Powder Compression Value

Discussions of powders, bullets and loading information.

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opencountry
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Powder Compression Value

Post by opencountry »

A simple question.
My stock of Goex Fg has finally come to an end. I have a question someone hopefully has an answer to. With a good stock on hand of Swiss 1F I’m wondering if different lots of this Swiss 1F need different compression values to obtain peak performance. I always got by with the same compression value using different lots of Goex Fg in my 45-110’s. Any experience with this? FWIW, granulation size in the varying lots of Swiss 1F I currently have look different.

Robert
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bpcr shooter
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Re: Powder Compression Value

Post by bpcr shooter »

I start with .085-.095 compression. that usually gets me on paper at 300yd. I do shoot PP, so I mostly only seat bullets .100 in the case

matt
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opencountry
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Re: Powder Compression Value

Post by opencountry »

Thanks Matt. I’ll start here. I’ve been using a .030” vegi wad to compress, add a .060” poly, then a Sagebrush felt wad.
Thanks for the help.
Robert
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TexasMac
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Re: Powder Compression Value

Post by TexasMac »

Robert,

Unless you're using the extra wads to reduce the powder charge I would start with a .060" wad, .010" to 0.020" of compression & with the bullet nose or a driving band in firm contact with the leade. Then work up loads with increasing compression until you see them start to group on the target. Although Swiss generally does not need a lot of compression compared to Goex, after extensive testing my Sharps 1874 prefers 0.270" of compression using Swiss 1.5Fg with a BACO money bullet. There's no compression common denominator that applies to Swiss. It all depends on what you rifle & bullet combination likes.

Wayne
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desert deuce
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Re: Powder Compression Value

Post by desert deuce »

Texas Mack wrote: "There's no compression common denominator that applies to Swiss. It all depends on what your rifle & bullet combination likes."

Yes, and to reaffirm for example, going from 45-70 to 45-90 with the same lot may require a different compression.

The target is or should be the deciding factor.
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martinibelgian
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Re: Powder Compression Value

Post by martinibelgian »

Never looked at compression values when loading BP - just powder weight; and compression is whatever it is. Makes it that much simpler.
opencountry
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Re: Powder Compression Value

Post by opencountry »

martinibelgian wrote: Mon Sep 26, 2022 10:51 am Never looked at compression values when loading BP - just powder weight; and compression is whatever it is. Makes it that much simpler.
So, I take what you said as meaning - you stay with a certain compression value (setting), and add or reduce your powder weight until you find that sweet spot.
I guess I do this as well, although once I find a good charge of powder I then work on compression values to fine-tune things even more.
An old owner of the Harley Davidson shop here where I live always said, “Whatever blows your skirt up.” I think that statement covers everything well. Each to their own.
Robert
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martinibelgian
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Re: Powder Compression Value

Post by martinibelgian »

Robert,

Yes and no - I don't even take compression into consideration, except the starting point - which is powder level to the base of the bullet, the 'no compression' point. From there onwards, I just look at powder weight, and compression is just a consequence - the powder is always compressed to the same depth, regardless of powder charge.
opencountry
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Re: Powder Compression Value

Post by opencountry »

I understand. While we’re here may I ask you this question…do you find that with the change of the powder lot the weight of the charge ‘sometimes’ changes, making it necessary to work up a new load?
Robert
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opencountry
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Re: Powder Compression Value

Post by opencountry »

Forget the last question, Martin. After reading your reply again I think you’re onto something. Im going to try this with my pp reloading.
Thank you,
Robert
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AzTBH
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Re: Powder Compression Value

Post by AzTBH »

TexasMac wrote: Sun Sep 25, 2022 10:43 pm Robert,

Unless you're using the extra wads to reduce the powder charge I would start with a .060" wad, .010" to 0.020" of compression & with the bullet nose or a driving band in firm contact with the leade. Then work up loads with increasing compression until you see them start to group on the target. Although Swiss generally does not need a lot of compression compared to Goex, after extensive testing my Sharps 1874 prefers 0.270" of compression using Swiss 1.5Fg with a BACO money bullet. There's no compression common denominator that applies to Swiss. It all depends on what you rifle & bullet combination likes.

Wayne
Wayne

Is the 0.270” of compression being used in your 40-65 load?

Thanks,
Ross
Ross McCollum
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