As many hobby casters know,
manually sizing projectiles can be at times, difficult and labour intensive. The required force to
push a projectile through a sizing die will vary, this will depend projectile
style, alloy hardness, whether the projectile is bare lead or coated and or
lubricated. Extent of diameter reduction needed and the style of the sizing die
(short or long sizing bearing surface).
To overcome excessive forces and
binding of projectiles in a sizing die, casters both hobby and commercial have
tried all types of coatings and lubricating products with varying success.
Whilst providing some reductions in required sizing forces there have been
problems with residue and contamination on the sized projectiles. Some of which
are noticeable when handling the projectiles during loading or increased smoke
when fired. Also waxy, or thick lubrication will gum up loading dies over time
and the dies will require regular cleaning.
I was looking for a better more
superior purpose designed product for projectile coating and came across Hi-Tek
Super Coat. Straight away I noticed sizing became much easier, dies and
equipment stayed clean, and I no longer needed to lube the coated projectiles
to manual hand size.
As production increased and I started to produce projectiles for a few friends, I needed a way to automate sizing. The first automated sizer I built was slightly under powered and it was discovered lubrication of the projectiles was needed for the machine to cycle. After trying a few different products, I was concerned about residue on the projectiles and contamination. I thought there must be a better option out there.
Thinking about it, it was
obvious I should contact the person who developed Hi-Tek Supercoat. I
contacted Joe at J and M Specialized Products and was informed there was a
product called Aqualube. It was designed to aid sizing and would not
contaminate equipment.
A small bottle was purchased and the Aqualube was supplied to me as a concentrate. I Mixed 15ml concentrate to 1000ml of denatured alcohol. Used a spray bottle to apply and then gave the bucket a shake. A little goes a long way.
I tried the automated sizer again and I was truly amazed just how much of a difference Aqualube made. The automated sizer that was underpowered and struggling to size some projectiles, now was motoring along without a problem. You could even hear a difference in the machine.
Later, a couple of questions
arose. How well does Aqualube work? Is it possible to measure the affects?
Well, I know Aqualube works for
its intended purpose and, anyone who has used it will understand this however,
I had nothing other than personal experience to say so. Joe knew his product
performed well but when asked, he was not able to provide any specific data.
After discussing this with Joe,
Joes asked if it was possible to devise a way to measure the effects of
Aqualube and whether I was willing to conduct independent tests and provide
data on my findings. Of course, I said yes because I found the idea to be an
interesting challenge.
We spoke about ideas and came up
with a simple yet effective device. The setup includes a single stage press
with a load cell mounted to the ram. With this configuration I could measure
directly between the cell and die. The press stroke length had to be modified
to account for the space occupied by the load cell.
The data was captured using a
load cell meter connected to a laptop computer. Data was then converted into a
graph that indicates peak force.
My first tests worked extremely well, better than expected. There was a huge difference in forces required to size uncoated, Hi-Tek coated and Hi-Tek coated with Aqualube applied however, I encountered one problem. I underestimated the force that was needed to size a projectile and the load cell maximum force of 150kg was exceed when trying to size uncoated projectiles.
A larger load cell was purchased that has a maximum of 375kg. More tests were completed, and I was able to obtain useful data showed consistent results. Aqualube provides huge
reductions with required sizing force.
Tests have been completed using two different style projectiles and each style exhibits similar data. 136 grain Button Nose Wadcutter and 122 grain Flat Point. Each style was tested uncoated bare lead, coated with Hi-Tek Supercoat and Coated with Hi-Tek Supercoat and Aqualube applied. 50 projectiles for each test. All projectiles were cast using the same batch of certified 92-6-2 lead alloy.
Whilst figures shown in the
graphs are in kilograms, the unit of measurement is arbitrary, and we should be
focusing on the achieved average of each test and percentage of difference. You
will notice variations in the data of each test. These variations are due to
slight size differences of a projectile depending on which mould cavity they
were cast from.
Before each test the sizing die
was thoroughly cleaned then washed with acetone, so I had an even starting
benchmark.
Data for 136 grain uncoated test shows the required force increases as the test progresses. It was noticed that the first 20 or so after being sized had a smooth shiny sized surface with minor striations. Required force increased and started to fluctuate and I noticed the sized projectiles surface turned dull and had deeper striations. Lead was starting to smear and stick to the inside surface of the sizing die and was causing increased friction.
The second test of the 136 grain was Hi-Tech coated. This shows a 49.3% reduction of required force on average compared to uncoated. Apart from a few outliers in the data the required force stayed consistent. Hi-Tek Supercoat alone provides lubrication.
Third test, Hi-Tech coated with Aqualube provided a further reduction of 49.5% (that is a total of 74.4% less force required than uncoated projectiles)
136 grain starting average diameter 0.3603 hardness 15-16 BHN sized using a Lee 0.356 die with a final sized diameter 0.3562, 4 thou reduction.
The next tests performed with 122 grain Flat Point were completed using the same process. Uncoated test provided similar data however, the 122 grain did not cause lead smearing on the die surface and the required force did not increase as more projectiles were sized. The projectile bearing surface appeared shiny with minor striations.
The second 122 grain test,
Hi-Tek Coated provided reasonably consistent data. It is noted the first few
projectiles sized gave a higher-than-average reading. That maybe because those
first four were just slightly oversized and or, the Hi-Tek coating started to
provide a lubricating factor. There is a 35.4% reduction compared to uncoated.
Third test, Hi-Tech coated with Aqualube provided a further reduction 46.5% (total of 65.5% compared to uncoated). 122 grain starting average diameter 0.360 – 0.362 hardness 15-16 BHN sized using
a Lee 0.356 die with a final sized diameter 0.3562, 4 – 6 thou reduction
Different style projectiles
induce varying forces required to push them through a sizing die. This appears
to be directly related to the shape and bearing surface area of the projectile.
Another benefit of Aqualube is
it does not contaminate or affect recoating of Hi-Tek Supercoat. should you
decide to apply another coat of Hi-Tek Supercoat after applying Aqualube
whether the projectile has been sized or not, recoating may be performed. Smash
tests have shown adhesion of further coats is not affected.
My findings are conclusive, Hi-Tek Aqualube provides a significant reduction in force required to size a projectile. Eases effort required for manual sizing and will reduce stress on automated sizing equipment.
In summary: J and M Specialzed Products
The 50ml bottle makes about 3.5 to 4.0 litres of lubricating mixture in denatured alcohol. This mixture is applied to casts, ready for sizing at a rate of about 2 ml to 250 projectiles. At this rate, it can be expected that you can dry-size lubricate about 350000 projectiles (or more) with 50 ml of the Aqualube concentrate. As I have stated, the product goes a very long way. It is a clean, dry-film lubricant. The experiments that were conducted by Michael amply demonstrate the effectiveness of Aqualube with sizing load reductions, previously I had no actual figures that I could quote, despite knowning that the product worked very well. Now we have actual results to back-up its effectiveness. -
