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February - March 2003 Volume 38, Number
1 ISSN: 0017-7393 Number 221 |
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On the
cover... The Kimber Stainless Target II is chambered for the .38 Super. Photo by Stan Trzoniec. Pronghorn photo by John R. Ford. |
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Handloading -
A Game of Wit
Since the name of this publication
is Handloader, we tend to receive a lot of correspondence regarding handloading. Questions
run the gamut from recommended loads for any one of hundreds of wildcat and standard
cartridges to requests for loads using any number of component combinations that are not
found in standard loading references - such as Swift, Speer, Hodgdon, Sierra, Nosler,
Barnes, Lyman, Alliant, Vihtavuori, Hornady, Accurate, etc. Of course, we also have 221
issues of Handloader to rely on, not to mention Ken Waters Pet Loads, which covers a
variety of wildcats, in addition to the majority of factory cartridges.
But as extensive as the list of
references above might seem, it only serves as the tip of the iceberg, so to speak. There
have been 27 Hodgdon manuals, 13 from Speer, 47 or so from Lyman and 5 each from Nosler
and Hornady. There was even a Cast Bullet Manual from RCBS a few years back. There was
also a series of manuals from the old Lyman-Ideal partnership.
The most interesting fact regarding
this vast source of reference material for handloading is that until just a few years ago,
none of the loads were pressure tested. Nope, none were fired in any sort of standard
reference barrel, not CUP, psi or CIP. All that data was the result of plain, old,
painstaking hard work, miking case head expansion and comparing notes for factory loads
that produced similar performance, both in terms of pressure and velocity. Call it an
educated guess, but nevertheless, a guess.
So in reality, it was left to
Winchester, DuPont, Hercules, Remington, Norma, etc. to provide a solid base for the
industry pressure standard. And it is probably easy to understand how Vernon Speer, for
example, managed to publish eight manuals without a single pressure barrel. He did it with
a modest dose of common sense, ingenuity and no small amount of risk. Then, too, there was
really no other choice if Speer was going to sell bullets. The same could be said of
Swift, Barnes, Hornady, Sierra, Nosler and other bullet manufacturers today - especially
when you consider the broad variation in bullet design nowadays. Weve harped on it
time and time again, but it is pure folly to use just any old load information for a lead
core bullet if you intend to use a Partition, Barnes X-Bullet, Swift A-Frame, Winchester
Fail Safe, etc.
The point of all this is that much
of the older loading information that was published over the years was developed without
any pressure testing equipment. The exception, and it may not be the only one, is Phil
Sharpes Complete Guide to Handloading, which cited a wealth of loads for wildcats
and standard cartridges using pressure data from DuPont and Hercules. But even then, some
of that data wouldnt pass muster in todays lawyer-infested society.
Heres an example. Browsing
though Sharpes reference work I glanced down the long list of loads for the .44
Smith & Wesson Special. For a 242-grain Sharpe hollowpoint with a seating depth of
.307 inch, he lists 18.0 grains of Hercules 2400 at 1,070 fps at 15,000 psi and 20 grains
at 1,200 fps at 19,700 psi. Further down the list, there are no loads listed for 2400 with
the Lyman 429421 semiwadcutter Keith bullet, but there is a listing for 2400 with the
factory bullet, presumably the 247-grain roundnose lead alloy slug, over 18.0 grains of
2400 for 1,080 fps at 13,500 psi and 18.4 grains for 1,100 fps and 15,000 psi. All loads
were fired in a 6.5-inch barrel, but none were recommended by Hercules, which made the
powder.
Of course, in addition to Sharpes
loads, most .44 Smith & Wesson Special fans can recite Elmer Keiths loads - 18.5
grains of 2400 in ballonhead cases and 17.5 grains with solid head brass, with Elmers
429421 cast 250-grain semiwadcutter. Both loads supposedly ran upwards of 20,000 psi in
the New Century Smith & Wesson Triple Lock, Colt New Service and Colt Single Action
Army and were listed in older Ideal and Lyman manuals. Of course, Keith wrote about these
loads in a variety of publications over the years. In short, there was no mystery about
Elmers loads; they were accepted as fact.
Now lets fast forward to 2002 in the
Speer ballistic laboratory using the RCBS copy of Elmers semiwadcutter at 250 grains
with a CCI 300 primer and currently manufactured 2400 (now Alliant) fired in a SAAMI
piezo-electric P/V (pressure/velocity) barrel.
