Low or High grain for copper ammo?

highlands

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I went to buy some copper ammo for my 243 Savage for deer hunting in California. I currently have 85 grain Federal Trophy copper ammo. I wanted to purchase 100 grain copper. The guy in the store told me to stick with the 85 grain. He said lower grain ammo is better for copper ammo. Would you agree?
 

Brnsvllyjohn

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I would say as a general rule yes a little lighter bullet is what most recommend. The reason is you need speed for dependable expansion and lighter is generally faster. Copper also retains about 90% or more of it's weight after expanding and it gives the same penetration or better than a lead core bullet that sheds a lot of weight after it expands. The down side is there is less shock from the rapid expansion so speed helps a little there. I shot 140 in my 7 mag and I used to shoot 150 or 160 grain in lead core bullets. I have not had a problem with copper yet as far as quick clean kills go. Others have. I have only recovered one bullet so most are complete pass throughs.
 

highlands

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I would say as a general rule yes a little lighter bullet is what most recommend. The reason is you need speed for dependable expansion and lighter is generally faster. Copper also retains about 90% or more of it's weight after expanding and it gives the same penetration or better than a lead core bullet that sheds a lot of weight after it expands. The down side is there is less shock from the rapid expansion so speed helps a little there. I shot 140 in my 7 mag and I used to shoot 150 or 160 grain in lead core bullets. I have not had a problem with copper yet as far as quick clean kills go. Others have. I have only recovered one bullet so most are complete pass throughs.
Thank you!
 

Revo2811

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I would say as a general rule yes a little lighter bullet is what most recommend. The reason is you need speed for dependable expansion and lighter is generally faster. Copper also retains about 90% or more of it's weight after expanding and it gives the same penetration or better than a lead core bullet that sheds a lot of weight after it expands. The down side is there is less shock from the rapid expansion so speed helps a little there. I shot 140 in my 7 mag and I used to shoot 150 or 160 grain in lead core bullets. I have not had a problem with copper yet as far as quick clean kills go. Others have. I have only recovered one bullet so most are complete pass throughs.
brnsvllyjohn does the 140 fly more flat then the 150 or 160?
 

Brnsvllyjohn

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brnsvllyjohn does the 140 fly more flat then the 150 or 160?

In round numbers compared to 160 the 140 drops 1-2 inches less at 400 and 2-3 inches less at 500 so not significant. This is from memory so not exact. Not much velocity difference at 4-500 yards either.
I shoot 140 because they shoot real well in my gun and since they are copper I dont worry about it being a lighter bullet. If I was still using lead core I would probably go back to 150 or 160.

Recoil might be a tad less with the 140 but not enough to really make a difference.

In my 7-08 I shoot Barnes some and I think they only load a 120 now. I used to shoot 140 or 150 in it.

The other problem is since we live in Ca. we have to find a copper load our guns will shoot and that can be challenge. It was easier when we could order by mail.
 

hntndux

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Good question, I reload/shoot copper in alot of calibers and normally I stick with the same weight as I shoot lead and all was good until it came to a .243 my son won at a CDA dinner. I for the life of me couldn't find a load for the 100's that didn't make the target look like you were using a shotgun. Then I learned about the effect of bullet length and barrel twist. Long for caliber bullets need more twist and this was the case with a .24cal 100gr copper bullet. I went down to the 85gr barnes and now it just makes the same hole bigger at 100yds. For the 100gr .24 I think you need at least a 1in9 twist.
 

dabob

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Many rifles from 6mm on down in size will not shoot the same weight copper or "lead free" bullets like they shot with lead bullets.

That is why most all of the 6mm lead free bullets are 85 grain or smaller.

The bullet manufacturers don't even make quite a few of the lead free bullet types in the same weight as lead bullets because they know most of the rifles out there have to slow of a twist barrel to shoot them.

Most 22-250 and 220 Swift rifles can't shoot above a 40 gr lead free bullet because the slow 1-12" and 1-14" twist rates will not stabilize the longer lead free bullets.

In California if you want 22-250 performance buy a 243 Win, they will shoot 55 gr to 62 gr lead free varmint bullets that are available and they have 80 to 90 gr big game copper bullets they will shoot good.

The 6mm caliber rifles and smaller are much more sensitive to lead free bullets because of their longer length than the rifles that are a bigger caliber. Even with the bigger rifles most hunters are using lead free bullets that are 10 gr to 30 gr lighter than the lead bullets that they used on big game.
 
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