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Bayou Bullets 180 gr TCG, CZ 75 Tactical Sport .40, Alliant e3


johnsons1480

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Got some load data compiled from my range sessions. This seems to inconsistent when compared to the data I'm seeing around here for Alliant e3. Any thoughts here? My scale is calibrated, and I verified that my two 20 grain check weights weighed exactly 40 grains on my scale before and after I started. Averaged 10 throws before I started loading each batch.

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By inconsistant with what other report, do you mean velocity? Yours seems to be low.

There may be several factors at work here. First, you say that you weight ten drops and then start loading. Well the powder drop for the first loaded shell will differ from the second, and that will differ from the third and fourth. For the most accurate results, you should run at least 6 or 7 rounds before you start to collect the ones you will shoot in competition or chrono.

Second, your barrel might just be incredibly slow.

Third, your chronograph technique needs work. Unless you are firing all the rounds exactly down the axis of the chrono and dead parallel to the plane of the sensors, your reading will be slower than the actual velocity. Small variations can make astonishing differences.

I to load 180gr LTC and polycoated TC for my TS at 1.126" OAL. My Major load is 3.6gr e3 under a Falcoated 180gr for 172PF (950fps). 3.7 does it using leadTC bullets. SDs are always in the single digits. BTW, I don't get the velocity variation you report for the 4gr load at 72 and 58 deg. I get zilch.

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By inconsistant with what other report, do you mean velocity? Yours seems to be low.

Yes, velocity. Mainly based on your posts where you achieve major at 3.6-3.7 gr.

There may be several factors at work here. First, you say that you weight ten drops and then start loading. Well the powder drop for the first loaded shell will differ from the second, and that will differ from the third and fourth. For the most accurate results, you should run at least 6 or 7 rounds before you start to collect the ones you will shoot in competition or chrono.

I adjusted my powder measure, then dropped ten charges, then threw that back in the measure. Then I measured 10 charges to establish where my measure was at. Then I started loading. Isn't that the normal method?

Second, your barrel might just be incredibly slow.

That's what I'm starting to think.

Third, your chronograph technique needs work. Unless you are firing all the rounds exactly down the axis of the chrono and dead parallel to the plane of the sensors, your reading will be slower than the actual velocity. Small variations can make astonishing differences.

I haven't had a problem with the thousands of other rounds I've fired over my chrono. Seems a little harsh, but ok.

I to load 180gr LTC and polycoated TC for my TS at 1.126" OAL. My Major load is 3.6gr e3 under a Falcoated 180gr for 172PF (950fps). 3.7 does it using leadTC bullets. SDs are always in the single digits. BTW, I don't get the velocity variation you report for the 4gr load at 72 and 58 deg. I get zilch.

I don't get it either. That's the point of this post. I'm seeing what I believe to be temperature based velocity swings (which others have reported not to exist), and far higher charges than others have reported to reach the same PF. I loaded up about 200 4.2 gr bullets so I could dial in my sights better after doing the chrono session. I went ahead and fired most of them over the chrono because it was still set up, and I saw velocities that were consistent with my 10 round test group of 4.2 gr.

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Hmmm, that is a fair amount slower than what I am getting. My guess would be either you simply have a slow barrel or you have a slow lot of powder. Have not heard of this with E3. I used to see large swings in loading needs between lots with the IMR powders when I used them.

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Hmmm, that is a fair amount slower than what I am getting. My guess would be either you simply have a slow barrel or you have a slow lot of powder. Have not heard of this with E3. I used to see large swings in loading needs between lots with the IMR powders when I used them.

It seems like it would be one of those two. I was hoping someone would come along with chrono data for the Freedom Munitions ammo so I could narrow it down.

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j1480, you misinterpreted my post. I prefaced by writing "may be at work", not were at work. I was not criticizing your chrono technique, just passing along some info I learned the hard way. I always wondered why I got so much less velocity than the VV loading manual stated. After doing some quick calculations I discovered my chrono technique was a part of it. Any bullet path not directly down the long axis and parallel to the plane of the sensors is longer. So the time of flight is longer, and the chrono reports a slower velocity. If your off axis POA is consistent shot-to-shot, the reported velocities will be lower, but the SD will be accurate. If the paths are not consistent, both velocity and SD will be incorrect.

As far as powder drops are concerned, the only way to know what you are actually dropping is to operate the press until loaded rounds are dropping out, pulling the bullet out of the round under the seating die and weighing the powder. I do this several times. I have found that when I initially set up the charge before loading starts, I get consistent results. However, they are always heavier than what is thrown when actually loading. The vibrations of the machine and the way you operate it affect the way powder settles in the measuring chamber. The same thing happens if you have a jam up. The next drop is going to be off, so you better measure and correct it.

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j1480, you misinterpreted my post. I prefaced by writing "may be at work", not were at work. I was not criticizing your chrono technique, just passing along some info I learned the hard way. I always wondered why I got so much less velocity than the VV loading manual stated. After doing some quick calculations I discovered my chrono technique was a part of it. Any bullet path not directly down the long axis and parallel to the plane of the sensors is longer. So the time of flight is longer, and the chrono reports a slower velocity. If your off axis POA is consistent shot-to-shot, the reported velocities will be lower, but the SD will be accurate. If the paths are not consistent, both velocity and SD will be incorrect.

As far as powder drops are concerned, the only way to know what you are actually dropping is to operate the press until loaded rounds are dropping out, pulling the bullet out of the round under the seating die and weighing the powder. I do this several times. I have found that when I initially set up the charge before loading starts, I get consistent results. However, they are always heavier than what is thrown when actually loading. The vibrations of the machine and the way you operate it affect the way powder settles in the measuring chamber. The same thing happens if you have a jam up. The next drop is going to be off, so you better measure and correct it.

Fair enough. I was about 3" to the left at 18 yards. I didn't correct this until after the chrono sessions, and now my windage is dead on at 25 yds. I've got a new front sight coming in to correct my elevation, should be here in a day or two. I may very well repeat the whole ladder once I've got my sights dialed in. I have about 1,600 more Freedom Munition rounds to practice with before I have an actual need to start reloading.

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I have chrono'd these loads several times over the last couple years. I'm always double checking myself before a chrono'd match. CZ Tactical Sport.

3.7 E-3, 180 Bayou, Winchester SPP, 1.130OAL, 10 shot avg 918fps 165PF.

3.9 E-3, 180 Bayou, WSPP, 1.130OAL, 10 shot avg 947fps 170PF.

I use the 3.9 E-3.

It doesn't seem far off of johnsons1480

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