As I was nearing an end to a # of Unique I first opened on 1/21/16, It dawned on me to try something I’ve always wanted to do: Test different lots of a propellant, straight across, by volume. All summer, I’ve been extensively testing 45 ACP, 230gn bullets, using intermediate burn rate propellants. So this test would logically be an extension of that testing.
For the test, the bullet used is X-treme’s 230 PHP (plated hollow point); since I just purchased 2000 of them (came in a bucket and weighed almost 70 Lbs.), it seemed the logical choice. Charge weight was 5.5 grains. OAL 1.203” – I aimed for 1.200, so close enough.
My hopper is an RCBS Uniflow; I loaded 50 rounds at 5.5 grains. This took me near the end of the #; at which point, I emptied the hopper – not touching the 5.5 grain setting. This residual powder became lawn fertilizer. I then filled the hopper with the new lot of a previously unopened # of Unique. I weighed ten throws and got 55.8 grains. So the average throw weighed .08 grains more with the same volume. This surprised me because in times past, I’ve noticed even more of a difference between old and new #’s of powder – even with the same lot. Anyway, it is what it is. For the sake of records, I considered the new lot to have a charge weight of 5.6 grains. I loaded 50 rounds of these.
All of the above-mentioned ammo was loaded with once-fired (by me) brass from factory Winchester White Box ammo (230 ball ammo). This was done to deliver maximum consistency for the test. However, I also recently purchased 1K pcs of Starline 45 ACP+P brass. Starline says that they are built stronger for “unsupported chambers” – i.e. Glocks
– and have 2 grains (H2O) less internal volume than their non+P offering. So I figured this would be a good time to test this brass against the WWB.
So, using the same hopper setting, I loaded another 40 rounds, using the Starline +P brass.
Unique, 5.5 & 5.6 grains; CCI 300 primers; X-treme 230 PHP; WWB & *-*+P brass; shot through a Kimber full-size 1911. All data is from 20 round samples. Chronograph (Chrony Beta – or whatever it’s called) set at four yards, with diffusers, bathing in direct sunlight. 71 degrees Fahrenheit, slight south breeze coming from about the 5 o’clock position. I didn’t have the barometric pressure or humidity.
Old lot of Unique, WWB brass – 5.5 grains: 833.6 f/s; 20.81 SD
New lot of Unique, WWB brass – 5.6 grains: 825.2 f/s; 28.37 SD
New lot of Unique, *-*+P brass – 5.6 grains: 875.5 f/s; 23.88 SD
Remember, all three of these loadings are with the same hopper setting (volume). The difference with the Starline brass was a real eye opener. It is also interesting how the new lot of Unique has a higher density, yet seems to deliver less energy – or at least, a lower average pressure. Getting back to the brass, WWB brass, by casual observation, appears more cavernous than most. Looking down to the floor (where the flash hole is), they are very flat on the bottom and have a very sharp turn going up to the wall. By comparison, most other brands of brass are more “coved” on the bottom and leading up the wall – as is the Starline +P brass. So I believe my brass test here is likely a case of extremes. An eye-opener, none the less.
Another observation, the loaded rounds of the Starline brass show more distortion on the outside from the bullet insertion. They do indeed seem to be thicker brass.
To summarize, different powder lots do indeed make a difference. And in this case, the difference would have shown to be even greater had I conducted the test by weight – rather than volume. And yes, internal case volume can make a profound difference on burn rate, pressure, and performance. This is why using different bullets – even of the same weight – is not always an apples-to-apples comparison when looking at load data. Novice loaders, take particular notice here.
Since this range trip started with a clean gun (as always – I have never taken a dirty gun to the range) and I fired all 140 rounds – and only the 140 rounds – it made for an excellent opportunity to test how clean – or dirty – Unique runs. Pressure-wise, these rounds were fairly stout. So Unique should have been running pretty much right in its wheelhouse. Result: the gun was no more dirty or sooty than from any other range trip shooting a similar number of rounds. The moral of the story here is that any propellant will run clean if it’s being used properly. I did however observe a slightly tinged hue of orange throughout the barrel. This is a sign of copper plating breakdown. So I do believe I was over-driving the X-treme plated bullet. Further loadings with this bullet will be in the order of 5.2 grains or so – something in that neighborhood. They should make great range shooters at that level.
