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Discussion Starter · #1 ·

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Excellent Paul, you have no idea of how much time I spent going through the charts to gather that information. Is there a way you can note what you are using as the basis for the maximum performance range. Is it just the velocity of the bullet and if so, will it be bullet specific since my memory of the figures published seem to recall part of the performance range being determined by a blanket statement by DocGKR that bullets were fragmenting/upsettig above a certain velocity. Will this be more specific?

Also, if the users are like me, they are reading the numbers to figure out how long a barrel they need for a particular performance objective. Is there any way to get a rough range of velocities in there? Might be misleading given the variety of loadings and range of velocities for the same barrels, so that might be a bad idea, or at least one to handle carefully.
 

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Looks good so far. What about putting the velocity at the graduated distances, too?
 

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Looks good Paulo,
you probably should label the top row as muzzle vel.
The biggest thing is to add your assumptions/parameters... Bore height altitude temp etc
define what max perf range is too
I'm a big fan of OGW, maybe a ogw200 and 400 range along with max perf or 1 k ft lbs range.
You asked for it.

Also what is your main focus and audience for the chart?
 

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The maximum performance range is based on 1000 ft/lbs of energy
I think you're misreading that. Notice that the maximum performance is on a different line and is a longer range than that of the line marked "1K foot pounds." Off the top of my head those numbers looks like the point at which the bullet will fragment or dirupt. Nice touch, he gives both the maximum defensive (maximum performance range) and ethical hunting ranges (1 K foot pounds).
 

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Discussion Starter · #9 ·
Once I am done, I will have a legend on the bottom explaining things.
I'm using a sight height of 2.6" and an altitude of 1000 feet.

The maximum performance range is the range in which the bullet will still fragment/expand.

The chart is just a quick reference. I really can't attach the barrel length to any velocity because it would be too complicated.
I'll see if I can add the velocity to the yards without taking up too much space.
 

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Once I am done, I will have a legend on the bottom explaining things.
I'm using a sight height of 2.6" and an altitude of 1000 feet.

The maximum performance range is the range in which the bullet will still fragment/expand.

The chart is just a quick reference. I really can't attach the barrel length to any velocity because it would be too complicated.
I'll see if I can add the velocity to the yards without taking up too much space.
Barrel legnth shouldn't factor into this since it's the starting velocity that's important and not the barrel legnth. Looks good with the added velocities.
 

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Barrel legnth shouldn't factor into this since it's the starting velocity that's important and not the barrel legnth. Looks good with the added velocities.
Really depends on what the target audience is and what question you're trying to communicate. What Paul has defined is a nice subset that clearly answers a portion of the picture. It does that clearly and in a single resource which is fantastic. Barrel length selection becomes a two part question. This tells you how fast it needs to go at the muzzle to achieve an effect at a given distance. Then you have to descend into a whole 'nother mess of data in order to figure out what barrel will probably give you that velocity.I know I was going back and forth between every post I could find with velocity for a projectile versus given barrel lengths to figure out how long my SBR should be. When it finally gets in we'll get to see how well I extrapolated... :a16:

ETA - It might also be interesting to throw a few 5.56 rounds in there for comparison. Depends on whether or not you want to compare/contrast the effective ranges for those thinking about adopting the cartridge. From discussions I've had with owners of 5.56 weapons, it's amazing the ranges they believe their weapon is effective to. I've had owners of 11" 5.56 tell me their weapon would disrupt/expand/fragment to 300 yards.
 

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I have the Barnes 85 GR TSX done.
One question P, are you going to show realistic speeds for the bullets or just run numbers? For instance an 110gr AccuBond at 3250 fps would be quite impressive but it isn't going to happen in the real world out of a 6.8 SPC. I notice your headings vary a bit between the completed load and the new ones but I'm not sure if this is a statement of intent or the appropriate speeds changed when you ran the numbers.
 

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Discussion Starter · #15 ·
One question P, are you going to show realistic speeds for the bullets or just run numbers? For instance an 110gr AccuBond at 3250 fps would be quite impressive but it isn't going to happen in the real world out of a 6.8 SPC. I notice your headings vary a bit between the completed load and the new ones but I'm not sure if this is a statement of intent or the appropriate speeds changed when you ran the numbers.
Realistic speeds. With the Accubonds, I'll start at 2200 FPS and stop at 2700 FPS, which is the speed out of an 8" PSD to a 20" Barrel.
 

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Really depends on what the target audience is and what question you're trying to communicate. What Paul has defined is a nice subset that clearly answers a portion of the picture. It does that clearly and in a single resource which is fantastic. Barrel length selection becomes a two part question. This tells you how fast it needs to go at the muzzle to achieve an effect at a given distance. Then you have to descend into a whole 'nother mess of data in order to figure out what barrel will probably give you that velocity.I know I was going back and forth between every post I could find with velocity for a projectile versus given barrel lengths to figure out how long my SBR should be. When it finally gets in we'll get to see how well I extrapolated... :a16:

ETA - It might also be interesting to throw a few 5.56 rounds in there for comparison. Depends on whether or not you want to compare/contrast the effective ranges for those thinking about adopting the cartridge. From discussions I've had with owners of 5.56 weapons, it's amazing the ranges they believe their weapon is effective to. I've had owners of 11" 5.56 tell me their weapon would disrupt/expand/fragment to 300 yards.
I see what you mean. I was only figuring on the reader already knowing what the velocity was on their particular rifle instead of looking for a barrel that would give a certain velocity.
 

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Can you guys look at the above link and let me know what you think.
I think this is a fantastic reference and I think you are stepping above and beyond again.

Thank you!
 
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