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Author Topic: 22-250 Rate of twist  (Read 689 times)

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Offline Casefiller

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22-250 Rate of twist
« on: June 18, 2005, 12:18:12 AM »
Could someone help me out with the twist on the 22-250 ?

Thanks,

CF
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Offline Datil

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Twist
« Reply #1 on: June 18, 2005, 12:26:53 AM »
I think it is 1 in 12,  22-250 is not list in FAQ's  If not right someone
 will come on and correct me.  Marv.
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Offline Casefiller

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22-250 Rate of twist
« Reply #2 on: June 18, 2005, 12:30:08 AM »
Thanks Marv for the fast reply. I am still searching for the "right bullet " fir this NEF
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Offline 218Bee

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22-250 Rate of twist
« Reply #3 on: June 18, 2005, 04:19:30 AM »
Thanks for bringing this up Casefiller, I've been meaning to bring this up for a while now.

My crude attempt to measure the twist come up with 1 rotation to 14" but my chinamart cleaning rod doesn't have a real good bearing on the handle.

I have been seeing better result with a 40Gr VMax, but haven't pursued that bullet much since I intend to use it mainly for coyote. I've been concentrating more on 55Gr bullets in SPSX and VMax.

I'll work up a few more 40Gr loads. The best I came up with was 34gr of Varget, 40gr Vmax, 2.46" COAL.

Rick
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Offline McLernon

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22-250 Twist Rate
« Reply #4 on: June 18, 2005, 05:24:02 AM »
The standard twist rate for a 22-250 is 1:14, however I believe Savage employs a twist rate of 1:12.

In cold weather you may have some trouble stabilizing the 55 gr Vmax. My 22-250 has an actual measured twist rate of 1:14.75 and it will not stabilize 55 gr. Nosler bal tip below 10 degrees C.
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Offline Casefiller

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22-250 Rate of twist
« Reply #5 on: June 19, 2005, 01:00:43 AM »
Bee, I shot the exact load with 40gr. + Varget   produced a 1" group at 100yards..  Shot a G hog yesterday with that load and a C/T 40 gr.  Durn near blew off his front shoulder.
I gonna call customer service and answer this question. I'll post what I find out

CF
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Offline 218Bee

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22-250 Rate of twist
« Reply #6 on: June 19, 2005, 03:42:13 PM »
CF

I have a short term memory problem :-D You turned me on to that load last month. I never went beyond full grain steps with it.

Looks like the greenhill tables support the 40 grainers if it turns out to be 1:14.

 Minimum Trist
20gr = 33.0
40gr = 16.5
60gr = 11.0
80gr = 8.3
100gr = 6.6
120gr = 5.5

Rick
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Offline Bluetix

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22-250 Rate of twist
« Reply #7 on: June 20, 2005, 01:06:25 AM »
Don't forget that rate of twist and bullet weight are not necessarily parallel such as the above chart suggests.  VELOCITY, barrel length, and pressure will all affect bullet stabilization. :D
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Offline Casefiller

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22-250 Rate of twist
« Reply #8 on: June 20, 2005, 04:29:43 AM »
From the mouths of Customer Service: The answer is 1:14
Thanks for all the replies

Gonna try H380 and 55's next.....maybe !
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Offline myarmor

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22-250 Rate of twist
« Reply #9 on: June 20, 2005, 05:11:27 AM »
I don't know many that own the 22-250 Handi around here.
How do the Winchester White box ammo shoot through them? What kind of groups?
As good as the 223 WWB ammo?
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Offline fuzzy

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W box 22-250
« Reply #10 on: June 20, 2005, 09:25:21 AM »
I haven`t had much luck with the W box 45 grain stuff mine likes 55`s
Fuzzy
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Offline Bluetix

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22-250 Rate of twist
« Reply #11 on: June 21, 2005, 12:15:46 AM »
Quote
The math to figure RPM of a bullet for a given velocity in a given twist barrel is real simple. It is:

RPM = (Velocity * 60 * 12)/Twist (in inches)

Using that formula, you can plug in some real world numbers and quickly see what I mean about it taking a lot of velocity to make up for a little bit of twist. For example, a bullet with a muzzle velocity of 3500 fps leaves a 12 twist barrel at 210,000 rpm. Using a 14 twist barrel, you have to increas the velocity all the way to 4080 fps, an increase of nearly 600 fps, to get the same spin as the 12 twist at 3500 fps.

Moral of the story... With notable exceptions, for the most part, you can't get there from here, trying to make up for a slower twist by means of increased velocity.


Saw this and just thought I would pass it along...real good info!
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Offline 218Bee

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22-250 Rate of twist
« Reply #12 on: June 21, 2005, 12:50:06 AM »
CF,

Mine was leaning towards 34.5 gr H380, 55Vmax, Mag Win primer. But that needs further work. I may go back to CCI200 and rework the load.

Rick
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Offline Casefiller

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22-250 Rate of twist
« Reply #13 on: June 21, 2005, 04:50:43 AM »
Hi Bee,  
 I have been messing with OAL and I feel this might be the key.  Bluetix saw some of my reloads for my Handi, he said: They look kinda long.
What I have been doing is taking a resized case and slitting it with a thin saw and seating the bullet, just in the mouth of the case, I close the action and let the rifling set the bullet back in the case. Measure OAL subtract .010 This only works with the bullet that you intend to reload due to ogive on bullet.

Beware of pressure signs, Im not seeing any

Maybe Im all wet......don't think so

Best of luck Rick, keep me posted and I'll do the same

CF
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Offline 218Bee

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22-250 Rate of twist
« Reply #14 on: June 22, 2005, 04:21:29 PM »
CF

I used the "pinch the neck" of an unsized case method.

Mine liked a OAL of 2.46 in the above load. Lands were measured as 2.48, the I generally subtract .02 as a starting point.

Rick
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Offline fuzzy

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Climent
« Reply #15 on: June 23, 2005, 01:37:52 PM »
I got a pm from some one on the temp i was shooting the 55 grains out of my 22-250 barrel some how i lost the PM so to whome it may consiren.
id say between 70-85 deg`s. Im useing win siver box 55 sps and pmc 55 sps Fuzzy
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