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View Full Version : Heaviest Bullets that can be stablized in a 22/250 with the standard 1 in 14 twist?


William T. Watts
May 8, 2010, 10:26 PM
I have recently purchased a Winchester Model 70 featherweight in 22/250 that will group Sierra's 53gr match HP fine but will not group Sierra's 60gr HP or 63gr Semi pointed bullets worth a darn. Is this is what I should expect with a 1 in 14 twist?? I'm beginning to think a 55gr SP is about as far as I can go, this is my 1st 22cal center fire rifle and frankly I didn't know what to expect. I'm using R-P cases and IMR4064 CCI LR primers with Sierra's 53/60/63 gn Hp & Sp projectiles. Suggestions/comments? William

Shoney
May 8, 2010, 10:39 PM
I think you have pretty well figured it out. The 0224's with 14 twist were designed to be ideal for 50-52 gr bullets. It will stabilize the 55's.

Only the rarest of 14 twists may stabilize above 55.

Good Shooting!

tom234
May 9, 2010, 12:45 AM
http://www.riflebarrels.com/products/caliber_twist_rates.htm

http://www.shilen.com/calibersAndTwists.html

steveno
May 9, 2010, 03:09 AM
I have shot Nosler 60 grain ballistic tips in my Ruger #1B. they shot ok but not as good as 55 grain Noslers. the 60 grainers were around an inch at 100 yards and the 55 grainers will be touching at 100 yards

Scorch
May 9, 2010, 03:57 AM
Typically, for a 1:14" twist, 55 gr are the heaviest you want to load. It has little to do with bullet weight, it has everything to do with bullet length, so in most cases it depends on the bullet profile. Since 55 gr SPBT stabilize out of my 22-250, I tried Sierra 60 gr Semi-pointed flat base bullets, and they stabilized (trajectory sucked, but that is another matter). Nosler 60 gr Partitions stablize for many people, but you have to push them fast. Try whatever you are looking at, but realize that you will run into the twist problem.

William T. Watts
May 9, 2010, 10:05 AM
I referred to Sierra's loading manual before purchasing my Winchester 22/250, I used Sierra's recommended loads for all their bullets including the 60gr Hp and 63gr Semi pointed bullet with the expectation they would group reasonably well. I suspect the only way to achive reasonable accuracy is max loads with those two bullet weights which I am not willing to do. Final note, Sierra's test specifications list a 1 in 10 twist barrel for their 69 gr bullet only, from the way the foot note was written they didn't indicate their 60/63 gr bullets needing the faster twist to stabilize. Tnx for the responses and comments! William

FrankenMauser
May 9, 2010, 02:42 PM
If you have a longer barrel, want to push things a bit faster, and use slow-burning powders ... you can probably get 60-65gr bullets stabilized.

It's a balancing act of velocity and twist rate. The slower the velocity - the faster the twist rate needs to be. The slower the twist rate - the faster the velocity needs to be. This is the very reason most .220 Swifts have 1:14" barrels, as well. They use high speed and slower twist rates to achieve the same stabilizing bullet rpm as other .22 calibers do with 1:7", 1:9", and 1:10" barrels.

But, like others have said -
It doesn't matter what the theories say, if your barrel doesn't like anything over 55gr.

eaglesnester
May 9, 2010, 03:20 PM
Yup you got er figured out. 40-55gr is about the best you can do with that twist. Well maybe not. I have a 22/250 Weatherby Super Varmint Master 1-14twist and I am able to shoot Speer 70gr in it and am getting 1 inch groups at 100. I use Winchester 760 powder when loading 70gr. Normaly I shoot 52gr Burgers and get .038 inch groups at 100.

Unclenick
May 9, 2010, 04:25 PM
Stability for a given twist rate varies mainly with bullet length, but density and velocity play lesser rolls. The JBM on-line calculators include a twist and stability estimator at the bottom, here (http://www.jbmballistics.com/cgi-bin/jbmstab-5.1.cgi). Since air density is also a factor, it has you enter the temperature and barometric pressure, with U. S. Army Standard Meteorological conditions (Army Std. Metro.) as the default. And you can change velocity, mass and length of the bullet to see the effect.

