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I've been using Quickload for a short time now. Can someone explain to me why Quickload predicts velocity to go down as the bullet is seated longer (less jump/closer to lands) but when shooting over the chronograph, the velocities are often increasing as the bullet is seated closer to the lands?
I assume the pressure is increasing when the bullet is closer to the lands, but Quickload is not predicting the velocity correctly the way I have input the data.
Are there some settings I should be looking at for Quickload to be giving more accurate results? Thanks.
Last edited by SD300; 07/24/17.
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Campfire Regular
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QL has no variable or parameter to address distance to lands, or where the lands are in an individual rifle. One might, purely for the purposes of thinking about it and getting started, consider QL to 'assume' a fixed D-T-L. Thus, changes you make with seating depth would, for the purposes of QL's calculations, simultaneously 'move' the lands as well. Clearly this is not what happens in an actual rifle, but it helps explain why QL's predictions work the way they do.
Have you read the QL manual? It's extremely helpful.
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Joined: Jan 2002
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Yeah I read it but it's been a couple of months. I probably shpuld read it again now that ive been using it more. I thought I remembered reading about a variable to change if you were loading into the lands (which I'm not) but I thought maybe there was some other input to address when the bullet is approaching the lands.
It makes sense that seating the bullet long in the case would create less pressure with the same powder charge in a deeper seated bullet but my chronograph is telling me the opposite from what quickload is showing since I'm seeing more velocity as the seating depth decreases.
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The variable you're thinking of is Shot Start Pressure. While one can use that to attempt to address distance-to-lands changes, I have not found it to be adequate to adjust for relatively longer D-T-Ls. According to controlled pressure testing published by Dr. Lloyd Brownell (University of Michigan) in the '60s, max pressure in bottleneck centerfire rifle cases (he used the 30-06) will be seen when you seat the bullet ogive at the lands or slightly jammed. Pressure decreases as seating depth increases the distance to the lands. At some point pressure bottoms out and starts to climb again, but never reaches as high as the jammed pressures.
He offered the hypothesis of gas leakage around the bullet to explain why pressure decreases as bullet 'jump' increases. I suppose one might be able to mitigate this, if it is the correct explanation, by reaming a super-tight leade diameter or something like that. I'm not sure because I haven't tried it. I have replicated his overall findings of where peak pressure is, though, using my Pressure Trace.
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Campfire Outfitter
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Based on casual observation of velocity, my best guess is that pressure decreases as you seat longer until you come within about 0.012" to 0.015" from the lands, then pressure begins to rise as you get closer to the lands from that point. This is just what I've seen when looking at chronograph results during the seating depth stage of load development, and with a limited number of cartridges.
Don't be the darkness.
America will perish while those who should be standing guard are satisfying their lusts.
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Bottom of the pressure curve is best expressed in terms of number (fractions are numbers) of calibers from the lands.
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Campfire Greenhorn
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the further out a bullet is seated, the more available volume inside the case. The more available volume, the lower the pressure. The lower the pressure, the lower the velocity. The only to make this up is to increase the powder charge.
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There's more in play than just cartridge case volume, and the other factors have a larger impact, so it ends up not working that way for normal rifles and bullet seating depths.
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the further out a bullet is seated, the more available volume inside the case. The more available volume, the lower the pressure. The lower the pressure, the lower the velocity. The only to make this up is to increase the powder charge. In a rifle where a bullet can be seated out far enough to contact the lands, this is not true. There are TWO ways seating depth affects pressure, not just one.
Don't be the darkness.
America will perish while those who should be standing guard are satisfying their lusts.
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Campfire Greenhorn
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Campfire Greenhorn
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the further out a bullet is seated, the more available volume inside the case. The more available volume, the lower the pressure. The lower the pressure, the lower the velocity. The only to make this up is to increase the powder charge. In a rifle where a bullet can be seated out far enough to contact the lands, this is not true. There are TWO ways seating depth affects pressure, not just one. Very true and an important point to remember
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Folks ,
Does QucikLoad have loading data and allow you to input a caliber -bullet -primer and powder then give you recipe ?
If not , exactly what does it do to help the average loader ??
I AM NOT KNOCKING THIS PROGRAM , I just don't understand what it does or if I should purchase it ?
Thank you in advance for your time and consideration.
Soup
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User inputs are normally the bullet, powder, cartridge OAL, and barrel length. You can also tweak case capacity and a burn rate factor called "Ba" in the program. If you like you can also alter "start pressure" in order to simulate seatinf very close to the lands and you can also set ambient temperature. There is no input for brand of brass or primer.
Don't be the darkness.
America will perish while those who should be standing guard are satisfying their lusts.