For the test, the bullet used is X-treme’s 230 PHP (plated hollow point); since I just purchased 2000 of them (came in a bucket and weighed almost 70 Lbs.), it seemed the logical choice. Charge weight was 5.5 grains. OAL 1.203” – I aimed for 1.200, so close enough.
My hopper is an RCBS Uniflow; I loaded 50 rounds at 5.5 grains. This took me near the end of the #; at which point, I emptied the hopper – not touching the 5.5 grain setting. This residual powder became lawn fertilizer. I then filled the hopper with the new lot of a previously unopened # of Unique. I weighed ten throws and got 55.8 grains. So the average throw weighed .08 grains more with the same volume. This surprised me because in times past, I’ve noticed even more of a difference between old and new #’s of powder – even with the same lot. Anyway, it is what it is. For the sake of records, I considered the new lot to have a charge weight of 5.6 grains. I loaded 50 rounds of these.
All of the above-mentioned ammo was loaded with once-fired (by me) brass from factory Winchester White Box ammo (230 ball ammo). This was done to deliver maximum consistency for the test. However, I also recently purchased 1K pcs of Starline 45 ACP+P brass. Starline says that they are built stronger for “unsupported chambers” – i.e. Glocks
– and have 2 grains (H2O) less internal volume than their non+P offering. So I figured this would be a good time to test this brass against the WWB.So, using the same hopper setting, I loaded another 40 rounds, using the Starline +P brass.
Unique, 5.5 & 5.6 grains; CCI 300 primers; X-treme 230 PHP; WWB & *-*+P brass; shot through a Kimber full-size 1911. All data is from 20 round samples. Chronograph (Chrony Beta – or whatever it’s called) set at four yards, with diffusers, bathing in direct sunlight. 71 degrees Fahrenheit, slight south breeze coming from about the 5 o’clock position. I didn’t have the barometric pressure or humidity
.Old lot of Unique, WWB brass – 5.5 grains: 833.6 f/s; 20.81 SD
New lot of Unique, WWB brass – 5.6 grains: 825.2 f/s; 28.37 SD
New lot of Unique, *-*+P brass – 5.6 grains: 875.5 f/s; 23.88 SD
Remember, all three of these loadings are with the same hopper setting (volume). The difference with the Starline brass was a real eye opener. It is also interesting how the new lot of Unique has a higher density, yet seems to deliver less energy – or at least, a lower average pressure. Getting back to the brass, WWB brass, by casual observation, appears more cavernous than most. Looking down to the floor (where the flash hole is), they are very flat on the bottom and have a very sharp turn going up to the wall. By comparison, most other brands of brass are more “coved” on the bottom and leading up the wall – as is the Starline +P brass. So I believe my brass test here is likely a case of extremes. An eye-opener, none the less.
Another observation, the loaded rounds of the Starline brass show more distortion on the outside from the bullet insertion. They do indeed seem to be thicker brass.
To summarize, different powder lots do indeed make a difference. And in this case, the difference would have shown to be even greater had I conducted the test by weight – rather than volume. And yes, internal case volume can make a profound difference on burn rate, pressure, and performance. This is why using different bullets – even of the same weight – is not always an apples-to-apples comparison when looking at load data. Novice loaders, take particular notice here.
Since this range trip started with a clean gun (as always – I have never taken a dirty gun to the range) and I fired all 140 rounds – and only the 140 rounds – it made for an excellent opportunity to test how clean – or dirty – Unique runs. Pressure-wise, these rounds were fairly stout. So Unique should have been running pretty much right in its wheelhouse. Result: the gun was no more dirty or sooty than from any other range trip shooting a similar number of rounds. The moral of the story here is that any propellant will run clean if it’s being used properly. I did however observe a slightly tinged hue of orange throughout the barrel. This is a sign of copper plating breakdown. So I do believe I was over-driving the X-treme plated bullet. Further loadings with this bullet will be in the order of 5.2 grains or so – something in that neighborhood. They should make great range shooters at that level.
. So I just now weighed 20 of each: