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According to my QL, I get 70672 PSI and 2999 FPS MV with a SAAMI spec and a 28" barrel
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Check out GRT if you haven’t already, may not be as good as quick load but it’s free and I enjoy messing around with it
Link?
start [Gordons Reloading Tool Community]
www.grtools.de what he saidstart [Gordons Reloading Tool Community]
Well, played around with it, and it velocities run a good 90-150 fps faster than my Garmin says. It doesn't account for primers? And I have Forster benchrest dies, not as good as mandrel and bushing, no annealer, so neck tension is iffy. 300 blackout
Make sure you’re measuring each of your components and inputting that data, especially case capacity. Do t just rely on the default values. If you have data from a known charge there’s a tab you can go in and input that and it will then true the burn rate and should be pretty close for all its other predictions.
Never did that. What's the best way to measure capacity? Thanks.
ETA: I'll try the upside down spent primer method
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Jam generally has the highest pressure.
As long as your not seating the bullet in the case super far (decreasing volume, thus increasing pressure) than I don’t think it would do anything bad pressure wise; but if you are that would definitely drive pressure up. I can’t tell you for certain that anything bad won’t happen as that’s a lot longer of a jump than iv ever messed with, there may be something I’m overlooking.
As long as your not seating the bullet in the case super far (decreasing volume, thus increasing pressure) than I don’t think it would do anything bad pressure wise; but if you are that would definitely drive pressure up. I can’t tell you for certain that anything bad won’t happen as that’s a lot longer of a jump than iv ever messed with, there may be something I’m overlooking.
Highly recommend not thinking in terms of "jump". Certainly, to start of with, you'll want to know where your lands is, typically because you either don't want to jam a bullet or you do want to jam a bullet. Knowing where the lands is helps you decide on where you want to start. . . like .010, .020, .030, .060 or whatever. Otherwise, focus on seating depth and forget about jump.
As to your question . . . seating to touch or into the lands does increase starting pressure significantly. Seating to less than .010" from the lands tends to make significant increases in pressure. Anything further back affects pressure, but not enough to counter the effect of blowby (why we see some decrease in velocity/pressure as we seat deeper into the case making for less case capacity). So, amount of "jump" typically has very little effect, where seating depth is a biggy. .250" jump is probably not big deal, depending on how far the bullet is seated into the case (like compressing the powder charge???).
It’s been very accurate for my long freebore .223 bolt. Not sure what’s going on there. Oh well, was worth a try.
My first crack at something like this, I'm probably missing a parameter or something.
There are a bunch of tutorial videos for it. It is not the most intuitive program to use.
Double check the book value for COAL. QL is showing 2.260 for that same load, which is quite a bit longer than the 2.070 I see on your screenshot. Max pressure is only 40761 and velocity is 2088. QL also shows that load to stop burning before the bullet exits the muzzle on a 28" barrel.
This is why I got QL, to play around with different parameters to learn things
I did, Lyman AR Reloading handbook 2nd edition. 2.075.
Interesting. I checked my Hornady book...for that bullet it shows 2.090 COAL with maximum safe load of 15.7 gr Lil Gun. But it also states a maximum of 2.260 COAL for the cartridge which is what QL is showing. Maybe that's magazine maximum?
Seems to show it's best to look at mutliple sources for information....
with QL, case capacity is important, but the Shot Start (Initiation) Pressure is quite important too and affects predicted velocity and psi - and from what I learned its tightly corelated with so called "neck tension". Then the Ba.
The shots start pressure is mainly correlated with where you are in relation to the lands and as long as you stay away from them, you can leave it at the default value.
The vast majority of the time with quick load, I am getting velocities that are way higher than what it predicts, but not getting high pressure. Whenever I have adjusted the start pressure, it did not affect my velocity appreciably it just made the pressure even higher, which exacerbates rather than alleviates the discrepancy that I most frequently encounter.
As others have stated, to get things to line up you have to change the powder burn parameters
I find QL most useful for getting a ballpark idea of what a the effect will be of changing one variable when starting from a known set of parameters. For example, if I’m at 135 grains of H50BMG, no pressure signs and a given velocity, what will the ballpark velocity gain of 2 grains more powder or two more inches of barrel, or changing to RL50 at a load predicted to give the same pressure?
I have NOT found it useful for starting from scratch and predicting results. Whenever I try that, this is what happens: it tells me I can put in 142 grains of H50BMG and be below max pressure and get 2800 fps (Cheytac). But I run into pressure at 136 grains, and get 2900 fps with 134 grains. So I always start well below what QL says will be a max load. This is the opposite of the published reloading data where I can usually start at/near a max load and go higher.
The vast majority of the time with quick load, I am getting velocities that are way higher than what it predicts, but not getting high pressure. Whenever I have adjusted the start pressure, it did not affect my velocity appreciably it just made the pressure even higher, which exacerbates rather than alleviates the discrepancy that I most frequently encounter.
As others have stated, to get things to line up you have to change the powder burn parameters
I find QL most useful for getting a ballpark idea of what a the effect will be of changing one variable when starting from a known set of parameters. For example, if I’m at 135 grains of H50BMG, no pressure signs and a given velocity, what will the ballpark velocity gain of 2 grains more powder or two more inches of barrel, or changing to RL50 at a load predicted to give the same pressure?
I have NOT found it useful for starting from scratch and predicting results. Whenever I try that, this is what happens: it tells me I can put in 142 grains of H50BMG and be below max pressure and get 2800 fps (Cheytac). But I run into pressure at 136 grains, and get 2900 fps with 134 grains. So I always start well below what QL says will be a max load. This is the opposite of the published reloading data where I can usually start at/near a max load and go higher.
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Agreed. It’s a very handy tool if you use it to test things at a pretty coarse level. It saves me a lot of time choosing which powders to test, and gives me a rough idea about pressure and velocity. But it’s not ground truth, only prediction. Sure, it can be tuned to give you more accurate results to the ground truth, but that can take a lot of work and be localized to a single cartridge.
Yeah, by the time you already know what the load does and you’re trying to get quick load to align with that reality, you’re already done. It’s quick loads problem at that point not yours.
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