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Joined: Aug 2014
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RiverRider ,
Thank you for your prompt reply .
After you input the information you noted above does it give you a recipe similar to a reloading manual ?
Thank you
Soup
Last edited by Soup; 09/17/18.
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Not really. I can run a cartridge to see how different powders will behave or I can run a certain single powder to let QL predict results. Here are examples. In this instance I've run a powder profile to see what powder would work best in a .270 with a 130 Partition. My barrel length was set up at 20 inches, which is ridiculous IMO, but I did not notice it until I ran the program. Here's what I got...the results are truncated. Cartridge : .270 Win. (SAAMI)
Bullet : .277, 130, Nosler PART SP 16322
Useable Case Capaci: 61.884 grain H2O = 4.018 cm³
Cartridge O.A.L. L6: 3.340 inch = 84.84 mm
Barrel Length : 20.0 inch = 508.0 mm
Predicted Data for Indicated Charges of the Following Powders.
Matching Maximum Pressure: 63000 psi, or 434 MPa
or a maximum loading ratio or filling of 115 %
These calculations refer to your specified settings in QuickLOAD 'Cartridge Dimensions' window.
C A U T I O N : any load listed can result in a powder charge that falls below minimum suggested
loads or exceeds maximum suggested loads as presented in current handloading manuals. Understand
that all of the listed powders can be unsuitable for the given combination of cartridge, bullet
and gun. Actual load order can vary, depending upon lot-to-lot powder and component variations.
USE ONLY FOR COMPARISON !
6 loads produced a Loading Ratio below user-defined minimum of 50%. These powders have been skipped.
Powder type Filling/Loading Ratio Charge Charge Vel. Prop.Burnt P max P muzz B_Time
% Grains Gramm fps % psi psi ms
--------------------------------- -----------------------------------------------------------------
Alliant Reloder-26 105.3 64.6 4.18 3138 99.8 63000 16362 0.970 ! Near Maximum !
Alliant Reloder-25 114.2 64.8 4.20 3106 99.7 63000 15840 0.961 ! Near Maximum !
Norma MRP 106.0 63.1 4.09 3103 98.3 63000 16217 0.968 ! Near Maximum !
Vihtavuori N560 107.7 62.8 4.07 3086 95.0 63000 16252 0.965 ! Near Maximum !
Accurate MAGPRO 108.0 65.5 4.24 3071 93.3 63000 16208 0.971 ! Near Maximum !
IMR 7828 112.1 62.2 4.03 3070 95.5 63000 15763 0.957 ! Near Maximum !
IMR 7828 SSC 106.1 62.2 4.03 3070 95.5 63000 15763 0.957 ! Near Maximum !
Alliant Reloder-22 108.0 62.3 4.04 3069 97.1 63000 15802 0.970 ! Near Maximum !
Alliant Reloder-17 95.2 57.0 3.69 3068 100.0 63000 14592 0.968 ! Near Maximum !
Winchester WXR 110.9 62.6 4.06 3067 96.9 63000 15802 0.970 ! Near Maximum !
Alliant Reloder-23 110.9 61.9 4.01 3062 100.0 63000 14702 0.973 ! Near Maximum !
Ramshot Magnum 107.3 66.7 4.32 3046 97.6 63000 15152 0.962 ! Near Maximum !
Alliant Reloder-16 101.9 56.6 3.67 3043 100.0 63000 14458 0.977 ! Near Maximum !
Ramshot Hunter 100.0 58.9 3.82 3029 99.0 63000 14797 0.974 ! Near Maximum !
Alliant Reloder-19 104.5 59.6 3.86 3027 96.9 63000 15024 0.968 ! Near Maximum !
Winchester 760 94.5 57.0 3.69 3026 98.4 63000 14812 0.975 ! Near Maximum !
Hodgdon H414 94.5 57.0 3.69 3026 98.4 63000 14812 0.975 ! Near Maximum !
Norma URP 99.6 56.2 3.64 3015 99.8 63000 14320 0.979 ! Near Maximum !
Vihtavuori N550 96.7 56.4 3.65 3013 99.7 63000 14448 0.983 ! Near Maximum !
Accurate 4350 98.8 56.3 3.65 3011 99.8 63000 14334 0.995 ! Near Maximum !
Norma 204 99.1 58.4 3.78 3003 96.7 63000 14619 0.968 ! Near Maximum !
IMR 4831 104.5 57.1 3.70 2998 99.8 63000 14043 0.987 ! Near Maximum !
Hodgdon H4831 SC 105.5 60.9 3.94 2996 94.6 63000 14622 0.965 ! Near Maximum !
Hodgdon H4831 109.8 60.9 3.94 2996 94.6 63000 14622 0.965 ! Near Maximum !
