OpticsTalk by SWFA, Inc. Homepage SWFA     SampleList.com
Forum Home Forum Home > Firearms, Bows, and Ammunition > Reloading & Ballistics
  New Posts New Posts RSS Feed - What TWIST RATE for which bullet weight
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

Visit the SWFA.com site to check out our current specials.

What TWIST RATE for which bullet weight

 Post Reply Post Reply Page  <1234>
Author
Message
Urimaginaryfrnd View Drop Down
MODERATOR
MODERATOR
Avatar
Resident Redneck

Joined: June/20/2005
Location: Iowa
Status: Offline
Points: 14651
Post Options Post Options   Thanks (0) Thanks(0)   Quote Urimaginaryfrnd Quote  Post ReplyReply Direct Link To This Post Posted: January/17/2010 at 01:49
http://le.atk.com/pdf/223_MinimumTwistRates.pdf    Your best performance will be with bullets no longer than .829 inch with a 1:9 twist.   The 69 gr bullet is .900 I would suggest you measure the length of the 60 gr AMAX Horniday and try that fot the 1:9 twist.
 
You can shoot the 77 but it may not be as tight as it would with something in the 55 to 60 grain weight.   Try it and see what you get.  Note some 75 and heavier bullets have to be single shot loaded especially the 80 gr.

"Always do the right thing, just because it is the right thing to do".
Bobby Paul Doherty
Texas Ranger
Back to Top
RONK View Drop Down
Optics Master Extraordinaire
Optics Master Extraordinaire
Avatar

Joined: April/05/2007
Location: United States
Status: Offline
Points: 3199
Post Options Post Options   Thanks (0) Thanks(0)   Quote RONK Quote  Post ReplyReply Direct Link To This Post Posted: January/17/2010 at 11:32
Originally posted by cowski cowski wrote:

i have a 9 in twist will it work with 77 gr sierra's?
 Could go either way.
Shoot them to find out. It's the only way to know.
 You're on the borderline though, in my estimation.
Back to Top
koshkin View Drop Down
MODERATOR
MODERATOR
Avatar
Dark Lord of Optics

Joined: June/15/2004
Location: United States
Status: Offline
Points: 12999
Post Options Post Options   Thanks (0) Thanks(0)   Quote koshkin Quote  Post ReplyReply Direct Link To This Post Posted: January/17/2010 at 14:30
Originally posted by RONK RONK wrote:

Originally posted by cowski cowski wrote:

i have a 9 in twist will it work with 77 gr sierra's?
 Could go either way.
Shoot them to find out. It's the only way to know.
 You're on the borderline though, in my estimation.

77gr is a little heavy for 1 in 9 twist.  It might work well, but chances are you will do better with a lighter bullet.  My 1 in 9 twist 223 seems to really like 69gr SMKs.

ILya
Back to Top
GetSome View Drop Down
Optics Journeyman
Optics Journeyman
Avatar

Joined: December/12/2009
Location: Oregon
Status: Offline
Points: 516
Post Options Post Options   Thanks (0) Thanks(0)   Quote GetSome Quote  Post ReplyReply Direct Link To This Post Posted: January/17/2010 at 14:40
I would like to try some 77 gr. in my .223  1in8...does the military use sierra?  And I would assume it would have to have a cannalure, so is that set back far enough to allow a  crimp and still feed through a mag without single loading...I would imagine it would have to.  Any info you have would help I don't know anyone I could ask about the 77s locally.
Back to Top
koshkin View Drop Down
MODERATOR
MODERATOR
Avatar
Dark Lord of Optics

Joined: June/15/2004
Location: United States
Status: Offline
Points: 12999
Post Options Post Options   Thanks (0) Thanks(0)   Quote koshkin Quote  Post ReplyReply Direct Link To This Post Posted: January/17/2010 at 15:45
Originally posted by GetSome GetSome wrote:

I would like to try some 77 gr. in my .223  1in8...does the military use sierra?  And I would assume it would have to have a cannalure, so is that set back far enough to allow a  crimp and still feed through a mag without single loading...I would imagine it would have to.  Any info you have would help I don't know anyone I could ask about the 77s locally.

I am pretty sure there are two varieties of 77gr SMKs: with cannelure and without it.  I have only used the ones without cannelure, so I can't comment on the other ones.

