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  #11  
Old 06-01-2019, 05:22 PM
champ0608 champ0608 is offline
 
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Location: AZ
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Quote:
Originally Posted by libertyman777 View Post
Does the twist rate matter with respect to this issue?
I doubt it. Both instances were in 1:7 white oak Wilson barrels. Pretty standard for what everyone is using. But I was pushing them pretty hard. 23.5 grains of H4895. Velocities over 2800.
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  #12  
Old 06-02-2019, 04:43 AM
milprileb milprileb is offline
 
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Quote:
Originally Posted by libertyman777 View Post
Iím going to try these in my 1/8 RRA takeoff that Iím building on.

By the way, @milprileb , your call sign seems very familiar. Did you used to frequent the Swiss Rifle forums or similar?
Yes, I own two K31's, boring accurate with any ammo. Not much to say on Swiss forums , its all the same thing ...accuracy. Nothing ever new there...accuracy accuracy.
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  #13  
Old 06-03-2019, 06:17 PM
Gewehr43 Gewehr43 is offline
 
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Location: Denver, CO
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Ive found it hit/miss with the 75HPBT's.
Some rifles love them and some don't.

BTW.....since I know you like shooting LR with the 223, I found the 75's lost it somewhere 700-900yds. They did not make it to 1000yds. 600 or in shot great, after that, not so much.

For me....they aren't as good as the 80SMK's at 600 though. That's just my experience though.

PS.... if you do want to blow up bullets..... shoot the Hornady SX bullets thru a 1/7 barrel.
They definitely don't handle that twist and speed well...…..
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Last edited by Gewehr43; 06-03-2019 at 06:21 PM.
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  #14  
Old 06-17-2019, 05:31 PM
milprileb milprileb is offline
 
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Quote:
Originally Posted by Gewehr43 View Post
Ive found it hit/miss with the 75HPBT's.
Some rifles love them and some don't.

BTW.....since I know you like shooting LR with the 223, I found the 75's lost it somewhere 700-900yds. They did not make it to 1000yds. 600 or in shot great, after that, not so much.

For me....they aren't as good as the 80SMK's at 600 though. That's just my experience though.

PS.... if you do want to blow up bullets..... shoot the Hornady SX bullets thru a 1/7 barrel.
They definitely don't handle that twist and speed well...Ö..
Since you've validated they won't hang past 600, I'll not buy another box but I do like their accuracy at 600 yds which had me wondering ...not wondering anymore , so thank you.
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  #15  
Old 06-19-2019, 01:15 AM
Gewehr43 Gewehr43 is offline
 
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Location: Denver, CO
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Sir:
Im not telling you what to do. Those were my experiences for you to consider.
They might shoot great for you out to 1000yds, they didnt for me.
But yes, out to 600yds, they did shoot great..... mid 190's at 600.
But Ive shot high 190's with 80's.
I did have one rifle that did not like them at all. (Im not at home or I'd look up my notes and give you any clues I had on it).
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  #16  
Old 06-21-2019, 11:07 AM
milprileb milprileb is offline
 
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Thank you for all your insights , I appreciate it greatly.
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  #17  
Old 03-24-2020, 10:29 PM
cdl2 cdl2 is offline
 
Join Date: Feb 2010
Location: Ohio
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I have an upper that 1/12 twist that I sot a lot 55 gr thru
Two questions, can I shoot 68 gr thru the 1/12 twist?
A also bought a upper with a 1/7 twist to shoot the 68 gr ammo
What will happen if I shoot 55 gr thru the 1/7 twist barrel?
I have an older AR 15,. Up graded the lower with a two stage RR trigger I built up a new upper with 1/7 twist, but I still want to shoot the older 1/12 twist upper.
Thanks
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  #18  
Old 03-25-2020, 05:20 PM
Gewehr43 Gewehr43 is offline
 
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Quote:
Originally Posted by cdl2 View Post
I have an upper that 1/12 twist that I sot a lot 55 gr thru
Two questions, can I shoot 68 gr thru the 1/12 twist?
A also bought a upper with a 1/7 twist to shoot the 68 gr ammo
What will happen if I shoot 55 gr thru the 1/7 twist barrel?
I have an older AR 15,. Up graded the lower with a two stage RR trigger I built up a new upper with 1/7 twist, but I still want to shoot the older 1/12 twist upper.
Thanks
I don't know if 68's will stabilize in a 1/12" barrel.
Shoot them and see...Ö It'll be obvious with poor accuracy and bullets keyholing.

The 55's will shoot fine in a 1/7" barrel.
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  #19  
Old 03-26-2020, 11:28 PM
Louisxllx Louisxllx is offline
 
Join Date: Oct 2009
Location: Austin, Texas
Posts: 364
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The Sierra 60 grain flat base varmint bullets have shot very well for me in 1-12 barrels. Also in 1-7.8 barrels. Berger 64 grain bullets came apart in my 26 inch 1-7 Lija barrel.
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  #20  
Old 03-28-2020, 12:39 AM
HighpowerRifleBrony HighpowerRifleBrony is online now
 
Join Date: Nov 2015
Location: Texas
Posts: 165
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1:12 is limited to ~0.750" long bullets. 1:7 will shoot quality short bullets well.

This one measures 1:7.7, but 50gr VMAX is my short range bullet of choice in everything, including Dad's 1:6.5 CLE -
https://www.youtube.com/watch?v=5AEPwOa623I

I reference these links a lot -
http://www.jbmballistics.com/ballist.../lengths.shtml
https://bergerbullets.com/twist-rate-calculator/
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