I have recently been testing a new powder just
introduced by IMR Powder Company that is called
"Trail Boss". As the name suggests, it is aimed
squarely at Cowboy Action Shooters, but it is entirely suitable
for any moderate velocity handgun loads, and it would be selling
the powder short to limit its use to only the sport of Cowboy
Action Shooting. To quote from IMR’s website:
"Trail Boss is designed specifically for
low velocity lead bullet loads suitable for Cowboy Action
shooting. It is primarily a pistol powder, but has some
application in rifle. It is based on a whole new technology
which allows very high loading density, good flow through powder
measures, stability in severe temperature variation and most
importantly, additional safety to the handloader."
As stated, IMR’s intention was to achieve four
things, and I will address them one at a time.
First, the powder was developed to have a high
loading density. In other words, to better fill the cartridge
case without leaving a lot of room in the case after the bullet
is seated. This is important for a couple of reasons. One is
that a case that is full of powder usually gives more consistent
performance with lower velocity variations and better accuracy.
Another reason is that high loading density makes it much easier
to spot a case in the loading process that either received no
powder charge, or received a double powder charge. Neither
condition is desirable. A cartridge with no powder can stick a
bullet in the bore, and a cartridge with a double charge can
cause the gun to come apart in the shooter’s hand upon firing,
sometimes taking valuable parts of that hand along with it. As
can be seen in the photos, Trail Boss offers high loading
density. With recommended loads, the case is practically full,
leaving just enough room for the bullet to be seated. Trail Boss
is a relatively fast pistol powder, comparing closely to Alliant
Bullseye, Hodgdon’s Clays and other powders of similar
burning rate. However, it is easy to miss a cartridge case in
the loading process that has a double charge of some of these
other fast powders, such as Bullseye. Trail Boss, on the other
hand, will overflow its case if a double charge is mistakenly
thrown. The photos show how 6.1 grains of Trail Boss compares to
6.1 grains of Bullseye. Both give close to the same velocities
with a 200 grain lead bullet in a .45 Colt, but Trail Boss has
optimum loading density for that cartridge case. In their effort
to achieve better loading density, IMR has excelled with their
new Trail Boss powder.
Another of IMR’s goals was to achieve better
flow characteristics through powder measures. I tried Trail Boss
through three different automatic powder measures, and the
results were, for lack of a better term, perfect. Trail Boss
flows as well or better than any powder that I can think of at
this time. The charges thrown were very consistent, with weight
variations that were undetectable by my scale, if they existed
at all. There was also no tendency to bind in any of the powder
measures in which it was tried, of either the slide or rotating
drum type.
IMR also stated a criteria of stability in
extreme temperature variation, of which I made no attempt to
perform any test. All of my testing was done under very
comfortable conditions of about seventy-five degrees.
IMR's last stated goal was that of additional
safety for the handloader, which is the most important, and
relates directly to their success in achieving higher loading
density.
With most all of my hand loading, I try to use a
powder which fills the cartridge case, with the exception of
relatively low-velocity silent loads in rifle cartridges. Many
shooters like to use a faster powder, and then fill the rest of
the case with things like Dacron, cornmeal, Grex, grits, felt,
and a number of other things, none of which belongs in a
cartridge case. I like to use smokeless powder and nothing else
in my handgun cartridges. With high-performance top end hunting
loads, this is easily achieved in magnum handgun cartridges
using such wonderful powders as Hodgdon’s
Lil’Gun and H110, or Winchester’s 296, or a
few other relatively slow-burning handgun powders. The problem
of double-charged cartridges comes into play with light to
moderate loads in handguns that are used for casual plinking,
target shooting, or in the sport of Cowboy Action Shooting. Most
participants in the fast-growing sport of Cowboy Action Shooting
use relatively mild loads in their revolvers and lever action
carbines. Trail Boss powder, by virtue of its high loading
density, is very suitable to the loads used in that sport.
I tested the new Trail Boss powder in several
handguns and six different cartridges. The results are listed in
the chart below. Velocities are listed in feet-per-second.
Bullet and powder weights are listed in grains.
| Cartridge |
Firearm |
Bullet |
Powder Charge |
*Vel |
*AD |
| .32 H&R Mag |
6-1/2" Ruger Single Six |
100 LSWC |
2.4 grains |
790.1 FPS |
12.2 |
| .38 Spec |
6" Ruger GP-100 |
158 LRN |
4.1 grains |
785.8 FPS |
9.1 |
| .357 Mag |
6-1/2" Ruger BH |
158 LSWC |
4.1 grains |
828.2 FPS |
10.8 |
| .44 WCF |
7-1/2" Colt NF |
200 LFN |
6.4 grains |
844.6 FPS |
7.7 |
| .44 Spec |
4-5/8" Ruger BH |
200 LFN |
6.4 grains |
864.4 FPS |
15 |
| .45 Colt |
5-1/2" Ruger Vaq |
200 LRN |
5.1 grains |
565.6 FPS |
15.6 |
| .45 Colt |
5-1/2" Ruger Vaq |
200 LRN |
6.4 grains |
775.5 FPS |
13.3 |
*Bullet weight (in grains)
**Vel = Velocity (feet per
second)
***AD = Average Deviation
All six revolvers tested turned in accuracy as
good as the weapon has performed in the past, limited by the
ability of this shooter. Groups measured at twenty-five yards
ran from less than one inch to just over three inches, depending
upon the weapon. The Trail Boss powder offered very consistent
velocities, and burned clean, leaving little residue and no
unburned powder. The fragrance of the burned powder was very
pleasant, if that is an important consideration. It is to me. I
used Winchester primers throughout the tests, and ignition was
perfect with all loads tested. Loading density was ideal in all
loads tested, filling the cases, but needing no compression of
the charge to seat the bullet.
Trail Boss is a single base high-energy powder
that is not only suitable for Cowboy Action shooters, but for
any handgunner loading standard velocity loads for target
shooting, plinking, or small game hunting. Trail Boss is also
capable of performing well in moderate velocity loads suitable
for hunting medium game such as whitetail deer. However, it is
ideally suited for the type of loads used in the sport of Cowboy
Action Shooting, and I predict that with these handgunners,
Trail Boss will excel to become the preferred powder of that
sport. In a field of excellent pistol powders, Trail Boss
is that good. It is a powder that is, for lack of a better term,
fluffy. It is very bulky for its weight, giving it the desired
high loading density. A standard one-pound-sized can holds only
nine ounces of Trail Boss. However, its cost per grain is
comparable to other powders in its class, and will add nothing
to the practical cost of shooting your favorite handguns.
Handloaders today have a seemingly endless list
of available powders from which to choose. I use many different
powders, depending upon the cartridge. However, I do have some
long-time favorites for handgun cartridges, such as WW231, HP38,
Universal, Unique, Titegroup, H4227, Lil’Gun, H110, and WW296.
I now have a new favorite to add to that list: IMR’s Trail
Boss. After using up just one can, I am impressed, and I highly
recommend it.
For more information on Trail Boss, and for
Trail Boss loading data, go to: www.imrpowder.com.
Jeff Quinn
Got something to say about this article? Want to agree (or
disagree) with it? Click the following link to go to the GUNBlast Feedback Page.
