Product: |
550/650 Toolhead Clamp Kit |
Manufacturer: |
UniqueTek |
Reviewed By: |
ArmsVault |
Date of Review: |
Aug 08 |
UniqueTek
550/650 Toolhead Clamp Kit
July 2008
UniqueTek, of Gilbert, AZ, is a firm
specializing in producing innovative
reloading products. Most of their product
offerings are geared toward reloaders who
use Dillon Precision reloading equipment.
Specifically, UniqueTek’s products are meant
to enhance both the precision of loaded
rounds and/or the speed of production using
Dillon’s already excellent equipment.
UniqueTek’s Chief Technology Officer (CTO),
Lee Love, recently sent over a sample of one
of their up and coming new products designed
to enhance the Dillon 550/650 series of
presses.
The product in question is UniqueTek’s
550/650 Toolhead Clamp Kit. Conceptually,
the toolhead clamp kit is designed to “lock
down” a toolhead in the Dillon 550/650 line
of presses. According to Lee the thinking
behind the toolhead clamp kit originated
from the standard Dillon press and toolhead
for the 550/650 series having relatively
loose tolerances due to the manner in which
both the toolhead and the press toolhead
slot are machined, as well as the use of the
stock drop-in pins to secure the tool head
in the press. In a nutshell, Lee believes
that, combined, the effect of the play
between these two parts can cause
appreciable variation in loaded cartridge
overall length (OAL) due to the toolhead
moving vertically and/or horizontally when
the shellplate fully inserts cartridge cases
into the toolhead’s dies at the top of the
press stroke. This is not to say that the
design of the standard Dillon 550/650 series
toolhead and press is any way flawed, just
that by their manufacturing tolerances they
can contribute to OAL dimensional variation
in reloaded cartridges. Likely this
variation will be negligible, or have
negligible effect on the performance of
reloaded rounds. However, in the case of
modern high-pressure cartridges,
particularly certain handgun cartridges
which seek to combine smaller case sizes
with major caliber bullet velocities and
energy levels, OAL variation needs to be
minimized for safety’s sake. |
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Take for instance the 9mm round or the
relatively newer auto pistol cartridges such
as the .40 S&W and the .357 SIG. Each of
these mid-caliber cartridges is designed to
extract major caliber bullet velocities and
energy levels from their relatively small
volumetric cases. The benefits of marrying
together major caliber performance with
small cartridge size is readily apparent in
these rounds being widely utilized by U.S.
law enforcement agencies. These agencies
lead the way in fielding semi-automatic
sidearms which seek to strike the optimum
balance between cartridge “horsepower”, high
magazine capacity and relatively modest
handgun size. Given the small internal
capacities of these cartridge cases and the
powder charges needed to drive their modern
JHP bullets at high velocities, the
pressures they generate are by and large at
the higher end of the scale. As reloaders
know, consistently controlling bullet
seating depth, especially in small
volumetric cases such as these, is crucial
in order to keep reloaded rounds within safe
pressure limits. A bullet seated too deep
could likely cause a dangerous overpressure
situation. UniqueTek’s toolhead clamp kit is
designed to minimize this occurrence by
rigidly holding a Dillon’s toolhead in
place, and thus eliminating any possible
vertical movement of the toolhead assembly
as cartridge cases on the shellplate are
being ran up into the dies. Any vertical
movement of the toolhead assembly will
likely cause OAL and crimp dimensional
variations in reloaded rounds. |
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UniqueTek’s kit provides hardware and
detailed instructions with which to modify a
stock Dillon toolhead and convert it from
being held in place with the Dillon stock
drop-in pins, to being rigidly secured with
threaded screws. ***NOTE*** THIS
MODIFICATION DOES NOT REQUIRE THAT THE PRESS
FRAME OR THE PRESS TOOLHEAD SLOT BE MODIFIED
IN ANY WAY. Modification is made solely to
the pin holes of the toolhead.
Briefly, the process for toolhead
modification is as follows. A stock aluminum
Dillon toolhead has the retention pin holes
on its flanges drilled out with the supplied
9/64th” drill bit. The top of these newly
drilled holes are very lightly chamfered
with a ¼” drill bit. Once this is done a
hand powered 5-40 tap is used to cut threads
in the holes. Plenty of patience, a steady
hand and liberal use of cutting oil are
required so as to perform this step properly
and not break off the tap in the soft
aluminum material. After the threads are cut
and the holes are blown out of all debris,
stainless steel “helicoil” liners are then
installed in the threaded holes with a
supplied handheld tool. These stainless
steel helicoils are of a harder material
than the aluminum toolhead and act as a
“sleeve” which the hex head screws will lock
up with a bit later on. To those familiar
with reworking automobile engine heads, you
will probably recognize the concept behind
the use of helicoils for this application.
