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It seems as
though everybody has their own idea of what the perfect cast bullet should look
like (I know that I certainly do!). You might think that custom mould makers
would be rolling in business to answer this market need, but the traditional
cherry-based method of making bullet moulds is both costly and time consuming,
and only allows bullets of one diameter to be produced from a given cherry. The
relatively high cost of this process tends to dampen the enthusiasm of many
would-be mould designers. Modern CNC machining methods allow the operator to
lathe bore most any mould design that can be captured in a CAD file. All this
then requires that the bullet design be reduced to the appropriate series of
dimensions, angles, arcs, etc. Modifications to a given design only require a
few keystrokes at a computer, instead of machining a completely new cherry. Dan
at Mountain Molds has made capturing this information very easy with his
calculation spreadsheet and drawing program. I recommend that you go to his
website:
http://www.mountainmolds.com and play with his software
to see how easy (and how fun) this is. The ease of this process allows you to
run through several design iterations and quickly refine your design to optimize
those features that you want to capture, or to take an existing design and
tailor the bullet diameter to fit your particular gun. Once you have the bullet
you want, you simply click on a button to place the order. He plugs your numbers
into his CNC and your mould comes out the other end and is shipped to your door.
Custom-made 2-cavity bullet moulds for $75 are hard to ignore!
I like lots
of lube, lots of bearing surface and lots of meplat. I tend to lean towards a
Keith-style lube groove(s) -- wide, flat-bottomed, and with beveled edges.
Concurrently, I like wide driving bands to allow the lands to “bite” the bullet
more firmly. Best bullet alignment is obtained with those bullets that have
bearing surface over at least half of their length. Review of the accurate
bullet designs that exhibit long range stability and don't tend to tumble on
impact and penetrate in straight lines (Keith SWC's, SSK FP's, LBT LFN, etc.)
reveals meplats of 65-75% of bullet diameter. Larger meplats lead to bullets
that have marginal stability and can tumble on impact (wadcutters, some WFN's,
etc.). This observation has led me to adopt a 73% meplat as my approximation of
ideal (nose length and ogive radius also factor into this, but that's a separate
discussion). So those are the basic design concepts that led me to design these
moulds. You may have different ideas that you can incorporate into your mould
designs just as easily as I did mine.
Dan offers
moulds made in both aluminum and brass, so I bought 2 of each in order to
compare and contrast. Dan's basic mould design changed after I ordered the first
mould, to include a 3rd alignment pin (for more positive alignment), and to use
3/16" 4140 steel for the sprue plate, instead of the tool steel that had been
used previously. The new sprue plate design has the striker plate at the 12
o'clock position instead of the 3 o'clock position. He has also cut the sprue
plates so the back side of the striker plate is cut at a 45 degree angle, which
saves material (holding costs down), but it also makes closing the sprue plate
after dumping bullets a smooth, sliding motion rather than a striking motion, a
change that I like very much and one that should add to mould longevity. The
first mould I ordered from him took 3 weeks to arrive, the second order of 3
moulds took 4 weeks to get here. Outstanding turnaround for custom work! The
workmanship displayed in all 4 moulds is excellent.
The 4
moulds I had Mountain Molds (his spelling, not mine...) make for me were:
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> A .404” 200 grain Keith-style
SWC, designed for the Herter’s .401 Powermag revolver |
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> A .312” 100 grain Keith-style
SWC for the .32 H&G Magnum |
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> A.412” 300 grain GC-FP for the
.405 Winchester |
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> A .453” 325 grain FP for the .45 Colt
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All of these
bullets were designed as hunting bullets, have meplats that are 73% of bullet
diameter and the 3 revolvers bullets have deeply cut beveled crimp grooves. I
did not have a crimp groove put on the .405 Winchester bullet as I will be using
this in a single-shot and therefore don’t need a crimp.
The
Keith-style SWC bullet designed for .401 Herter's Powermag dropped from the
blocks at .404" and weighed 199 grains when cast of WW alloy sweetened with 1-2%
tin. This is exactly the diameter I wanted for this bullet as the Herter's
(Hawes) revolver has .405" throats and a groove diameter of .403".
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Figure 1: .40
caliber Keith-style SWC for the Herter's .401 Powermag made by
Mountain Molds. |
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Bullets were "sized" .405"
and lubed with homemade moly lube (equal parts by weight beeswax and Sta-Lube
Extreme Pressure Moly-Graf grease). The bullets were round (i.e. diameter didn't
vary from point to point, a common problem with mass-produced bullet moulds),
and dropped from the cavities smoothly and easily. This bullet has provided
the best accuracy of the 10 or so bullets tried in this revolver to date. The
best load tried so far is 18.0 grains of Accurate Arms #9 with a CCI 350 primer
for 1405 fps, with 5 shots going in to about 2" at 25 yards (6 1/2" barrel).
