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90 grain Secnar? What else?

Big game up to and including elk and black bears.
95 Bergs....
According to Bryan Litz, the 95 Berger won't even stabilize under the worst environmental conditions in a 1-10 twist, much less come anywhere near reaching its BC potential, and neither will the 90 Scenar.

With a 1-10 twist probably the best compromise is a 95 Ballistic Tip, but it's gonna drift more than bullets suitable for a 1-8 or even 1-9.
My first 6mm Stuver (6mm-6.5x55 Ackley) had a 10 twist. Shooting a bit faster than a 243, but velocity doesn’t make such a huge difference with stability as does twist.

Stabilized 95 Berger VLDs just fine as far as I wanted to shoot them, at 3000 feet ASL.
My 10 twist stabilizes 105's at 3050 fps just fine.
I've read reports of a 90 scenar doing very well out of a 1-10" Kimber Montana
Guys, David lives at around 500 feet above sea level.
And I hunt at only 1,000 feet
I have 300 85 grain TSX to shoot through for hunting at less than 500 yards, arguably a lifetime supply, and realistically the outer limit for me shooting where I hunt.

I'm trying to decide if I should keep my 1 in 8" 243 AI on a rem 700 action, or a tikka t3.

I really don't need both.
I shoot the 90 gr Accubonds to sub-moa groups and have punched a 4 round group at 500 that measured smaller than a business card. Load is with IMR 4350.
I have a load with 85 gr Partitions that impacts 1/2" higher than the 90 grain AB's and shoot sub MOA with it as well. That load is with IMR 4064.

Chrono on the 90 grainers is 3175 and on the 85's is 3225. The rifle is a Weatherby S2 Vanguard 24" 1-10 barrel.

90% of my hunting is at 1500' elevation or less.
Originally Posted by David_Walter
90 grain Secnar? What else?

Big game up to and including elk and black bears.


Hunting very big game such as those with a 90 gr bullet is not a good idea. "Long range" yet! frown
Originally Posted by David_Walter
And I hunt at only 1,000 feet


Who cares what you shoot, I just want to find a place to shoot elk at less than 1000 feet in elevation...
Originally Posted by Mule Deer
According to Bryan Litz, the 95 Berger won't even stabilize under the worst environmental conditions in a 1-10 twist, much less come anywhere near reaching its BC potential, and neither will the 90 Scenar.


What about the Berger Classic hunting bullet designed to work in a 10 twist barrel? It has a BC of .427, not quite as good as the Scenar (.434) but not that far behind. Sierra 100 grain Gameking is .430, I know everyone dogs Sierra but they've always worked for me. Speer also list there their 85 grain SPBT at .404 and the 100 grain at .430, all of which have a better listed BC than the 95 grain Nosler BT.
Many people apparently still don't understand that even if a bullet will group in a certain twist, if it isn't "overstabilized" by a minimum of a 1.5 factor (1.0 is enough to remain point-on) then BC is reduced by up to 15%. Thus you may have a bullet with a listed BC of .450 but the functional BC can be as low as .380-something.

BC isn't a hard and fast figure, and often another bullet designed to fully stabilize in a certain amount of twist but a lower listed BC may work just as well, because it retains all of of its BC from that twist.

One of the other reasons I suggested the possibility of the 95 Ballistic Tip is I know it's a sure-enough elk bullet, because the guy who designed it for Nosler killed several with it, including mature bulls.

But whatever.
John,

I'll lay in a stock of the 95 BT.

Thanks!
Originally Posted by shrapnel
Originally Posted by David_Walter
And I hunt at only 1,000 feet


Who cares what you shoot, I just want to find a place to shoot elk at less than 1000 feet in elevation...


Me too!
I thought this was a place for open discussions and shared knowledge, but feel free to correct me if I'm wrong? I was just simply listing bullets that all had a better BC than the 95 grain ballistic tip, that are supposed to work in the more traditional 10 twist barrels. I never once said that the 95 grain BT was a bad choice.

Yes they all don't have a stability factor of 1.5 a the OP's elevation of 500 feet ASL, but even with the reduced BC they still have a higher BC than the 95 grain ballistic tip. The Berger HC and Sierra GK both have a stability factor of 1.36 and BC is only reduced by 4%, that isn't anywhere close to 15%. The Speer bullets both have a stability factor of 1.5 and both beat the 95 grain NBT in BC on paper. The only way to tell for sure what the OP will get for BC is to shoot them at range and do the math, we can only point him towards bullets.

Now as far as the bullets ability to kill elk, I'm sure they all will though I think the OP would be better served by a 6.5 caliber of similar case capacity. However, I'll defer your knowledge on the NBT being superior for the job when it comes to 6mm's on elk. Though I've seen my share of elk killed with 100 grain Core-Lokt/PP .243 factory fodder from a relative of mine, which leads me to believe that most bullets put in the proper location equal dead elk. Though admittedly none farther out than about 250 yards.

