Horrible run out. 6/284

Jimbee

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I had a tikka 8 twist 243 barrel reamed 6/284.
I necked down 6.5/284 Lapua brass in a full length Redding die. Apparently the inside of the die was super dirty and I couldn't resize my fired brass with it until a gunsmith polished it for me. Anyways, I noticed some of the reloads looked a bit off. I rolled a couple on my reloading bench and watched the 108 eldm tips flop around like a bent pool cue. It doesn't seem to affect accuracy. image_cropper_1720988171215.jpg
 
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Jimbee

Jimbee

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using a 6.5 seater? Could the tip be bottoming out on the stem?
I was originally using a Hornady 7prc seating die with a 6mm stem. I now have a Frankford universal seating setup that didn't fix anything. I'm thinking it's the sizing die?
 
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I went through this battle and it drove me nuts. Making 25/284 I had terrible runout. Still at times I get random loaded rounds with as much as .015 runout. The 6.5x284 type s sizing die with bushing makes crooked necks on the brass. Ended ordering a regular 25/284 sizing die from Redding and that helped. Make sure you have the inside necks freshly deburred and the brass is clean. Those things have helped the most but still will get some wild ass runout if I measure every round. Good news is you can’t shoot the difference between the crooked ones and the straight ones. It will for sure aggravate any OCD you might have.
 
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Jimbee

Jimbee

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What barrel length do you have and velocity? Curious what a 6-284 does.
It's 17", with 49grains of H1000 I'm getting just a bit over 2700fps. I also have a 17" Tikka .243 that is getting about 50 more fps with H4350. I was expecting more speed, maybe a different powder would be faster?
 

TaperPin

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It's 17", with 49grains of H1000 I'm getting just a bit over 2700fps. I also have a 17" Tikka .243 that is getting about 50 more fps with H4350. I was expecting more speed, maybe a different powder would be faster?
I have a 6mm-06 and ran across this article - his velocities are for a 26” barrel, but his 06 case held a few less grains of water than fire formed 6mm-284, so it’s very similar. Anyway, thought you might like the load data.

 
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Jimbee

Jimbee

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I have a 6mm-06 and ran across this article - his velocities are for a 26” barrel, but his 06 case held a few less grains of water than fire formed 6mm-284, so it’s very similar. Anyway, thought you might like the load data.

Much appreciated!
 
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It's 17", with 49grains of H1000 I'm getting just a bit over 2700fps. I also have a 17" Tikka .243 that is getting about 50 more fps with H4350. I was expecting more speed, maybe a different powder would be faster?
I ran up to 56grains of h1000 behind a 135 Berger in the 25/284. 49grains is super lite charge
 
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It's 17", with 49grains of H1000 I'm getting just a bit over 2700fps. I also have a 17" Tikka .243 that is getting about 50 more fps with H4350. I was expecting more speed, maybe a different powder would be faster?
I ran up to 56grains of h1000 behind a 135 Berger in the 25/284. 49grains is super lite charge
I get ejector marks at 50 grains.
thats really weird.
 

Harvey_NW

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Any theories?
Just a theory, and I don't have any first hand experience with finding data or loading for Wildcat-284 (yet..), but I have read about excessive headspace and too low of a charge allowing the case head to slap the bolt face and produce ejector marks that are actually false pressure signs.

Were you testing with fireformed brass?
Any bolt lift, or just ejector mark?
Where did you get your data?
 
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