The meplat diameter on
this bullet is .295", which is actually larger than that found on the highly
respected .44 Keith SWC (Lyman/Ideal 429421, meplat diameter .275"). Since it is
the meplat that is responsible for creating the wound channel, I anticipate this
bullet should do just fine on deer sized game, and I intend to hunt with it this
fall. As for larger sized game, I would prefer a heavier bullet (from a
revolver).
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Figure
2: .32 caliber
Keith-style SWC for the .32 H&R Magnum made by Mountain Molds. |
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The
Keith-style SWC designed for the .32 H&R Magnum was also nice and round, and
also fell from the blocks with ease. Bullets were .313" in diameter and weighed
101 grains when cast with WW alloy. Again, this is just the diameter that I
wanted, and an excellent fit for my .32s. Sized .312" and lubed as above, and
loaded into .32 H&R Mag cases over 6.5 grains of Accurate Arms #7 and a CCI 550
primer grouped 5 shots into 1 1/8" at 25 yards. Velocity was 1174 fps from the
6" S&W Model 16 .32 H&R Mag. This is a very clean load, and is ideally suited to
small game and vermin.
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Figure
3: 300 grain
GC-FP bullet for the .405 Winchester made by Mountain Molds. |
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I have a 14" Contender barrel
that started off life as a .41 Magnum. It has a .411" groove
diameter and was re-chambered to .405 Winchester. When fired from a
Contender, the .405 Winchester must be kept at or below about 42,000
psi peak pressure to keep back-thrust within the capabilities of the
Contender's frame. "Load From a Disc" calculations suggest that this
is possible by keeping velocities with 300 grain bullets below 2000
fps with powders slower than the IMR 3031 and H335 class. The
flat-point bullet that I designed for the .405 Winchester was put
together explicitly for this gun. Previous work with 370 grain cast
bullets at 1700 fps revealed that recoil was, shall we say "brisk",
and trajectories were somewhat curvaceous. The standard weight for
the .405 Winchester is 300 grains and I wanted a useful hunting
bullet of this weight both to flatten trajectory and to reduce
recoil (relative to the 370s that I had been using). Since it's a
single shot, there is no need for a crimp groove, so I didn't ask
for one (besides, that gives me that much more bullet metal for
positive engagement with the lands). It has 2 wide, flat grease
grooves, and a GC shank cut for Hornady .416 GC's. These bullets
drop from the blocks at .412" diameter and weigh 290 grains when
cast of water-quenched WW alloy. Adding a GC and lube raises their
weight up to 298 grains; exactly what I was looking for. When seated
on top of 55.0 grains of H4895 and sparked with a Fed 215, this
bullet delivers 1929 fps and is very accurate. This combination is
remarkably flat-shooting, and now constitutes my preferred load for
this gun.
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Figure
4: 325 grain
PB-FP mould for the .45 Colt made by Mountain Molds. |
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The fourth
mould I asked Dan to make for me was for the .45 Colt. I have a Ruger Super
Blackhawk that I converted to .45 Colt with .480" chambers and .452" throats,
and I wanted a 325 grain plain-based bullet with a 73% meplat specifically for
this gun. This 2-cavity brass moulds drops bullets that weigh 325 grains and
measure .453-.454" in diameter when filled with WW alloy. Sized .452" and loaded
on top of 21.3 grains of H110 with a CCI 350 primer, this bullet delivers 1227
fps and good accuracy from the 7 1/2" Ruger. With a .330" meplat and 325 grains
of bullet weight this promises to be an excellent hunting bullet! It is my
intention to introduce a large pig to one (or more) of these bullets this fall.
I'll let you know if he's impressed.
The two
Keith-style SWC moulds were cut from aluminum, while the 2 ogival flat-point
moulds were cut from brass. The surface finish of the brass moulds is
beautiful. The aluminum moulds show more tooling marks than do the brass moulds
(which one would expect, that's just the basic nature of the two different
metals), but the cavities on all 4 are well cut and release their bullets easily
and smoothly. Bullet finish in all cases is smooth. I couldn't tell any
significant difference in terms of how long it took moulds cut of each metal to
warm up (that's more a function of how much molten metal one is pouring into the
mould blocks, besides I pre-warm my moulds as I'm melting the alloy). Overall,
these Mountain Molds drop some of the roundest bullets that I've ever cast, and
they deliver bullets that were either spot on, or very close to the target
diameter. In summary, Dan makes exactly what you order, his moulds produce
bullets that are round and the right size, and his turn-around time and prices
are quite good.
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