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From Speers ballistic report,
we can derive a couple conclusions, possibly more. First, the Smith & Wesson New
Century (aka Triple Lock) was a lot stronger than we might like to believe. The same goes
for the Colt Single Action Army of the period. Regardless, Sharpe and Keith were a bit
conservative when it came to estimating pressure with their pet loads. Although it is
interesting that Keith was very close when he cited pressure for his loads in the solid
head and ballonhead case as similar, Speer tests show they are similar at 27,048 and
26,682, respectively, albeit about 7,000 psi over Keiths estimate.
I suppose some might wonder if the
difference between Keiths estimated pressure and Speers report is significant.
After all, Elmer used those loads in the .44 Special for a number of years. Then too, when
you stop to realize that the Smith & Wesson New Century cylinders were not heat
treated and were somewhat smaller in diameter than those used in the Second Model and
thereafter, it is a wonder those old sixguns didnt come apart, or at very best,
loosen up inside.
Analysis of Keiths loads on
modern pressure testing equipment might also make one wonder about other loads that Keith
published over the years. One that comes immediately to mind is 18.5 grains of 2400 with
the Lyman 454424 Keith semiwadcutter in the .45 Colt. Speer stops at 18.0 grains of 2400
with its 260-grain jacketed hollowpoint in loads listed for the Ruger and Thompson/Center
Contender at upwards of 25,000 psi. Admittedly, you can honestly expect a 255- to
260-grain cast semiwadcutter to develop less pressure than a jacketed hollowpoint, all
other things being equal, but 18.5 grains of 2400 with a similar weight cast bullet would
appear to be pushing things a bit - awfully close to 25,000 psi. If thats enough
pressure to dismantle a Colt SAA, I dont know, but years of experience with the .45
Colt certainly suggest it will cause wear and tear on the cylinder pin and bushing.
When you stop to consider the
thickness of the .45 Colt cylinder wall under the stop notch is a mere .009 to .012 inch,
fair-minded folks might have cause for concern. Yes, I know some folks report the use of
18.5 grains of 2400 in the .45 Colt with the Keith 454424 semiwadcutter for years, but the
fact remains, 25,000 psi is a bit more than double the industry .45 Colt standard of
14,000 psi.
So, how is it that some folks so
eagerly recommend Elmers loads in the .44 Special and .45 Colt? One wonders,
especially in light of modern pressure tested loads. Then too, Ive even used Elmers
loads a couple times, in Colts and custom Rugers, but I sure wouldnt subject my pet
sixguns to a steady diet of those concoctions.
The point of all this is that we
have received a number of letters, facsimiles and e-mails over the years from concerned
readers who complain that loading information from popular sources has been routinely
reduced over the years - not just for the .44 Special and .45 Colt, as described above,
but for a variety of cartridges, handguns and rifles alike. One reader wrote to complain
that the .38 Special was but a mere figment of its former self. Others complained the .35
Whelen was standardized by Remington at lower pressures than handloaders had been using
when it was a wildcat, ostensively to satisfy the legions of lawyers that run the
industry. The list goes on and on, including the .257 Roberts and other cartridges that
started out as wildcats.
The truth is, as pressure testing
methods have matured over the years, ballistic labs are finding historical loading
information for a broad selection of cartridges was a bit off the mark - in some
instances, way off.
Take for example, the .256 Newton. A
load from a dated reference blew one of Newtons rifles to pieces recently and
subsequent research suggests data from a variety of pre-pressure barrel sources were
bombs. Then we find that the .458 Lott has been the source of mythical load data as well.
Are folks so enamored by an increase of 50 to 100 fps in velocity they are willing to risk
life and limb to prove they have more testosterone than some technician in a ballistic
lab?
Not only have pressures become standardized
with modern testing equipment, there is at least one other factor to consider in review of
current loading manuals - hunter demand for premium bullet designs has brought about a
modest reduction in published data. To wit, it used to be that you could substitute just
about any old lead core hunting bullet for another and not get into trouble with excess
pressures - assuming you didnt do something radically stupid. But the advent of
newer designs has, as a rule, resulted in longer bullets by virtue of thicker jackets,
solid copper sections or entirely copper construction. Presently, a 130-grain Swift
Scirocco is about the same length as the old 150-grain semispitzer or roundnose .270 WCF
bullet. Since any bullet must be seated to conform to overall loaded length standards,
longer bullets must be seated deeper in the case, effectively reducing powder capacity.
