Post by Lee Martin on May 7, 2012 10:40:17 GMT -5
A lot of writers and experts frown upon really heavy bullets in the 500 Linebaugh. 450 grains seems to be the prescribed max. And while they’ve yet to provide the “why”, they’ve hinted at three reasons: 1) They won’t stabilize and aren’t as accurate as 420’s – 450’s, 2) They ramp pressure and even cause sporadic pressure spikes, and 3) They under-penetrate the lighter bullets. I never bought into any of this.
Whitworth and I have been working with our 500 Maximums a lot this year and learned a few things. We both agree 435’s are way small for the round. I equate 435’s in a 500 Maximum to 158’s in the 357 SuperMag. They work but you’re trying to make a ‘deathray’ out of it with light slugs. Consider this. 435 WFNs penetrate best around 1,200 – 1,300 fps. 1,300 – 1,500 nets you nothing. Over 1,500 fps and the meplat may deform lessening performance. Sure, you can download the Maximum to 1,200 – 1,300 fps. But at that point you might as well opt for the lighter Linebaugh.
Unfortunately most published 500 Max data stops with 435’s at 1,550 fps. Rarely do we get top-end loads for anything heavier. If we limit the round like this we’re making the same mistake we made with the 357 Maximum. Just shoot the standard bullet but run it 200 – 300 fps faster. Flatter trajectory, yes. Added performance, no.
I consider 500 – 525 grains to be ideal for the Maximum. Take Cast Performance’s 525 WFN for example. Over 38.0 grains of AA1680 it’ll go 1,300 – 1,350 fps. It adds 90 grains of weight to the Linebaugh WFN and another 50 – 100 fps. Better yet, recoil is no worse than 435’s at 1,500 fps. Pressure is under 35,000 PSI so we’re not taxing the gun either. And then there’s the accuracy potential. This group was fired at 50 yards off the best using this combination:
I have other 50 yard groups that print well under 3 inches. No doubt these guns and this load shoot better than I can hold. Extraction is effortless and with a hard roll crimp bullet jump isn’t a problem.
Now let’s talk penetration. For years we’ve be told the 475 Linebaugh out penetrates the 500 Linebaugh. And when you restrict the 500 to 435’s that’s true. The problem is the 435 handicaps the half-bore. Take a look at these three bullets. Left to right – 425 WFN 475, 435 WFN 500, 525 WFN 500:
Sectional densities are as follows;
425 WFN 475 = 0.268
435 WFN 500 = 0.238
525 WFN 500 = 0.287
The 435 just isn’t long enough to wring the most of the 500. Add some sectional density and look out. Moreover, real world shooting supports this. 500 – 525 WFNs have out-bored 435’s on test medium and big game alike (I’m talking very reliable, very experienced sources here). And that’s from the base 500 Linebaugh. Load the same bullet in the Maximum and Thor’s hammer gets juiced.
Whitworth and I will be conducting penetration and accuracy tests with 525 WFNs in the Linebaugh and Maximum. Our baseline will be 420’s @ 1,400 fps from the 475 and 435’s at 1,250 fps from the 500L. We’ll hold 525’s to 1,100 fps in the Linebaugh and 1,300 – 1,350 in the Max. Whit will also report on how they perform in field.
I’m not trying to create waves here but do believe it’s time we take a harder look at the 500’s (especially the Maximum). When unveiled in the early 90’s it was touted as a powder hungry, bone-breaking, eyeball rattling howitzer. And if all it does is push standard 500 Linebaugh bullets 250 fps faster, what’s the point? All of that downside for another 2 to 3 inches of penetration? No thanks. But again, that argument is very short sighted. Ignoring heavyweight bullets in these guns defeats the purpose. In fact, the same can be said of penning the Linebaugh to 450 or less.
So I’d like to see folks embrace 500 – 525 grains in not only the Maximum but the 500 Linebaugh too. Hopefully our tests will promote these weights. I’m sure there’s a counter argument to my theory and I welcome it. Just be sure that argument is substantiated with real data.