Ramshot Big Game 90.1 54.7 3.55 2993 100.0 63000 13690 0.977 ! Near Maximum !
Hodgdon CFE223 85.1 54.1 3.50 2992 100.0 63000 13627 0.978 ! Near Maximum !
IMR 4895 89.8 51.2 3.32 2990 100.0 63000 13703 0.983 ! Near Maximum !
Hodgdon H1000 115.0 64.9 4.20 2987 94.6 60097 15095 0.977 ! Near Maximum !
Accurate 3100 108.0 61.6 3.99 2984 99.0 63000 14225 0.997 ! Near Maximum !
Lovex S071 114.2 61.6 3.99 2984 99.0 63000 14225 0.997 ! Near Maximum !
Hodgdon Hybrid 100V 102.2 56.4 3.65 2983 100.0 63000 13274 0.977 ! Near Maximum !
Alliant Reloder-15 90.6 51.7 3.35 2982 100.0 63000 13666 0.982 ! Near Maximum !
Norma 203B 91.0 51.9 3.37 2979 100.0 63000 13549 0.984 ! Near Maximum !
Winchester Supreme 780 102.8 61.8 4.01 2978 96.7 63000 14226 0.971 ! Near Maximum !
Vihtavuori N165 110.0 62.1 4.02 2977 97.5 63000 14092 0.975 ! Near Maximum !
Hodgdon H380 91.9 53.6 3.47 2973 99.6 63000 13788 0.986 ! Near Maximum !
Lovex S070 99.1 55.9 3.62 2971 98.5 63000 14044 0.987 ! Near Maximum !
Hodgdon H4350 101.8 56.8 3.68 2970 97.8 63000 13944 0.972 ! Near Maximum !
Hodgdon BL-C2 85.6 53.3 3.45 2970 100.0 63000 13317 0.987 ! Near Maximum !
IMR 4350 99.9 56.7 3.67 2970 97.9 63000 13925 0.972 ! Near Maximum !
IMR 4320 92.6 52.0 3.37 2969 100.0 63000 13188 0.968 ! Near Maximum !
Norma 203 old 92.3 53.2 3.45 2968 100.0 63000 13334 0.996 ! Near Maximum !
Hodgdon H4895 87.5 49.9 3.24 2967 100.0 63000 13242 0.981 ! Near Maximum !
Ramshot Wild Boar 86.1 52.5 3.40 2967 100.0 63000 13335 0.978 ! Near Maximum !
Winchester 748 83.2 51.1 3.31 2966 100.0 63000 12921 0.980 ! Near Maximum !
IMR 4955 Enduron 106.7 59.2 3.84 2961 95.0 63000 14156 0.969 ! Near Maximum !
IMR 4451 Enduron 95.6 53.9 3.49 2955 98.3 63000 13672 0.969 ! Near Maximum !
Vihtavuori N160 109.9 60.1 3.90 2955 95.5 63000 13919 0.972 ! Near Maximum !
Lovex S065 98.0 54.7 3.54 2953 99.2 63000 13594 0.986 ! Near Maximum !
IMR 4007 SSC 93.7 54.2 3.51 2951 97.9 63000 13737 0.980 ! Near Maximum !
Ramshot TAC 86.3 53.1 3.44 2951 99.4 63000 13462 0.976 ! Near Maximum !
Hodgdon VARGET 93.5 51.6 3.34 2951 99.9 63000 13154 0.971 ! Near Maximum !
IMR 4064 94.0 50.7 3.28 2945 100.0 63000 12957 0.975 ! Near Maximum !
IMR 3031 89.9 48.0 3.11 2943 100.0 63000 12299 0.987 ! Near Maximum !
Vihtavuori N530 84.6 48.6 3.15 2942 100.0 63000 12699 0.977 ! Near Maximum !
Lovex S062 91.7 50.9 3.30 2938 100.0 63000 12740 0.989 ! Near Maximum !
Accurate 2520 85.5 51.4 3.33 2938 100.0 63000 12564 0.998 ! Near Maximum !
Lovex D073.6 Match Rifle 87.5 51.4 3.33 2938 100.0 63000 12564 0.998 ! Near Maximum !
IMR 8208 XBR 86.6 49.4 3.20 2935 100.0 63000 12589 0.976 ! Near Maximum !
IMR 4166 Enduron 94.8 51.8 3.36 2934 98.4 63000 13281 0.971 ! Near Maximum !
Norma 201 89.0 49.7 3.22 2930 100.0 63000 12671 0.991 ! Near Maximum !
