Is 8.5 twist too fast for 284 Win

[bobeager]

Any experiences that can be shared regarding a 8.5 twist in a 284 Win?

 

[Steve Blair]

Most people use 9" twist for 180 Hybrids, probably the most difficult to stabilize bullet commonly used. I have a couple 8.5" twist blanks in case Berger ever produces the 195 Hybrid. [br]
If you are running 175-180 grain bullets, that twist should be fine.

 

[DennisH]

I am shooting Berger 180's with a 9 twist. My SD & ES are perfect, both under 8. Very accurate rifle.

I doubt you would be shooting any heavier bullet .

10 is recommended for the Berger 180

Just my .02's worth.

Dennis

PS: What bullet are you planning on shooting in your 284? Give me the bullet details & length and I will run it through a twist calculator.

 

[Steve Blair]

I am shooting Berger 180's with a 9 twist. My SD & ES are perfect, both under 8. Very accurate rifle.

I doubt you would be shooting any heavier bullet .

10 is recommended for the Berger 180

Just my .02's worth.

Dennis

PS: What bullet are you planning on shooting in your 284? Give me the bullet details & length and I will run it through a twist calculator.

[br]Wouldn't perfect be zero for both? [br]
Berger recommends 9" twist or faster for 180 Hybrids. Here is a link to Berger's Quick Reference Sheet. [br]
http://www.bergerbullets.com/pdf/Quick-Reference-Sheets.pdf

 

[DennisH]

Wouldn't perfect be zero for both?

About as close as you can get! LOL

To be exact: SD=1 ES = 2

Series 1 Shots: 4
Min 2920 Max 2922
Avg 2921
S-D 1
ES 2

RL17
BR2 CCI
180 Hybrids


Series Shot Speed
1 1 2922 ft/sec
1 2 2920 ft/sec
1 3 2922 ft/sec
1 4 2920 ft/sec

Berger recommends 9" twist or faster for 180 Hybrids. Here is a link to Berger's Quick Reference Sheet.

I will stick with the 9 twist

 

[BradY]

Impressive Dennis, but surely you arent basing it on only 4 shots... Wouldnt you look at a string of 15-20 as a better indication?

 

[TonyR]

I had a 284 Shehane 1:8.5 twist barrel that blew up a lot of the old thin jacket Berger 180 VLDs when the MV got up to 2900 fps. Shot lights out at 2800 fps with no problems so I just shot it there. Probably wouldn't be any problem with a straight 284 Win and the new thicker target jackets like the use with the 180 Hybrids.

 

[DennisH]

Impressive Dennis, but surely you arent basing it on only 4 shots... Wouldnt you look at a string of 15-20 as a better indication?

Those reading were took when I was trying to find a load for the 284.

I chrono it often since I am using RL17, and the results are always about the same.

Since I am happy with the performance @ 600yds, and the readings are always about the same, I don't see a need to go further and only test 4 to 5 rounds.

I do agree with your suggestion of 15-20 round strings and have done it on other guns that were not easy to tune.

My 284 results once I found them are unbelievable and I left it alone. And as stated above, there always about the same. I never have shot it with temp's below 50deg's. Anywhere from 50 to 90 deg's was the avg temp's.