AA4064 vs AA4350 - Strange Results

[Chief TC]

I made loads for my 1903A3 using 168gr Hornady HPBT. I already knew the AA4064 load was a good load but wanted to compare it to AA4350. 4350 powders tend to be best for 180gr bullets but still a powder listed for 168gr bullets. The AA4064 performed as expected, 6 o'clock hold and hitting all targets up to 500yds.

With AA4350, I used the amount of powder to match the velocity of AA4064. It grouped fine but had a very different POI than AA4064. As compared to POI with AA4064, 4350 impacted per the following: at 200, it impacted a few inches lower; at 300, it impacted about the same; at 500, it impacted much higher than AA4064.

I know 4350 burns slower than 4064. Since I have been reloading, which is only about 5 years, I have never seen this before where a powder has a wide array of POI. Whether Varget or IMR4064 or AA4064, once I have the load dialed in, it has a POI that is consistent at all distances with a 6 o'clock hold. I shot quite a bit yesterday and the results were consistent, so it takes me out of the equation.

I use IMR and AA 4350 for 178 and 180gr bullets and works as I described above like you think it would. So I am interested in thoughts here. Thanks!

 

[25-20 WCF]

We need more information to answer your question accurately.
How many shots in each group at each range?
How large were the groups at each range?
What were the velocities and ES for each load?


.

 

[Chief TC]

We need more information to answer your question accurately.
How many shots in each group at each range?
How large were the groups at each range?
What were the velocities and ES for each load?


.

Ahhh, I did not chrony, so cannot give you that info. If I do 4350 again, I will be sure to do all that.

5 shots at 200, 300 and 500. Grouping was 1 MOA at 200, 2 MOA at 300 and 500

 

[Slamfire]

Is the barrel on my M1903A3 issue, and how many shots are in the groups you are evaluating.

Even though IMR 4350 is slower than IMR 4895 or IMR 4064 (or AA4064), it still shoots well with 150 and 168 grain bullets. This was a little hot, so I cut the charge later to 57.0 grains

this load was too hot, which revealed itself as more rounds were put downrange

IMR 4895 shot well at 300 yards with 168's

H4350 shot well with 175's

and so did IMR 4064. Differences in elevation were insignificant out to 300 yards. But I am not shooting a service rifle, this Mauser has a heavy match barrel.

I do not have enough shots on any of these targets to prove that one powder is much better than the other. Though my 600 yard target with IMR 4064 was the best of the series. But given that I am not shooting in a vacuum, does not prove much.

Back in the day for NRA across the course, two good "standard" loads were a 168 match with 47.0 grains IMR 4895 or 55.0 grains IMR 4350.

 

[Chief TC]

Is the barrel on my M1903A3 issue, and how many shots are in the groups you are evaluating.

Even though IMR 4350 is slower than IMR 4895 or IMR 4064 (or AA4064), it still shoots well with 150 and 168 grain bullets. This was a little hot, so I cut the charge later to 57.0 grains

this load was too hot, which revealed itself as more rounds were put downrange

IMR 4895 shot well at 300 yards with 168's

H4350 shot well with 175's

and so did IMR 4064. Differences in elevation were insignificant out to 300 yards. But I am not shooting a service rifle, this Mauser has a heavy match barrel.

I do not have enough shots on any of these targets to prove that one powder is much better than the other. Though my 600 yard target with IMR 4064 was the best of the series. But given that I am not shooting in a vacuum, does not prove much.

Back in the day for NRA across the course, two good "standard" loads were a 168 match with 47.0 grains IMR 4895 or 55.0 grains IMR 4350.

Many thanks Slamfire for some education. Always appreciate the effort you put into your responses. Will study and ponder more.

 

[Skgreen]

With AA4350, I used the amount of powder to match the velocity of AA4064

Ahhh, I did not chrony,

I'm confused,,,, If you didn't chrony, how do you know you're matching velocity?

 

[JimGnitecki]

With AA4350, I used the amount of powder to match the velocity of AA4064

Ahhh, I did not chrony,

I'm confused,,,, If you didn't chrony, how do you know you're matching velocity?

He may be relying on published load tables, which is NOT a good idea. I have found that the velocities in published load tables are pretty unreliable when applied to specific rifles with differing barrel lengths and different preferences.

Jim G

 

[Chief TC]

All true, I loaded based on published data and did not chrony. But here is the issue - even without knowing the exact velocities of each load, they are not drastically far apart. With AA4064, the POI was consistent and expected using a 6 o'clock hold at all distances. With AA4350, also using 6 o'clock hold, the POI at 200 was POA; POI at 300 was about 8 inches above POA, 500 was about 20 inches above POA. Never seen or experienced this before. Why does the POI rise??? Maybe this was heat mirage? But I typically don't shoot that it heats up the barrel super hot and this was in low light conditions.

I will plan on repeating this experiment and using the chrony.

 

[CoalCrackerAl]

Wow Slamfire. Im impressed with your groups.

 

[Skgreen]

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