Accurate 4064 91.8 51.2 3.32 2930 100.0 63000 12538 1.015 ! Near Maximum !Since Re26 looked so good in the powder profile, I decided that would be the power that would interest me first. I selected Re26 and ran it, and got this: Cartridge : .270 Win. (SAAMI)
Bullet : .277, 130, Nosler PART SP 16322
Useable Case Capaci: 61.884 grain H2O = 4.018 cm³
Cartridge O.A.L. L6: 3.340 inch = 84.84 mm
Barrel Length : 20.0 inch = 508.0 mm
Powder : Alliant Reloder-26
Predicted data by increasing and decreasing the given charge,
incremented in steps of 0.302% of nominal charge.
CAUTION: Figures exceed maximum and minimum recommended loads !
Step Fill. Charge Vel. Energy Pmax Pmuz Prop.Burnt B_Time
% % Grains fps ft.lbs psi psi % ms
-03.0 103 63.04 3048 2681 57281 16150 99.4 1.014 ! Near Maximum !
-02.7 103 63.23 3059 2702 57976 16181 99.5 1.008 ! Near Maximum !
-02.4 103 63.43 3071 2722 58683 16211 99.5 1.003 ! Near Maximum !
-02.1 104 63.62 3082 2742 59400 16240 99.6 0.997 ! Near Maximum !
-01.8 104 63.82 3094 2763 60128 16268 99.7 0.991 ! Near Maximum !
-01.5 104 64.02 3105 2784 60866 16294 99.7 0.986 ! Near Maximum !
-01.2 105 64.21 3117 2804 61613 16320 99.8 0.980 ! Near Maximum !
-00.9 105 64.41 3128 2825 62373 16344 99.8 0.974 ! Near Maximum !
-00.6 105 64.61 3140 2846 63144 16366 99.9 0.969 ! Near Maximum !
-00.3 106 64.80 3151 2867 63926 16388 99.9 0.963 ! Near Maximum !
+00.0 106 65.00 3163 2888 64717 16408 99.9 0.958 !DANGEROUS LOAD-DO NOT USE!
+00.3 106 65.20 3174 2908 65519 16427 99.9 0.953 !DANGEROUS LOAD-DO NOT USE!
+00.6 107 65.39 3186 2930 66336 16444 100.0 0.947 !DANGEROUS LOAD-DO NOT USE!
+00.9 107 65.59 3197 2951 67169 16460 100.0 0.942 !DANGEROUS LOAD-DO NOT USE!
+01.2 107 65.79 3209 2972 68010 16475 100.0 0.936 !DANGEROUS LOAD-DO NOT USE!
+01.5 108 65.98 3220 2993 68864 16489 100.0 0.931 !DANGEROUS LOAD-DO NOT USE!
Results caused by ± 10% powder lot-to-lot burning rate variation using nominal charge
Data for burning rate increased by 10% relative to nominal value:
+Ba 106 65.00 3332 3204 82416 15664 100.0 0.870 !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba 106 65.00 2911 2446 50083 16232 94.6 1.073 My own approach to using these solutions is to look at the velocity associated with a certain pressure level, and do my initial load tests with a chronograph to see where my limit might be. In this case, I'd tell myself "QL says 3150 fps indicates about 64000 psi." In practice, I would consult loading manuals and on-line data to see if this looks reasonable. In this case I probably would not go beyond 3140 fps. But then again, I would never have a 20-inch .270, either. 
Don't be the darkness.
America will perish while those who should be standing guard are satisfying their lusts.
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Campfire Tracker
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Campfire Tracker
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Sorry if this is redundant but I think QL is calculating on the case capacity only, which increases with longer seating. QL is helpful to set a maximum velocity but you could get in trouble if you take the charge weights as Gospel.
"When you disarm the people, you commence to offend them and show that you distrust them either through cowardice or lack of confidence, and both of these opinions generate hatred." Niccolo Machiavelli
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Campfire Outfitter
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It will account for OAL changes and resulting changes in volume under the bullet. That can make a substantial difference, too. I can seat 95-grain Partitions out to about 2.90" OAL in my 6-284 while the default value in QL for that bullet is closer to 2.50 inches, and because of that I can get quite a bit more out of the load. At the same time, when you are seating out far enough to get very close to the lands, you adjust the Start Pressure to predict how peak pressure is going to be affected.
There are cartridges known to not be QL-friendly, but I don't recall what they are since I don't own one...with the exception of a 6.5 Grendel. That one requires special treatment.
One thing is for sure, though: when using QL always compare results to published data if available. You definitely cannot just take the charge/pressure outputs as gospel. QL results should be carefully considered. They are NOT published loading data.
Don't be the darkness.
America will perish while those who should be standing guard are satisfying their lusts.
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