If not for the helicoils, the act of
repeatedly screwing and unscrewing the steel
retention screws as the toolhead is
installed/removed from the frame would strip
the threads in the soft aluminum toolhead.
After the helicoils are in place the
modified toolhead is reinstalled in the
press along with the appropriate dies and
power measure assembly, the user lightly
threads the supplied hex head screws and
spring washers from the kit into the
toolhead via the retention pin holes in the
press. Once each of the dies are re-adjusted
and each one has a case ran up in them, and
with the press ram at the top of the stroke
exerting maximum pressure on the toolhead
assembly, the screws are then tightened down
firmly with the supplied hex head wrench.
This “locks” the toolhead into position at
the press’s maximum mechanical pressure on
the toolhead. To remove the toolhead in
order to change over to another caliber, all
the user has to do is unscrew the hex head
screws and slide the toolhead out of its
slot. Again, the press retention pin holes
are not altered in any way. The hex head
screws drop through these holes and screw
into the modified toolhead’s helicoil-lined
threaded holes. The UniqueTek Dillon 550/650
Toolhead Clamp Kit tested contained enough
helicoils to modify six separate Dillon
toolheads.
In practice, the modification of the
toolhead pin holes and the installation of
the helicoil sleeves proved to be somewhat
of an involved and lengthy process. It is
highly recommended that the user read the
directions thoroughly in addition to
obtaining the recommended wet and dry
lubricants needed to properly bore and tap
the holes in the toolhead. Additionally, I
would recommend that the user have access to
a drill press. Although UniqueTek’s
instructions do not specifically call for
boring out the toolhead pin holes with a
drill press it is paramount that these holes
be bored out absolutely vertical so that the
subsequent thread tapping and installation
of the helicoil inserts is performed
properly, as well as to ensure that the
threaded retention screws can be
subsequently screwed in and out smoothly
without binding. With Dillon toolheads
running about $20 a pop at retail, why risk
ruining one when trying to bore to the holes
freehand with a hand drill? Once the 9/64th”
holes have been successfully bored out, the
process of cutting the threads is done
manually with the supplied tap. The user
needs to supply a handle for the tap as well
as thread-cutting lubricant. UniqueTek
offers an optional tap handle for
approximately $3.00. Again, a steady hand
and consistent pressure are required so that
the threads are cut consistent with the
vertical axis of the bored holes so as to
eliminate cross-thread issues when
installing the helicoils and threaded
screws. After completing this step and
cleaning out the threaded holes, the
installation of the helicoils took a couple
of attempts before they seated properly. The
first attempt to seat them was unsuccessful
with the helicoils not seating all the way
down into the threaded holes due to the
supplied helicoil installation tool losing
proper purchase on the coils as I tried to
screw them in (Lee Love advises that he’s
subsequently redesigned the helicoil
insertion tool to ensure that it maintains
solid purchase on the helicoils). On the
second attempt I was able to finally get
them properly seated. Once the coils were
installed the modified toolhead was ready to
have the dies reseated and then the whole
assembly reinstalled in the press. At this
point the threaded hex head screws were
dropped down through the press’s retention
pin holes and screwed in slightly. They were
not tightened down at this point. Four
cartridge casings were progressively indexed
through the loading cycle and only then,
after each die had a case inserted and the
shellplate was at the top of the stroke,
were the retention screws tightened down
hand tight. |
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For the purposes of evaluating the toolhead
clamp kit I decided to measure the
pre-and-post modification OAL for 9mm
reloads to determine the extent to which the
modification minimized or eliminated
dimensional variances. I selected fifty
once-fired, clean Remington-Peters
headstamped cases from my 9mm brass bucket.
