I have been doing a tremendous amount of load development
with the new .500 S&W Magnum. One shooting enthusiast named Casey on a gun board
asked me to back up and offer any insight I might have on the .44, as he did not
see a .500 in his future. He wanted to know if there was anything to add to the
information found in the typical loading manual, or the gun magazine that
referred to "time tested Keith loads." He wanted to know about best and worst
powders, bullets, alloys, etc. Here is what I told him:
Casey, you are right, you can do a lot better than just
repeating the mantra of "22 2400 250 Keith."
Here are some observations that I've had while working with
the .44. Many are applicable to other calibers.
Worst powders: I don't like light charges of fast
powders in any cartridge. In general, I like using the slowest powder that will
give the desired velocity. You cannot get a dangerous overload with this
practice. Leading is less likely, for reasons I'll explain later.
The single best
powder for full .44 loads is WW296/H110 or other surplus equivalent. This ball
powder was designed for the .30 Carbine and magnum handgunners have adopted it
with good reason. Of the over 100,000 .44 Mag loads I have fired, over 80% of
them have been 25 H110/296 and a 250 Keith, the Hensley & Gibbs #503. This
bullet goes out to the front of a S&W cylinder. 25 grains of this powder might
be too hot for a "Keith Style" bullet with a shorter nose and more shank in the
case, or a jacketed slug. My load goes 38,500 CUP in the Super Vel pressure gun.
While the Keith bullet is accurate, it is not the MOST
accurate .44 cast bullet style. I use it because it is accurate and I have
8-cavity H&G gang molds for it. H&G went out of business before I got heavily
into mold design. If I were going to shoot a cast bullet in the .44 for absolute
best accuracy, I would make it a design with a bore riding nose section, an
ogival or truncated cone nose, and multiple thin grease grooves. (We have better
lube than we did 70 years ago.) I'd put the crimp groove where it would give an
overall length as long as possible for the gun I was loading for (.44 mags are
not all the same cylinder length.) The JD Jones SSK designs are good examples of
the kind of bullet I'm describing. They shoot about 25% tighter on average than
Keiths in my guns, about 3 to 4 MOA vs 4 to 5.
You do not need gas checks in the .44 (or any other revolver)
unless you are trying to correct a condition and you aren't willing to actually
address the root cause of the problem.
Leading is most
often caused by gas cutting. Gas cutting happens when your bullet is smaller
than your chamber throat (front of the cylinder or the throat section in a
rifle.) When the round is fired, hot gas gets around the bullet as it exits the
case and enters the throat and bore, ruining the desired gas seal and causing
leading, especially at the back of the barrel. Sometimes, leading will be made
WORSE by going to a harder bullet (since it won't deform at all) and may be
actually be IMPROVED by a softer alloy that "slugs up" and seals off the gas. I
don't shoot the super-hard alloys in revolvers; most revolver loads don't
generate enough pressure to slug up the bullet.
However, IF you like faster powders, you may get leading and
think you need a harder alloy, which may or may not cure the problem. This often
happens with loads like 10 grains Unique for 1000 FPS. It can lead badly,
because (I believe) of the fast pressure spike of the expanding gas ball in the
half-filled case hitting the base of the bullet. Before changing the alloy,
change the powder. Try 25-28 grains WC680 for 1150-1250. This much slower powder
fills the case entirely and the pressure builds more slowly. Leading will
disappear, unless something is REALLY wrong.
I never tried H335, BLC-2, etc, in the .44 because I prefer
full loads in that caliber. In the 500, you get almost 1400 FPS with a case full
of these rifle powders and a 450 grain bullet. Although this is 400 FPS below
maximum, a 450 @ 1360 (or even less) still might be all you want.
I recall a Du Pont manual from around 1975 (8 1/2 x 11, 20
pages, paper, brown cover, tan pages, mostly shotshell data) that listed loads
for ALL their IMR powders in various metallic cartridges, like 4350 and 4831 in
the .44 Magnum. Peak pressure with a full case was something like 14,000 CUP
IIRC. This was VERY interesting.
If you want a 900
FPS .44 load (I don't) and have a chronograph, try loads at 100+% loading
density using WC680 and slower powders, like Accurate 2015, H322, and H335. Pick
dense powders like the ones above. If the load is uniform and of the velocity
you want, try it on paper. Uniform loads tend to be accurate ones.
BTW bevel-base cast bullet designs are much-loved by
commercial outfits for the ease with which they go through automated
lubricators, and reloaders like the ease with which they enter case necks, but
they make gas cutting WORSE for obvious reasons. I avoid them.
Find a machinist with a set of plug gages or better yet buy a
complete set .251"-.500" (250 gages) for $85 or so from a machine tool supplier.
Buy a micrometer while you're at it.
Measure your chamber throats. They probably go at least .431"
and maybe .432". You need bullets that are no more than 1/2 thousandth smaller
than your chamber throat. Ideally you want a bullet sized such that you can push
it through your tightest throat with moderate finger pressure.
With some guns and certain loads you can shoot pure lead
un-lubricated bullets without leading IF they are the right size.
If you shoot commercially cast bullets you're limited to your
choices. Try to find a supplier that can provide you with .431" (or whatever)
sized bullets in a non-bevel-based style.
Failing that, buy some NECO P-wads. These are .065" PVC discs
you put in the case before you insert the bullet. Buy them for about $7 a
thousand. I make my own with a .432" hand punch and sheet PVC for $2/thousand.
P-wads form a gas seal and are effective to some extent at reducing gas cutting
with undersized bullets. So are slower powders, as mentioned above.
I measured the
throats of two 329s and a .428" gage was the largest that would enter. Same with
a PC 629 7 1/2" slab side, the one with Mag-na-ports (I think it's called the
"Magnum Hunter".) ALL my old Model 29 throats go .431"-.432". The new guns are
tighter.
Heavy loads with the ball powders need high neck tension and
heavy crimp. Polish down the expander plug until it does not expand the neck AT
ALL after sizing. Adjust it so that the case mouth is belled just enough to
start the bullet in the case and no more. This keeps the brass from being
overworked. Use a heavy crimp. You may need to try different make crimp dies to
find a good one. I use Star dies, so that doesn't help you. My loads in the .44
NEVER pull, not even 320s @ 1225 in a 329.
There are only two problems with H110/296, neither of which I
have experienced:
1. Less-than-full charges may leave a bullet
in the barrel. Don't load too low, like 19 grains. If you want less velocity,
use a full charge of a slower powder, like WC680 (Accurate 1680.)
2. Erratic results in VERY cold weather. If
you regularly shoot in such conditions (I don't), Blue Dot is the powder you
want, from what I've read of others' experiments.
Hope this helps.
John Ross 9/10/2003
Copyright 2007 by John
Ross. Electronic reproduction of this article freely permitted provided it is
reproduced in its entirety with attribution given.
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