Verticle Spreading and load development help - where to go from here?

fnlights

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Hi All,

So I have a Bergara Premier Highlander in .300 Win Mag that I am working on some hand loads for. I am using Berger 215's, H1000, Norma Brass, CCI 250's, and Redding Type-S Bushing Dies. Gun will be primarily used for elk hunting out west.

I followed Berger's starting point of 70.5 grains of H1000, and shot .015, .020, and .030 off the lands.

See the first imagine below - the .030 off the lands shot the best (by far). (Image without a circle)

So, 70.5gr is pretty light for H1000 in a .300 WM, and decided to bump the powder charge up to 74gr (imagine with the red circle). This caused the groups to open up. This had zero pressure signs.

Question is, from here, do I bump up to say 75 gr and keep going until I see pressure - then tweak the seating depth again? Was hoping that the powder increase would not open the groups that much. I am new to this precision reloading.
 

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sedancowboy

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Keep going with your seating depth test. If .030 shot best then maybe .045 will be still better and .060 still better yet. Go until your groups open back up then you will know what seating depth is best.
Then at the best seating depth do a powder test and go up slow increasing by .5 grs of powder at at time. Don't just jump to 75 and hope for the best. I will bet you will find what you are looking for some where in those parameters.
Good shooting and good luck.
Henry
 

Roughrice

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I used CCI 200 with H1000 and IMR7977. Those primers worked fine for me. Groups were slightly better with H1000. That was with 208 ELDM's.
I was around 75.5 gr H1000.
Velocity was 2980ish.
 

Roughrice

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I used CCI 200 with H1000 and IMR7977. Those primers worked fine for me. Groups were slightly better with H1000. That was with 208 ELDM's.
I was around 75.5 gr H1000.
Velocity was 2980ish.
Forgot to mention... That was 300 WM out of 26" barrel.
208 ELD-M seated 20k off and shoots 1/2 moa.
 

fnlights

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Keep going with your seating depth test. If .030 shot best then maybe .045 will be still better and .060 still better yet. Go until your groups open back up then you will know what seating depth is best.
Then at the best seating depth do a powder test and go up slow increasing by .5 grs of powder at at time. Don't just jump to 75 and hope for the best. I will bet you will find what you are looking for some where in those parameters.
Good shooting and good luck.
Henry
So you think that I should go back down to the 70.5gr and keep trying seating depths?

I just hate to use 70.5gr of H1000 and finding the best seating depth with that because it is such a light round - I imagine that the velocity is rather low with this. Should I be testing the seating depths at a higher charge? I just used what Berger said at 70.5
 

338 dude

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Hi All,

So I have a Bergara Premier Highlander in .300 Win Mag that I am working on some hand loads for. I am using Berger 215's, H1000, Norma Brass, CCI 250's, and Redding Type-S Bushing Dies. Gun will be primarily used for elk hunting out west.

I followed Berger's starting point of 70.5 grains of H1000, and shot .015, .020, and .030 off the lands.

See the first imagine below - the .030 off the lands shot the best (by far). (Image without a circle)

So, 70.5gr is pretty light for H1000 in a .300 WM, and decided to bump the powder charge up to 74gr (imagine with the red circle). This caused the groups to open up. This had zero pressure signs.

Question is, from here, do I bump up to say 75 gr and keep going until I see pressure - then tweak the seating depth again? Was hoping that the powder increase would not open the groups that much. I am new to this precision reloading.
That’s a big jump in powder i usually advance half grain charges until I get close then go down to .3 grain charges then when I am happy with that group and no pressure signs I will adjust seating depth
 

fnlights

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That’s a big jump in powder i usually advance half grain charges until I get close then go down to .3 grain charges then when I am happy with that group and no pressure signs I will adjust seating depth
I agree it is a big jump in powder - I just knew that 70.5 gr of H1000 for Berger 215's is probably like 2500 fps - seems that everyone uses about 74-77 gr in their 300 WMs.

I just don't know why Berger recommends starting so low for the 215's - I feel that when I increase the powder charge, it will change the seating depth that the gun likes?? - but like I said, this is the first real load development I have ever done so I do not know if that is truly what happens
 

338 dude

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I agree it is a big jump in powder - I just knew that 70.5 gr of H1000 for Berger 215's is probably like 2500 fps - seems that everyone uses about 74-77 gr in their 300 WMs.

I just don't know why Berger recommends starting so low for the 215's - I feel that when I increase the powder charge, it will change the seating depth that the gun likes?? - but like I said, this is the first real load development I have ever done so I do not know if that is truly what happens
Lawyers!
 

Bullmark

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You haven’t mentioned your FPS....which leads me to believe you aren’t using a chrono??? It may not be what you want to hear but I’m betting that the members (of this forum) that are the most experienced and knowledgeable, will suggest getting a chrono to measure speed and ES. And letting the charge weight and seating depth placate the lowest ES.
If you are planning on shooting animals at long distances, knowing you have a predictable and reliable fps factor is kinda important......hence the requirement for a low ES.
Good luck and I’m just as interested as a you to hear from some of the guys that will chime in and show you the way.
 

fnlights

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Messages
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Location
Pennsylvania
You haven’t mentioned your FPS....which leads me to believe you aren’t using a chrono??? It may not be what you want to hear but I’m betting that the members (of this forum) that are the most experienced and knowledgeable, will suggest getting a chrono to measure speed and ES. And letting the charge weight and seating depth placate the lowest ES.
If you are planning on shooting animals at long distances, knowing you have a predictable and reliable fps factor is kinda important......hence the requirement for a low ES.
Good luck and I’m just as interested as a you to hear from some of the guys that will chime in and show you the way.
I have a chrono - I just have not set it up yet because I saw no sense in putting it together and taking it down with a starting load of 70.5 gr of H1000 - which from a .300 WM is a charge that I do not think anyone would shoot because its probably only 2,500 fps - not ideal from a .300WM.
 
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fnlights

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H1000 is very scare so I understand why you did what you did, but as mentioned bump up a 1/2 a grain at a time until the groups tighten up or you hit pressure.
HA YEP that is exactly why I am asking everyone on here for the "best" next step - hate to be wasting valuable primers and powder.

Should I be bumping up from the 70.5 or the 74gr? Also, do you recommend 3 shot groups or 5?
 

Rick Richard

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HA YEP that is exactly why I am asking everyone on here for the "best" next step - hate to be wasting valuable primers and powder.

Should I be bumping up from the 70.5 or the 74gr? Also, do you recommend 3 shot groups or 5?
1/2 grains from the starting load and 3 shot groups. Also, is this barrel broken in yet? Now with that said, I usually start a couple or three grains lower WHEN I find pressure signs and work up
 

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