you accused me of not answering your question. So I answered your question - that is all. I delayed answering it because I was out of distilled water, I picked some up on my weekly run to the grocery store.



Curious as to why you use the resized case volume while the QL manual says to use fired case volume, not resized, for cartridges with peak pressures over 30,000 psi.
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I was answering a question.
 
Curious as to why you use the resized case volume while the QL manual says to use fired case volume, not resized, for cartridges with peak pressures over 30,000 psi.
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I got 92.9 grains of H20 for the piece of cleaned but not resized brass who's volume I just measured.
 
I have chronographed my loads with heavy bullets on my Remington 700 Long Range (26" Barrel) they are very close to both Quickload and the Hornady manual - both of which pretty much agree. What started this whole thread was when I used a Chronograph on my load with 110 grain bullets (I was looking for an accuracy node that my alpha level resonance software predicted would exist) and the chronographed results were in line with the Hornady manual (25" barrel) and not close to the Quickload data. That is why I think Hornady is correct and Quickload is throwing spurious results with 110 grain bullets.

It is difficult for me to see why heavy bullets give chronograph readings in line with both Hornady and Quickload, then give readings in line with Hornady with 110 grain bullets - but not in line with Quickload - and somehow the problem lies with my rifle and Hornady, and not with Quickload.
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Interesting. Have you measured the actual 110 gr bullet you are using? and then looked at quickloads measurements? Maybe you already know this, but once you select the bullet in quickload, it can be edited by selecting the bullet dropdown menu. Perhaps quickload has the incorrect bullet dimensions.

Also, make sure to use the 0.39 weighting factor for the .300wm. It matters more at higher velocities.

If the bullet dimensions are correct, then perhaps you could call NECO and see what they say. Also, try and look at other manuals who have similar bullets/powder and see what velocity they get? Perhaps Hodgdon? Hodgdon says 3,660 with 72.5 gr Varget in a 24" barrel. 67 gr Varget in a 24" barrel is 3424. In otherwords, Hodgdon and QL are close to what you are seeing, and they made the powder..But Hornady made the bullet.
Hodgdon is using WLR primers, Win case, 24" barrel.

Im sure Hornady used their own brass.

I guess I would measure the bullets next if you have not already
 
Mississippi said:
Dessiminator's point here is amplified in the .300wm. The .300wm is unique in how much a factory, unfired, case grows in the first firing. Using my case gauge, I measure Norma Brass from casehead to datum to be 2.55". Upon firing, that same measurement is 2.700-2.7005". So almost 0.15" growth, and that's in my tight chambered competition gun. In some rifles with different brands of brass, when headspaced off the belt as factory new, the may grow up to 0.20" from casehead to Datum....
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I don't see how it is possible the brass "grows" over the rifle's headspace.

-TL
 
don't see how it is possible the brass "grows" over the rifle's headspace.
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It doesn't....the .300wm is a belted magnum. If you want more info on belted magnums like the history of why the belt is there, just look up the .375 HH and the .300HH. The belt exists because there isn't enough shoulder to headspace the cartrige without the potential for the firing pin to push the cartridge too far forward.

Anyway, the .300wm, has enough shoulder to headspace off of, but it still has a belt since the parent case was a .375 HH magnum that the .300 wm was developed from. So, initially, the .300 wm headspaces off the belt, but there is a generous gap in most chambers between the shoulder and chamber such that the cartridge grows by as much as 0.020. You "could" theoretically size it back down that much, and continue to headspace off the belt, but it will grow again by that much to fit the chamber. So, instead, after the first firing, you push the shoulder back 0.002 and from then on you are headspacing off the shoulder.

If you headspace off the belt on subsequent firings, it is likely in a .300wm you will experience casehead separation because that means you are pushing the shoulder back relatively far, and so the case has to stretch a lot on subsequent firings. However, if you headspace of the shoulder after the first firing, then the cartridge is sized and headspaced like most other bottleneck cartridges and will generally last for numerous reloading with primerpockets being the "worn out" indicator rather than the pressure ring above the web.
 
I see. So when measuring the fired case, the brass is no longer resting on the belt datum, but the elongated shoulder. That makes sense.