ILya
Back to Top
Dale Clifford View Drop Down
Optics Jedi Knight
Optics Jedi Knight


Joined: July/04/2004
Location: United States
Status: Offline
Points: 5087
Post Options Post Options   Thanks (0) Thanks(0)   Quote Dale Clifford Quote  Post ReplyReply Direct Link To This Post Posted: January/17/2010 at 17:54

note -- one of the inputs is length

Back to Top
Dale Clifford View Drop Down
Optics Jedi Knight
Optics Jedi Knight


Joined: July/04/2004
Location: United States
Status: Offline
Points: 5087
Post Options Post Options   Thanks (0) Thanks(0)   Quote Dale Clifford Quote  Post ReplyReply Direct Link To This Post Posted: January/17/2010 at 17:58
yes the military uses the smk for the long range load. the bc is still only around .4 so wind drift is still a factor, especially when the load is shooting below 3000 fps.
Back to Top
scooter65 View Drop Down
Optics Master Extraordinaire
Optics Master Extraordinaire
Avatar

Joined: December/29/2006
Location: mi
Status: Offline
Points: 3567
Post Options Post Options   Thanks (0) Thanks(0)   Quote scooter65 Quote  Post ReplyReply Direct Link To This Post Posted: January/24/2010 at 08:56

Great chart Wes... I was just looking for a cross reference chart like this and walla!  I couldn't find the link online for it.  I captured the chart image in a .jpg file if anybody would like it so they can just print the chart off. 

uploads/4389/twistrate.zip

Edited by scooter65 - January/24/2010 at 12:46
Back to Top
pyro6999 View Drop Down
Optics Retard
Optics Retard
Avatar
OT TITAN

Joined: December/22/2006
Location: North Dakota
Status: Offline
Points: 22034
Post Options Post Options   Thanks (0) Thanks(0)   Quote pyro6999 Quote  Post ReplyReply Direct Link To This Post Posted: January/24/2010 at 11:53
lilja barrel company has a very nice chart as well, i have a copy of it printed out that i keep near my computer so when im looking at rifles and potential bullet combos in those rifles i can look at the twist rates and decide if its worth a shot or not.
http://www.riflebarrels.com/products/caliber_twist_rates.htm


Edited by pyro6999 - January/24/2010 at 11:53
They call me "Boots"
375H&H Mag: Yeah, it kills stuff "extra dead"

343 we will never forget

God Bless Chris Ledoux
"good ride cowboy"
Back to Top
scooter65 View Drop Down
Optics Master Extraordinaire
Optics Master Extraordinaire
Avatar

Joined: December/29/2006
Location: mi
Status: Offline
Points: 3567
Post Options Post Options   Thanks (0) Thanks(0)   Quote scooter65 Quote  Post ReplyReply Direct Link To This Post Posted: January/24/2010 at 12:46
Originally posted by pyro6999 pyro6999 wrote:

lilja barrel company has a very nice chart as well, i have a copy of it printed out that i keep near my computer so when im looking at rifles and potential bullet combos in those rifles i can look at the twist rates and decide if its worth a shot or not.
http://www.riflebarrels.com/products/caliber_twist_rates.htm
 
THANKS!  Saved to my favorites list now.
Back to Top
koshkin View Drop Down
MODERATOR
MODERATOR
Avatar
Dark Lord of Optics

Joined: June/15/2004
Location: United States
Status: Offline
Points: 12999
Post Options Post Options   Thanks (0) Thanks(0)   Quote koshkin Quote  Post ReplyReply Direct Link To This Post Posted: January/24/2010 at 18:19
Berger Bullets website lists the recommended twist rate for every bullet they make.

ILya
Back to Top
trigger29 View Drop Down
Optics Master Extraordinaire
Optics Master Extraordinaire
Avatar
X = 180 Y = 90 (X+Pyro)+(Y-Pyro) = ?

Joined: September/29/2007
Location: South Dakota
Status: Offline
Points: 4353
Post Options Post Options   Thanks (0) Thanks(0)   Quote trigger29 Quote  Post ReplyReply Direct Link To This Post Posted: January/24/2010 at 19:23
Originally posted by Dale Clifford Dale Clifford wrote:

note -- one of the inputs is length

Dale, I noticed that the stability factor changes with velocity. We all know that bullets don't stay the same velocity after they leave the barrel, so I was wondering, if your velocity is 2900 with a stability factor of 1.135 What happens when the bullet gets to 1900 fps, and the stability factor drops to .986. Will the bullet destabilize, and start to tumble or wobble?

"A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed."
Back to Top
The Apostle View Drop Down
Optics Journeyman
Optics Journeyman
Avatar

Joined: August/20/2009
Location: Adelaide, S.A.
Status: Offline
Points: 409
Post Options Post Options   Thanks (0) Thanks(0)   Quote The Apostle Quote  Post ReplyReply Direct Link To This Post Posted: February/13/2010 at 02:13
I'm going to get some bulk Federal Gold Medal Match in .308 Win...my Ruger is 1:10 twist...Which would suit my rifle best...168gr?...175gr?...or both???
Back to Top
SVT_Tactical View Drop Down
MODERATOR
MODERATOR
Avatar
Chief Sackscratch

