Point of impact change

I had to change lot# on my H4350 that I use to load 30-06. Brass, primer,bullet and OAL all the same I even shot some I had loaded with the other lot# just to make sure. So as always I started at min an worked up to my standard load 57gr with 168 nosler Combined Technology bullet. I have done this in the past with good results. This time all is well but the point of impact dropped over 3 inches I have not seen this much change before. I didn't have my chronograph to see if velocity was that far off. Have I just been lucky in the past or is this normal????

I have never had that big of a change in trajectory with a different lot #...very odd. 3 inches?

As long as all other components and environmental influences are the same...I'd suspect a bad batch of powder or a change in formula at the factory.

Call and ask about the huge difference between the two batches....

I wonder if anyone has a calculator that would determine the difference in fps buy using the amount of drop...you'd prolly still need the fps from the "good" loads to start with......but 3 inches still has me baffled, that's like adding an extra 100 yards or so...

so you did shoot some from previous batches along with the new batch and only the new batch shot low?

I'm sure you checked your scope, but thats always a good place to start.

Has the weather cooled off much where you live? I went shooting the other day in a snowstorm, pretty early for where I'm at. Maybe you had a thick coat on that messed with your getting the rifle in your shoulder or eye relief.

Just thinking aloud here.

hawcer wrote:I have never had that big of a change in trajectory with a different lot #...very odd. 3 inches?

As long as all other components and environmental influences are the same...I'd suspect a bad batch of powder or a change in formula at the factory.

Call and ask about the huge difference between the two batches....

I wonder if anyone has a calculator that would determine the difference in fps buy using the amount of drop...you'd prolly still need the fps form the "good" loads to start with......but 3 inches still has me baffled, that's like adding an extra 100 yards or so...

I will talk to hodgdon but like you said thats a lot of diff. I got the powder at the same time I should have checked the lot #s then. I have had changes before but man this was way more than I have seen before. I will be going back to the range asap to run more tests. I have 3 rds of the old lot # left but I need to load some more with the new one. I hope it was just something I did. I may turn out that it will shoot well and just need to adjust the scope . I have had one of those years with my rifles( loose scopes, funny acting powder).

XbonesX wrote:I'm sure you checked your scope, but thats always a good place to start.

Has the weather cooled off much where you live? I went shooting the other day in a snowstorm, pretty early for where I'm at. Maybe you had a thick coat on that messed with your getting the rifle in your shoulder or eye relief.

Just thinking aloud here.

All the rounds were shot in the same time frame some just min. apart. I would shoot a few of one lot and a few of the other . I loaded them all the same day to. The min start loads (two each 55.0,55.5,56.0,56.5gr) and were fired first . They were shot at 25yd. Then I let the barrel cool for 20min. and moved to 100yd wish I had shot them all at 100yd to give me a better pic of what was happening.

The only other thing I could think of was hodgdon shortened the powder granules when the labeled it as an "Extreme Powder" for less temperature sensitivity...but seeing how you purchased them both at the same time...that theory goes out the window...

H4350 is also picky as far as primers go(so I've read)...but I'm sure you are using the same primers as before.

restest and re-submit....

Update


I went back to the range . At 100yds I fired the 3 rds I had left loaded with the lot# of H4350 powder that I had used to work up my load. I had made up 10 more with the new lot#. The point of impact on the first 3 were dead on. I fired 3 of the new lot and they were 3.5 inches low. I adjusted the scope and the last 7 rds went back to dead on 6 of the group was under 1.5 with one flyer.
I have not received a reply from Hodgdon. As I said this is the first time I have seen this much difference when just changing lot#s. I'm glad that they still shoot well but I will be doing more testing next week to see if they are good out past 100yds.