There is another possibility, I think. The fired case may have diameter bigger than the ID of the gauge, so it is not even resting on its shoulder.

Thanks.

-TL
 
HoustonBob,

A misconception:

There is no SAAMI standard case capacity. SAAMI only gives numbers for the outside dimensions of cases. There are several reasons for this, but the bottom line is that it is up to a case maker to ensure enough strength by testing. The @ case in QuickLOAD is just an average of the other numbers noted for cases. The reason for the brand-specific cases listed as if they were separate cartridges is the 300 WM has more case capacity variation from brand-to-brand than any other popular cartridge out there. This is why you have to get specific about capacity.

Varget has a particular problem in that its burn rate changed some since its introduction. Hodgdon tightened their burn rate QC after around 2000 and after getting complaints about Varget lot variation. I don't know what portion of the QuickLOAD powder data came from older lots, so it's one to watch out for a bit more than you might some others when comparing QL data to other data.

The Hodgdon data doesn't use a Hornady case, it uses Winchester, which has more space in it. Hodgdon names the case at the top of its data. If you use a different 300 WM case, except for Norma, the Hodgdon data will be too high. This is why we use the recommended low load limit as the starting point and work up. That quickly tells you if you have unreasonable velocities and that something is amiss.

The QL instructions state specifically to use as-fired case volume for cartridges peaking at pressures over 30,000 psi, and as-resized for cartridges peaking below that number. It is roughly the threshold at which case growth begins to occur. (.45 Auto brass, for example, running at around 20,000 psi most of the time, actually shortens slightly with each load cycle.)

Bullets have changed a lot over the last quarter century. M.L. McPherson and a collaborator did some experiments with a 270 Winchester pressure test gun in which he fired about every 130 grain bullet made over the same load with the same cases, and got, IIRC about 30% peak pressure variation. Bullet weight alone is not enough to determine load safety at this point. The bullet in Hodgdon's data is made by Speer.

QuickLOAD has no direct mechanism to allow for bullet jump to the throat of a rifle. You have to adjust start pressure to compensate. This applies to bullet hardness as well. If you have a bullet in or very close to contact with the throat it can raise peak pressure about 20% with standard cup and core bullets, though it seems unlikely a 110 grain bullet would reach that far.
 
Quick load is a computer program. It takes the data you give it and calculates information that meets the input. The software can't tell if you are putting in the correct information. As the saying goes, "garbage in, garbage out". If you don't give the software precise information in your load then it will give answers that are meaningless to you.

It is not a software error - it is an input error.
 
Unclenick - good information thank you for posting that.

Since the 110 grain bullets are seated below the 3.340" nominal case length (3.300 +/- .002" as built) it is also a bit difficult for me to see how a rifling jam could be raising the pressure...

Unless those bullets have such a long jump to the rifling from the case that they are entering the rifling seriously out of alignment, and that is causing higher than expected pressures to get them started. Now that makes sense, and could explain both Hornady's data and what I saw with my rifle. A short bullet could get twisted much more easily than a long one.
 
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I also doubt it's the issue. Just in case, though, keep in mind that jump is determined by where the bullet ogive contacts the lands, not the tip, so COL alone doesn't really tell you anything about it unless you are talking about bullets with the same nose profile. If you have, for example, a bullet that is a stubby shape with the ogive coming off the bearing surface (the cylindrical portion) far enough forward, you can still make contact even with a short COL. The illustration below shows two bullets with the same jump, but very different COL because of their profile differences.

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Because the rifling on my 300 Win Mag doesn't start until the ogives are out of the case mouth by .250" (out of a standard 2.620" long case's mouth) almost the entire bearing surface of the 110 grain bullets is out of the case before the bullet touches the lands. I don't believe that the distance they travel in my rifle is at all unusual for a .300 Win Mag.

I have a dummy cartridge that has a long bullet extended until it just touches the lands and less than .020" of the bearing surface of that short 110 gr bullet would still be in the cartridge mouth if I place the ogive of that long bullet in the dummy case next to the ogive of the 110 gr bullet.

The 110 grain bullet can be seriously out of line before it touches the rifling.
 
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