Gents!
Which conventional 50 grain Soft point is most likely to stabilize in a 1-16" twist?

Minimum legal weight is 50 grains and that is on the borderline to stabilize with a spitzer bullet. I think a Short, Flat point, blunt bullet have a larger chance of beeing stable than a boat tail spitzer.

Unfortunately most manufacturers omit information on length, BC and SD on their products.
So, the question is, which bullet is most likely to be stable?

Sincerely

Daniel

The only one that comes to mind is the pudgy little Sierra SMP #1320. I've only used them with a 1:14 twist on varmints.

You can determine the stability of any bullet if you know the weight and length by using a stability (Twist) calculator and fill in the data yourself. Here are some online calculators:

http://www.jbmballistics.com/cgi-bin/jbmstab-5.1.cgi

http://www.bergerbullets.com/twist-rate-calculator/

http://www.mcgowenoutlet.com/twistcalculator.html

http://kwk.us/twist.html

In my experience the Stability Factor in the JBM Calculator should be at 1.5 minimum, and for some bullets I prefer something closer to 2.0.

I ran the numbers on the Sierra .224 50 grain Spitzer Blitz Medium Velocity bullet in my reference collection. Bullet length is 0.655". In a 1:16" twist that bullet with a muzzle velocity of 2,405 fps (IMR 4227), using the default temperature and pressure settings, has a stability Factor of 0.890 or unstable.

In a 1:14" twist barrel the Stability Factor increases to 1.163 or Marginally Stable.

In a 1:12" twist barrel the S. F. is 1.583 or Stable.

Be very cautious of trying to cheat with anything other than a flat base spitzer, as the weight will still be 50 grains, and I haven't found many flatpoint .224" bullets, Hornady makes a 45 grain HP BEE bullet but that is underweight. My opinion, from personal experience, is that too slow a twist can't be compensated for with varying bullet shapes. Experimentation with various twists had led me to adopt faster than standard twists in most instances, with .224" barrels being a minimum of 1:9" twist.

If you want a legal class2 round you might consider to rechamber it to a K-hornet. Try normas 50gr flatbase bullet in your rifle and see if it stabilisize.

A .221 rem fireball would make a nice class 3 in the gun wardrobe with possibility to load it to class 2 levels.

Gents, Thanks for replies!

Nordic, That is exactly what I am considering!

But, before re-chambering I would like to test if a bullet (and which one) will stabilize in the 1-16" twist.

In the swedish system with a limited gun wardrobe, a class 3 and class 2 combo is hard to beat, even if it would reduce the rifle to a one shot rifle in class 2. I think the legal issues are only understood by those that are affected by the rules in the 3 affected counties.

The different calculators are a good tool, but the problem here, is that I have not found any manufacturer that publish the length of the bullets. 1 out of 3 publish SD, none publish length.

Norma´s 50 grain bullet is one of the top candidates, SAKO is also possible, as well as S&B, but none have a published length to put in to the calculators... None of the above are found in a local store.

I have the 50gn PRVI partizan that I will test as soon as I get some spare time. It is slightly shorter than the 40gn hdy v-max. At calculated k-hornet velocities it is marginally stable at around 1,5 if I recall correctly.

Instead of randomly buying any and all 50gn softpoints the web has to offer, I ask for opinions on which candidates that would be most likely to stabilize so I can narrow down the search to a few. Since it is on the margin of stabilizing I could end up with a dozen un-stable bullets before finding one that will be stable.

This weekend I will be harrassing beavers at dusk with the .375HH from a moose high-seat 80 m / 90 yd from the beaver hut & dam. If I could find a stable 50gn bullet and rechamber to k-hornet, I could use that instead... That´s kind of the niche it would fill. Since I do not have a class 2 rifle, I have to use my .375...

The .221 Fireball is a good round but it involves a bit more work for the gunsmith and most likely also a new barrel since the twist issue remains. Why reballel if I can get away with rechambering?

For now, the K-hornet is the first choice, after finding a 50 gn "deer" bullet that will stabilize out to ca 120 yd, which is around 30 yd farther than I consider maximum ethical distance. For longer ranges, the .375 puts down everything that walks.

If I cannot get a 50gn bullet to stabilize, then the re-chambering to K-hornet looses some of its appeal, and .221 fireball increases its appeal...

So, the question remains, which 50gn SP bullet is most likely to be stable in a 1-16" twist?

Sincerely

Daniel

Expostulating on "twist theory" seems to be the fashion de jure.

There are no hard and fast rules regarding twist rates. Barrels vary in they way they behave and bullets certainly vary in the way they behave.

A given 50 grain bullet may or may not show acceptable accuracy in your Hornet, but the only way you'll know is to try it. Among the "bluntest" of spitzers is the Speer 50-grainer (the conventional lead-tipped bullet, not the TNT). I would suggest trying it. I seem to recall that the Sierra semi-pointed .224" bullets are now out of production (the 45 grain Sierra SMP was a great favorite of mine in the Hornet, damnit.) In the end, I would be very surprised if you couldn't find a bullet/powder combination which yields sufficient accuracy for your purposes.

But to help you find the shortest bullets, which will have the best chance of stabilizing in a relatively slow-twist barrel, consult this excellent repository of information:

http://www.shootforum.com/forum/bulletdb.html

I shot a beaver with .222r and 55gr sierra spbt(deer bullet) the bullet splintered in the spine and no exit hole. So i consider 50/55gr marginal on beaver. If you shoot at shorter distance so you can make headshots both the .375 and .22hornet would be perfect.
To make 800j at 100m you cant have a bullet with bad ballstics and a blunt nose might not have the needed performance on roe and beaver.
Maybee a cast bullet would fit your need.