Joined: December/17/2009
Location: NorthCackalacky
Status: Offline
Points: 30848
Post Options Post Options   Thanks (0) Thanks(0)   Quote SVT_Tactical Quote  Post ReplyReply Direct Link To This Post Posted: February/13/2010 at 08:09
Normally the faster twist will stablize a heavier bullet.  I would try both to see which provided better accuracy, if they are equal then get teh 175. It will fight the wind better than the lighter grain.  With a 10 twist you may even be able to put some bullets up to 200gr or even the 208 hornady a max.  I know this doesn't really answer your question so if I had to say one of the two it would be the 175 because of wind drift
Back to Top
Urimaginaryfrnd View Drop Down
MODERATOR
MODERATOR
Avatar
Resident Redneck

Joined: June/20/2005
Location: Iowa
Status: Offline
Points: 14651
Post Options Post Options   Thanks (0) Thanks(0)   Quote Urimaginaryfrnd Quote  Post ReplyReply Direct Link To This Post Posted: April/25/2010 at 20:43
Salute

"Always do the right thing, just because it is the right thing to do".
Bobby Paul Doherty
Texas Ranger
Back to Top
300S&W View Drop Down
Optics God
Optics God
Avatar

Joined: January/27/2008
Location: Burlington,WV
Status: Offline
Points: 10592
Post Options Post Options   Thanks (0) Thanks(0)   Quote 300S&W Quote  Post ReplyReply Direct Link To This Post Posted: April/25/2010 at 21:01
 Anyone familiar with this:
 
"I ain't got time to bleed!"
Back to Top
budperm View Drop Down
Optics Retard
Optics Retard
Avatar
show me your sheep!!

Joined: January/01/2009
Location: Pennsylvania
Status: Offline
Points: 30628
Post Options Post Options   Thanks (0) Thanks(0)   Quote budperm Quote  Post ReplyReply Direct Link To This Post Posted: May/06/2010 at 07:31
Interesting link Earl!  I will have to save it and study it when I have more time!
"Peace is that brief glorious moment in history when everybody stands around reloading".
--Thomas Jefferson



Back to Top
300S&W View Drop Down
Optics God
Optics God
Avatar

Joined: January/27/2008
Location: Burlington,WV
Status: Offline
Points: 10592
Post Options Post Options   Thanks (0) Thanks(0)   Quote 300S&W Quote  Post ReplyReply Direct Link To This Post Posted: May/06/2010 at 07:33
  Worked for me when I had to decide what rate of twist I wanted my 9.3 rebored to. Ended up at 1-12.
"I ain't got time to bleed!"
Back to Top
Bigdaddy0381 View Drop Down
MODERATOR
MODERATOR
Avatar
Georgia peach

Joined: February/27/2007
Location: Georgia
Status: Offline
Points: 13486
Post Options Post Options   Thanks (0) Thanks(0)   Quote Bigdaddy0381 Quote  Post ReplyReply Direct Link To This Post Posted: May/18/2010 at 09:20
Originally posted by trigger29 trigger29 wrote:

Originally posted by Dale Clifford Dale Clifford wrote:

note -- one of the inputs is length

Dale, I noticed that the stability factor changes with velocity. We all know that bullets don't stay the same velocity after they leave the barrel, so I was wondering, if your velocity is 2900 with a stability factor of 1.135 What happens when the bullet gets to 1900 fps, and the stability factor drops to .986. Will the bullet destabilize, and start to tumble or wobble?
 
 @50 yards this .243 with a 115gr berger it shot fine under1/2 group, now @100 the hit side ways. I'm not sure of the FPS on this load but as it slowed just a tad it started to flip. I guess most if it would depend on the bullet itself. as it might just have a yaw and not tumble. i want to say this is from a 1-10. I went with a 95gr for this rifle and it loves them out to 500 so far.
 
See they hit side ways.
 
 
P&Z Firearms , Pro gun cleanings and gun repair and wood refinishing.

Ecclesiastes 10:2
Back to Top
Dale Clifford View Drop Down
Optics Jedi Knight
Optics Jedi Knight


Joined: July/04/2004
Location: United States
Status: Offline
Points: 5087
Post Options Post Options   Thanks (0) Thanks(0)   Quote Dale Clifford Quote  Post ReplyReply Direct Link To This Post Posted: May/19/2010 at 08:01
while  the bullet decreases in speed, the rotational rate stays the same, so the amount of revolution per unit of distance traveled remains the same it takes more time to do it at the slowed velocity rate. Upon firing the base of the bullet is accelerated faster than parts of the bullet above this, (obtruation sp?). the more weight in the back causes better bc, but also gives more of shuttlecock effect. HBWC are an extreme example. At some point a bifurcation or change of a parameter in the relation between the inertial masses  of the front and back and the tumbling occurs. Pitch and yaw are different.
Back to Top
 Post Reply Post Reply Page  <1234>
  Share Topic   

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 12.01
Copyright ©2001-2018 Web Wiz Ltd.

This page was generated in 0.309 seconds.