I inspected each case prior to trimming them
to the Speer manual’s recommended
trim-to-length of 0.744”. I then chamfered
the case mouths. By way of bullets, I used
Speer Gold Dot 115 gr. JHPs to reload the
cases with. I reloaded twenty-five rounds as
I normally would with the stock unmodified
Dillon toolhead setup. I sat aside the 1st
through 4th rounds as well as the 22nd
through 25th rounds loaded. Out of the
remaining batch of seventeen rounds from the
lot, I had a friend randomly select ten
rounds for measurement. The reason I didn’t
include the first four or the last four
rounds from this lot of reloads is because I
wanted to measure only rounds that were
produced when all die stations were fully
engaged and consistent ram pressure was
being applied to the toolhead via the
shellplate. The results are as follows: |
Pre Toolhead Clamp Kit |
Round # |
OAL (in.) |
|
|
1 |
1.083 |
|
|
2 |
1.086 |
|
|
3 |
1.084 |
|
|
4 |
1.085 |
|
|
5 |
1.085 |
|
|
6 |
1.085 |
|
|
7 |
1.085 |
|
|
8 |
1.087 |
|
|
9 |
1.084 |
|
|
10 |
1.088 |
|
|
|
|
|
|
Min. |
1.083 |
|
|
Max. |
1.088 |
|
|
Range |
0.005 |
|
|
Mean |
1.0852 |
|
|
Median |
1.085 |
|
|
STD
(n) |
0.0014 |
|
|
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At this
point the toolhead was taken out of the
press and the dies removed. As per the
discussion above the UniqueTek Toolhead
Clamp Kit was then installed and the
modified toolhead reassembled and
reinstalled back in the press. After
getting the dies readjusted, I again loaded
a batch of twenty-five rounds exactly as I
had the first batch of twenty-five. Again I
had my friend select ten rounds randomly
from cartridge numbers 5 through 21 out of
this lot as well. These ten randomly
selected rounds were then measured. The
results are as follows: |
Post Toolhead Clamp Kit |
Round # |
OAL (in.) |
|
1 |
1.085 |
|
2 |
1.084 |
|
3 |
1.085 |
|
4 |
1.085 |
|
5 |
1.083 |
|
6 |
1.086 |
|
7 |
1.085 |
|
8 |
1.083 |
|
9 |
1.085 |
|
10 |
1.085 |
|
|
|
|
Min. |
1.083 |
|
Max. |
1.086 |
|
Range |
0.003 |
|
Mean |
1.0846 |
|
Median |
1.085 |
|
STD
(n) |
0.0009 |
|
|
OAL Comparison Results |
|
Pre |
Post |
Difference |
Min. |
1.083 |
1.083 |
0 |
Max. |
1.088 |
1.086 |
0.002 |
Range |
0.005 |
0.003 |
0.002 |
Mean |
1.0852 |
1.0846 |
0.0006 |
Median |
1.085 |
1.085 |
0 |
STD
(n) |
0.0014 |
0.0009 |
0.0005 |
|
By way of OAL, the variation between the
randomly selected pre-and-post lots was
measureable. An improvement of 0.002” in the
OAL statistical range was recorded. Overall,
the spread tightened up by 0.002” as well.
Lee Love indicated that customers usually
see total OAL ranges of no more than 0.001”
to 0.003” with the toolhead clamped, so in
this regard I am of the opinion that my
results are consistent with the experiences
of other users.
From a theoretical standpoint I can
certainly see where this type of
modification has merit, as it is always
advantageous to rigidly control dimensional
precision and consistency in reloaded
rounds. Does the average reloader absolutely
need it though? At the risk of equivocating
here: It depends. If I were progressively
loading any of the higher velocity/smaller
case volume cartridges such as the 9mm, .40
S&W, .357 SIG, etc… I would certainly modify
my toolheads with the kit in order to
minimize OAL variation. Similarly, if my
goal is to progressively load high
performance self defense/hunting rounds or
match grade accuracy benchrest-type rounds I
would benefit from the use this product in
order to extract greater precision and
performance from my loads – even if I’m
using expensive “benchrest dies” – as these
are moving vertically in the unmodified
toolhead with every pull of the lever the
same as standard type dies. On the other
hand, if I were progressively loading
mid-range loads for many of the relatively
low pressure/larger volume cartridge cases
such as the .45 ACP, or many of the
straight-walled revolver cartridges, I
probably wouldn’t bother with the
modification due to pressures in these
cartridges not being as impacted by modest
OAL variations.
The average user should be mindful that
there is some effort required to
successfully perform these modifications.
For those who are interested, but not
mechanically inclined, I would recommend
that they contact a local machine shop in
their area, or any of their buddies who have
might have good mechanical aptitude, for
assistance in installing the kit properly on
their toolheads so as not to ruin any. As an
option, UniqueTek offers for sale OEM Dillon
550 and 650 toolheads with their Toolhead
Clamp Kit parts pre-installed. UniqueTek is
currently conducting market research to
gauge the market for offering Toolhead Clamp
Kit installation services on
customer-supplied toolheads.
This product is but one of the many
interesting and innovative products which
UniqueTek offers reloaders and shooters. You
can check out their 550/650 Toolhead Clamp
Kit, as well as toolheads with the clamp kit
pre-installed, at their excellent website:
www.UniqueTek.com or you can reach
UniqueTek’s customer service and technical
staff at their corporate offices in Gilbert,
AZ at: (480) 216-2041. UniqueTek proudly
produces this product here in the U.S.A. |
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