Thanks for listening and stay tuned.
-Lee
www.singleactions.com
"Building carpal tunnel one round at a time"
Whitworth and I have been working with our 500 Maximums a lot this year and learned a few things. We both agree 435’s are way small for the round. I equate 435’s in a 500 Maximum to 158’s in the 357 SuperMag. They work but you’re trying to make a ‘deathray’ out of it with light slugs. Consider this. 435 WFNs penetrate best around 1,200 – 1,300 fps. 1,300 – 1,500 nets you nothing. Over 1,500 fps and the meplat may deform lessening performance. Sure, you can download the Maximum to 1,200 – 1,300 fps. But at that point you might as well opt for the lighter Linebaugh.
Unfortunately most published 500 Max data stops with 435’s at 1,550 fps. Rarely do we get top-end loads for anything heavier. If we limit the round like this we’re making the same mistake we made with the 357 Maximum. Just shoot the standard bullet but run it 200 – 300 fps faster. Flatter trajectory, yes. Added performance, no.
I consider 500 – 525 grains to be ideal for the Maximum. Take Cast Performance’s 525 WFN for example. Over 38.0 grains of AA1680 it’ll go 1,300 – 1,350 fps. It adds 90 grains of weight to the Linebaugh WFN and another 50 – 100 fps. Better yet, recoil is no worse than 435’s at 1,500 fps. Pressure is under 35,000 PSI so we’re not taxing the gun either. And then there’s the accuracy potential. This group was fired at 50 yards off the best using this combination:
I have other 50 yard groups that print well under 3 inches. No doubt these guns and this load shoot better than I can hold. Extraction is effortless and with a hard roll crimp bullet jump isn’t a problem.
Now let’s talk penetration. For years we’ve be told the 475 Linebaugh out penetrates the 500 Linebaugh. And when you restrict the 500 to 435’s that’s true. The problem is the 435 handicaps the half-bore. Take a look at these three bullets. Left to right – 425 WFN 475, 435 WFN 500, 525 WFN 500:
Sectional densities are as follows;
425 WFN 475 = 0.268
435 WFN 500 = 0.238
525 WFN 500 = 0.287
The 435 just isn’t long enough to wring the most of the 500. Add some sectional density and look out. Moreover, real world shooting supports this. 500 – 525 WFNs have out-bored 435’s on test medium and big game alike (I’m talking very reliable, very experienced sources here). And that’s from the base 500 Linebaugh. Load the same bullet in the Maximum and Thor’s hammer gets juiced.
Whitworth and I will be conducting penetration and accuracy tests with 525 WFNs in the Linebaugh and Maximum. Our baseline will be 420’s @ 1,400 fps from the 475 and 435’s at 1,250 fps from the 500L. We’ll hold 525’s to 1,100 fps in the Linebaugh and 1,300 – 1,350 in the Max. Whit will also report on how they perform in field.
I’m not trying to create waves here but do believe it’s time we take a harder look at the 500’s (especially the Maximum). When unveiled in the early 90’s it was touted as a powder hungry, bone-breaking, eyeball rattling howitzer. And if all it does is push standard 500 Linebaugh bullets 250 fps faster, what’s the point? All of that downside for another 2 to 3 inches of penetration? No thanks. But again, that argument is very short sighted. Ignoring heavyweight bullets in these guns defeats the purpose. In fact, the same can be said of penning the Linebaugh to 450 or less.
So I’d like to see folks embrace 500 – 525 grains in not only the Maximum but the 500 Linebaugh too. Hopefully our tests will promote these weights. I’m sure there’s a counter argument to my theory and I welcome it. Just be sure that argument is substantiated with real data.
Thanks for listening and stay tuned.
-Lee
www.singleactions.com
"Building carpal tunnel one round at a time"
Beware the fact that it is easy to reach the right conclusion when you know up front which conclusion you want to reach. Keep good records and make sure you stay objective. We all know that the standard bullet weight/velocity paradigms fade away when the big bore cast bullet cartridge steps up to the plate.