The output is in the gyroscopic stability factor, s, which must be greater than 1.0 for a bullet to be stable. The combined wisdom of several authors suggests a value in the range of 1.4 to 1.7 is best for peak accuracy, with 1.5 being a good number to aim for. By substitution into that criteron, under Army Std. Metro conditions, if you can launch a 60 grain bullet at 3300 fps, then a bullet length range of 0.634" to 0.679" is best. At 3500 fps inches that goes up to 0.638" to 0.684".

William T. Watts
May 9, 2010, 11:02 PM
Uncle Nick the JBM on-line calculator made for a bit of interesting reading, if I understand correctly my Sierra 53 and 55 gr bullets will only marginal stablize at the velocities (3300-3400 fps) I want to drive them. Now I am down to trimming the meplat (I think I said that correctly) to shorten bullets in order to stabilize them or go to a lighter bullet. I didn't have any idea what I was getting into when I purchased this caliber rifle. I do have an extensive shooting (informal) background and 43 plus years handloading, but this is my first centerfire .224 cal rifle. Eventually I will get it figured out of that I am sure! Thanks for your help William

Scorch
May 10, 2010, 01:34 AM
FWIW, I have been shooting my 22-250 for 32 years, first with 52 gr Match HP, then with 55 gr SPBT, and never had an issue with them. Just because a piece of software tells you it won't work doesn't make it so.

FrankenMauser
May 10, 2010, 02:44 AM
Just because a piece of software tells you it won't work doesn't make it so.

Indeed. My .220 Swift absolutely loves powders with burn rates so slow I have to ignite them a week in advance ... even with 40gr bullets. Yet, my dad's .223 prefers powders near the speed of light - even for heavier stuff.

On the bullet side of the equation - my .270 Win doesn't like anything over 150gr, but my brothers' rifles will sling 160gr Partitions all day long. Mine also hates 130gr Winchester Ballistic Silvertips, but their rifles will punch tiny little groups with them (with little regard to powder charge). Their .270s do great with a moderate load of 4064 behind Speer 100gr HPs, but mine needs really stout (over max, I believe) load of H4895 to keep the HPs at about 1.5-2 MoA.

Sometimes, you just have to work with the hand you're dealt (the rifle's preferences, that is).

William T. Watts
May 10, 2010, 06:55 AM
The 60 and 63 gr bullets are yawing, the bullets aren't punching neat holes in the targets so they are out. The 53 gr MHP bullets are at or under 1", this is a featherweight rifle not a heavy barrel long tube variety. I haven't tried any full power loads nor have a used my chrony to clock any of the loads either. When I have more time to spend at the range I'll get a better feel for what I can do (translated when my wife has a business trip I get to spend more time shooting)! William

hagar
May 10, 2010, 09:39 AM
Try the 64 WW PP bullets with 38 grains of 4350 in your 22/250. It stabilized fine in my 24 and 26 inch barrels, but did not shoot that well in a 20 inch Micro medallion. It is a pretty awesome bullet for shooting bigger things like coyotes, and very accurate. It shot 1/3 inch groups out of my 22/250 BDL.

old_folks
May 14, 2010, 02:51 PM
For what its worth...i have had excellent results in getting the 63 gr Sierra to stabilize in a Ruger 77MK II VT using either H380 or IMR 4064, but keeping the velocity down about 3100 fps. Consistently getting 1/2 inch groups, and it does what I want it to do.

Good luck.

A_Gamehog
May 15, 2010, 08:45 AM
I had a 22-250 with a 1-14 twist, it would not shoot the Hornady 55's or anything heavier with accuracy. I just sold that gun and bought a new 22-250 with a 1-12 twist. It shoots the 55-60's made by Hornady. Ideal when wind is a factor.

Most of the 1-14 twist 22-250's will shoot the 55 Sierra BK and Nosler BT with ease because they are shorter.

boggie
May 17, 2010, 08:57 PM
I have a Tikka T3 in 22-250 thats shoots a 1 in group @ 100 yds with 55 gr. however it will shoot 1/2 in groups with 40 gr.