Lead melter
03-17-2008, 10:07 AM
As a few of you know that have tried to follow this testing, I sarted the idea to see just how fast a pure lead boolit could be driven with a standard degree of accuracy. My standard was a 4" group at 100 yards.
My test results are not claiming to be conclusive...they are simply my results using one boolit, one size, one gas check, one rifle, etc. Others tests can, and I'm sure, will have different results.
As most of us know, fast pistol/shotgun powders, like Unique and Red Dot, seem to result in great accuracy with cast boolits, but pressures usually reach a max before the velocity max is reached. I attempted to find velocity max with common rifle powders.
For the sake of space, I will not try to again give the data found. This can be seen of previous posts concerning this test.
http://castboolits.gunloads.com/showthread.php?t=26464
http://castboolits.gunloads.com/showthread.php?t=26464
With Win 748 velocity and accuracy figures were all over the spectrum. Much too inconsistant to consider when running a boolit of pure lead at velocities that would allow any accuracy. As powder charges increased, velocity levels fell more in normal ranges, but accuracy went south in a hurry.
IMR-3031 seemed to do somewhat better, with 50 yard groups looking promising, and 100 yard groups at or very near the 4" standard I stated with 3 reduced loads.
AA-5744 increased the accuracy level, but with somewhat lower velocities. Also promising were 3 reduced loads that progressed to the 100 yard mark with accuracy right at the standard level.
H-4198 was the overall winner of the tested powders. Fantastic accuracy from the lowest end of published data, to the last load at 100 yards that met accuracy standard even though the load was over published data.
What resulted, at least in my findings, is that the pure lead boolit seems able to maintain accuracy up to the 1400-1450 fps level. After that point is reached, the accuracy levels become verry erratic. Some groups fell within the standard, but with no real degree of consistancy.
"The Reload Bench" site gives powder burn rates from fastest to slowest with a numeral assigned to each...1 being fastest. Looking at this chart I find that ;
Red Dot-10
Unique-35
AA5744-78
H-4198-86
IMR-3031-94
Win 748-103
It appears that powder burn rate has a lot to do with performance on pure lead boolits.
Other powders that fall within this range are;
Herco-45
2400-67
H110-71
Win 296-72
H-4227-76
All of which may be found to be suitable powders, although load density problems may arise with H110 and 296.
I'm sure boolit fit, nose design, lube, load density, boolit diameter, rifling, shooter, the list could go on forever, all will have a bearing on other tests. The only thing I tried to do was "dance with the one that brought me".
End result: Did I just reinvent the wheel, as the old buff' hunters fired huge chunks of lead at the same velocities without any real problems?
Is there a place for my findings? Possibly. Small game hunters, pest erradication, instances where expansion is paramount, fur harvesters, old time hunt re-enactments, links with the past? I don't know, you'll have to decide for yourself.
One intersting note; With the particular boolit I chose, I never had any real problem with leading at any velocity. The GC seems to have eliminated that issue. Would a PB boolit do as well? You decide that as well.
My test results are not claiming to be conclusive...they are simply my results using one boolit, one size, one gas check, one rifle, etc. Others tests can, and I'm sure, will have different results.
As most of us know, fast pistol/shotgun powders, like Unique and Red Dot, seem to result in great accuracy with cast boolits, but pressures usually reach a max before the velocity max is reached. I attempted to find velocity max with common rifle powders.
For the sake of space, I will not try to again give the data found. This can be seen of previous posts concerning this test.
http://castboolits.gunloads.com/showthread.php?t=26464
http://castboolits.gunloads.com/showthread.php?t=26464
With Win 748 velocity and accuracy figures were all over the spectrum. Much too inconsistant to consider when running a boolit of pure lead at velocities that would allow any accuracy. As powder charges increased, velocity levels fell more in normal ranges, but accuracy went south in a hurry.
IMR-3031 seemed to do somewhat better, with 50 yard groups looking promising, and 100 yard groups at or very near the 4" standard I stated with 3 reduced loads.
AA-5744 increased the accuracy level, but with somewhat lower velocities. Also promising were 3 reduced loads that progressed to the 100 yard mark with accuracy right at the standard level.
H-4198 was the overall winner of the tested powders. Fantastic accuracy from the lowest end of published data, to the last load at 100 yards that met accuracy standard even though the load was over published data.
What resulted, at least in my findings, is that the pure lead boolit seems able to maintain accuracy up to the 1400-1450 fps level. After that point is reached, the accuracy levels become verry erratic. Some groups fell within the standard, but with no real degree of consistancy.
"The Reload Bench" site gives powder burn rates from fastest to slowest with a numeral assigned to each...1 being fastest. Looking at this chart I find that ;
Red Dot-10
Unique-35
AA5744-78
H-4198-86
IMR-3031-94
Win 748-103
It appears that powder burn rate has a lot to do with performance on pure lead boolits.
Other powders that fall within this range are;
Herco-45
2400-67
H110-71
Win 296-72
H-4227-76
All of which may be found to be suitable powders, although load density problems may arise with H110 and 296.
I'm sure boolit fit, nose design, lube, load density, boolit diameter, rifling, shooter, the list could go on forever, all will have a bearing on other tests. The only thing I tried to do was "dance with the one that brought me".
End result: Did I just reinvent the wheel, as the old buff' hunters fired huge chunks of lead at the same velocities without any real problems?
Is there a place for my findings? Possibly. Small game hunters, pest erradication, instances where expansion is paramount, fur harvesters, old time hunt re-enactments, links with the past? I don't know, you'll have to decide for yourself.
One intersting note; With the particular boolit I chose, I never had any real problem with leading at any velocity. The GC seems to have eliminated that issue. Would a PB boolit do as well? You decide that as well.