From: [EMAIL PROTECTED]
Reference the posting from Alex Hamilton: Yes, I am well
aware of the points he made with regard to bullet sizing
and hardness and am in full agreement with him.
When I first experienced leading problems with my S&W
686 I recognised that there were several possible
causes: The gun, the bullets, the powder, the primers(?),
my reloading techniques, some combination of the above.
I decided that I could eliminate the gun from the
equation because it performed very well with factory 38
Special wadcutter ammunition. That left the bullets, the
powder and the rest.
I tried various bullets, aiming always to use bullets
that were as close as possible dimensionally to the
chamber throats of my gun. I tried hard bullets and soft
ones - bearing in mind that I was trying to produce a
target load of nominally 148grs/770 ft/sec or
thereabouts - which is supposed to be an 'optimum'
velocity for these projectiles for target purposes. I got
very good results from the accuracy and velocity
consistency criteria but, with N310 powder, got heavy
leading with soft lead GECO bullets. I tried different
amounts of neck tension - by neck sizing to various
diameters. I tried crimp and no-crimp and various
seating depths for the bullets, - all to no avail.
The leading problems that I experienced with N310
powder and 38 Special cases were just as serious with
357 Magnum cases - I tried these to see if reducing
the bullet jump from case to chamber throat would
improve things. My chosen load for the Magnum cases
was 3.5 grains of N310 behind the GECO bullets and
this gave about 800 - 830 ft/sec. There was very
little to choose in accuracy between the two
loadings - I shot my best ever group with the 357
load (a sad story of 'almost but not quite' as I
'lost my bottle' on the last shot and threw it wide
into the 7 ring, thereby reducing my score to 95 on
a PL12 at 20 yards. Otherwise it could have been a
three hole ten shot group scoring 98 - first shot
being an 8. All ten shots were exactly right for
elevation and were fired one handedly from a standing
position i.e standard off-hand target shooting.) The
load was accurate enough. The problem, as usual, was
me! This card was not entirely a 'one off' as I had
many other cards with good groups - I must admit to
quite a few that were not so good too but, in my
vanity, I only kept those that were 'statistically
viable' i.e. the good ones!
I had no problems with leading in 38 Special cases
with 158 grain Round nose swaged 'Silvalube' bullets
( 3.9 grains N310, very nice, consistently accurate
load, about 800/850 ft/sec.out of my gun, 2.5 inch
10 shot groups at 25 metres fired off-hand.) These
bullets were sized .357, as were the hollow based
GECO's I used in my so-called target loads. Silvalube
hollow based wadcutters were, in my experience, less
satisfactory from an accuracy point of view but
leaded a bit less than the GECO's. I chose not to
use them for my target loads. The GECO bullets were
very soft lead and should have 'upset' quite easily,
even with my relatively mild loads. I noticed the
same leading problems in a S&W 586 that belonged to
a colleague of mine. His gun had, if anything,
slightly tighter chamber throat bores than my 686
and was a superior piece of construction generally.
My 686 measured - only by using internal calipers
and an external micrometer, I'm afraid and so one
would have to trust my 'feel' for these instruments
- measured a 'full' .357 inches i.e. it was probably
nearer .358/3585 (all six chambers were remarkably
consistent, though) but the GECO bullets would not
have had to upset much to fill the chamber throats.
As I said, these bullets were very soft lead, coated
with some sort of grease lubricant. They were a loose
sliding, but not rattling, fit in the chamber throats
before they were seated in the cases. I had been
wondering if the bullets had actually been too soft
as the route from cartridge case to barrel forcing
cone is quite a rough ride, especially for a
hollow-based bullet with a relatively thin skirt wall
and from a 38 Special case length. As I had no
problems at all with factory Winchester 148 grain 38
Special wadcutter ammunition I concluded that there
was nothing wrong with my revolver either in terms of
its dimensions or surface roughness of the chamber
throats and barrel forcing cone but that the problems
must lie elsewhere.
I had less leading with N320 powder but couldn't
quite get the accuracy that I achieved with N310 in
my 357. It was excellent in my 45ACP, though. I
eventually fell back on Hercules 'Bullseye' in the
357 which gave excellent results with the bullets
that I had! The dirt that Bullseye caused was easily
wiped off with a few cleaning patches, the leading
with just a few strokes with a phosphor bronze
bristle brush and the ubiquitous Hoppes No.9 or
Parker Hale version thereof. With N310 I was in for
a major scrubbing out exercise with the bronze
brushes. I even built a jig to hold the cylinder to
make the scrubbing easier.
I would be interested in other people's experiences
with these powders as I still have some of the N 300
series (310, 320, 340) N310 is rated as a little
'faster burning' than Bullseye by Vihtavuori, N320
about on a par with Red Dot and N340 somewhere
between Herco and Blue Dot. N310 has about the same
burning rate as ICI's NGSP78 or Hodgdon's HP38, ie
very fast burning indeed.
By the way, 3N37 was introduced relatively recently
to the V/V range, probably about 5 - 6 years ago.
I hope to receive some further advice that may help
me to solve this leading problem.
Yours sincerely,
Richard Malbon
--
So I can remember the name of a powder I've never used
that I was given a sample of six years ago but I cannot
recognize the stuff when I see it in a shop. Hmm.
Steve.
Cybershooters website: http://www.cybershooters.org
List admin: [EMAIL PROTECTED]
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