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As a case in point, the early
accuracy problems with the .257 Roberts were due largely to the simple fact no one had
figured out how to produce a well-balanced spitzer bullet. Ned Roberts complained that
until someone did, he was effectively stuck with roundnose bullets if he expected any kind
of respectable accuracy. Since a roundnose 117-grain bullet is a lot shorter than a
spitzer of similar weight, early loads for the Remington-Roberts had more velocity
potential - assuming equal pressure - than later loads with longer 117-grain lead core
spitzers, or premium bullets like the Swift Scirocco, Barnes X-Bullet or Nosler Partition.
A review of Ned Robertss loads with IMR-4064 and IMR-3031 proves it. Some of those
combinations would lock the bolt down with todays premium bullet designs. And it
wouldnt matter if it was a short or long action since common sense would suggest the
bullet should be seated to a depth of at least one caliber to ensure proper neck tension.
Another problem is the result of the
myriad of bullet designs that might be available in one weight for any given caliber. For
example, Speer offers six 150-grain, .30-caliber bullets, five at 180 grains. In both
weight ranges, the spitzer boat-tail designs are the longest; the roundnose bullets are
the shortest. Hunters want boat-tails so, by default, are accepting limited powder
capacity when compared to flatbase or roundnose bullets. The irony is roundnose bullets
actually offer the greatest velocity potential, but hunters reject them in large part for
the more streamlined (higher ballistic coefficient) designs.
Adding fuel to the fire is the fact
that Speer prints loads for bullets that produce the highest average pressures - usually
spitzer boat-tails - so it doesnt have to publish data for six different 150-grain,
.30-caliber bullets in a dozen cartridges.
The same problem crops up at Sierra,
Nosler and Hornady - they simply have too many bullets to test all of them with a
reasonable selection of powders/components.
So, hunters demands for more
streamlined, high-performance bullet designs has, in effect, resulted in a modest drop in
velocity potential. I say modest because that is about all it is - save for some folks who
scream bloody murder if their pet cartridge is listed in some manual with a maximum load
that is 50 or 60 fps slower, or the maximum load is reduced one grain below what they
think it should be.
In addition, there was a time when
folks tested loads in longer barrels, vice the 22- and 24-inch non-magnum and magnum
standards presently. So back in 1954 some manual might have listed loads for the .30-06 in
a 24-inch barrel and gotten 50 to 100 fps more velocity than we might achieve in a 22-inch
barrel today. The difference is hardly critical, but it still causes some die-hard .30-06
fans to cry foul. They are dumbing down their favorite cartridge by saddling
it with a 22-inch barrel. The real question is whether any big game animal is going to
detect the difference - or whether the bullets will bounce off if the velocity is a
smidgen slower.
And there is at least one more
factor to consider - statistics.
There was a time when folks like
Speer, Hornady or Lyman published loads without too much concern for statistical averages.
As such, they may have worked a bit closer to the maximum allowable pressure limits for
any given cartridge. Nowadays, however, they fire at least 10 shots, determine the
standard deviation, then calculate ±3 SD to find out if 97 percent of all shots (based on
the sample) will not exceed the maximum allowable pressure.
For example, if the average pressure
for 10 shots is 55,000 psi with an SD of 2,000 psi, we have a minimum and maximum of
49,000 and 61,000 psi, respectively. But the maximum allowable for the cartridge of
interest is 60,000. So, the load is reduced somewhat to bring the average pressure down
and to prevent any one shot from exceeding the SAAMI limit. So instead of an average
operating pressure for any given load at 60,000 psi, the necessary average, dependent on
an SD of 2,000 psi is somewhat less than 55,000 psi. You can bet your sweet whatever that
Ned Roberts, Phil Sharpe or Townsend Whelen werent subjecting every load to
statistical analysis - they didnt even have a chronograph in most cases and simply
estimated velocity and pressures.
At any rate, you get the drift. Hunters
demands for more stream- lined bullet designs that are tough enough to bust through the
engine block of an S-10 and carry through the atmosphere with less than 4 inches of drop
out to infinity have brought us the Swift Scirocco, Nosler Ballistic Tip and Partition,
Winchester Fail Safe, Barnes X-Bullet, Speer Grand Slam, Hornady SST, etc., etc., etc.
Thats not all that bad, in spite of the naysayers who scream foul when some outfit
publishes a load that cuts 75 fps off their pet load.
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