Originally Posted by Mule Deer


But whatever.

Originally Posted by navlav8r
Originally Posted by shrapnel
Originally Posted by David_Walter
And I hunt at only 1,000 feet


Who cares what you shoot, I just want to find a place to shoot elk at less than 1000 feet in elevation...


Me too!


Most of my elk hunting is done at less than 250 feet above sea level. smile
The 95 gr BT's and Game Kings have always worked good for me but I am spoiled over the 165, 168 gr( any bullet but SST's) ,30 cal bang flops, and 25 cal( 110 accubonds) rodeo buck kick and go down, 264 win mag( 130 gr accubonds) drop in tracks to deer hunt with 243 any more... Not saying its not a whitetail killer, I just own 10 more guns that do a quicker , bang flop job! I do love my pre 64 Varminter and 70 gr BTs on varmints!! v best winpoor
i won the first 1000 yard match i shot in with a 1-12 twist .243 hart barrel. i shot a mixture of 88 grain bergers and 87 grain hornady bthp (both moly) and a stout load of I4064. the 87 berger and 90 scenar were not available then. i believe barrel quality helped me against others shooting factory barrels.
sorry if i was off in my reply there. even though i have had great success with the .243. on deer,antelope and coyotes; elk and bear gave me a good excuse to get some 30-06s and 7mms.
David,

You should simply try some bullets that you'd like to shoot and see for yourself. I have a 10 twist and shoot the 105 A-Max at 3060. The calculators say it has "marginal stability" at the altitudes it will be shot and shows also a slight decrease in BC through the 10 twist.

First hand experience shooting it tells me that it works fine. Well, actually better than "fine"...


[Linked Image]

[Linked Image]



710 yards

[Linked Image]


760 yards

[Linked Image]



You'll never know unless you give it a go...

Have you thought about this bullet:

http://www.hornady.com/store/6mm-.243-105-GR-BTHP-Match/


It is supposed to stabilize in a 10 twist and reports I have seen say it does well on game despite the manufacturer's admonition about shooting game with "match" bullets.
Have some I'll try.
WTF is an elk?





Travis
Originally Posted by deflave
WTF is an elk?





Travis


Rabbit with antlers.
Unicorn with branched headgear.
[Linked Image]
Anti Palin, pro Obama, John Cleese in drag
95g Partition is right at home with a 10" twist, 43g of IMR 4350 with a win primer

85g triple shock, max load of R#19 with a Win primer, also.

Your house would not hold the deer and antelope we killed with the 95g partition, no kidding. Big Kansas and Nebraska deer that went over 200 lbs and yardage out to 360, NONE ever went over 10 yards. With the 95g partition, quartering shots coming and going is no problem as the bullet plows through shoulder blades and ribs on the quartering shots, always exiting. Wound channels are massive with good blood trails.

Blood trails with the 85g Tripple shock with the max load of R#19 were never seen as all deer were laying in their tracks.

I can't say anything bad about the other bullets mentioned, you just have to use the 95g Partition to see what I am talking about. The 95 at 3100+ causes massive tissue distruction, lungs and heart are just mush, nothing left of them, plus the complete penetration and blood loss.

I think that the new R#26 would shoot the 95's at 3300 with accuracy.

Friends used the 243 with the 95's on 450 lb cow elk in Az with no problems while I held the mules.
Dave, If Elk is on the menu I'd go bigger.

I've pulled fulled heald over.243 Partitions out of elk I've killed with a bigger gun.

If however, I was looking to optimize a load for the .243 for game up to Mule Deer, I'd start with the 95gr NBT...
Originally Posted by Mule Deer
Many people apparently still don't understand that even if a bullet will group in a certain twist, if it isn't "overstabilized" by a minimum of a 1.5 factor (1.0 is enough to remain point-on) then BC is reduced by up to 15%. Thus you may have a bullet with a listed BC of .450 but the functional BC can be as low as .380-something.

BC isn't a hard and fast figure, and often another bullet designed to fully stabilize in a certain amount of twist but a lower listed BC may work just as well, because it retains all of of its BC from that twist.

One of the other reasons I suggested the possibility of the 95 Ballistic Tip is I know it's a sure-enough elk bullet, because the guy who designed it for Nosler killed several with it, including mature bulls.

But whatever.


So what's the explanation for reduced BC? I understand that bullet wobble is maximum as the bullet leaves the muzzle and some barrels induce more wobble than others, but generally wobble dampens out as the bullet travels downrange. I've heard this dampening out effect referred to as the bullet going to sleep and that this happens within the first 100 to 150 yards. Is that what you are talking about or something else that's independent of range?
The reduced BC has to do with the bullet's epicyclic motion. There are two arms to this motion- the nutation arm and the precession arm. The nutation arm is mostly damped out by 100 yards, but the precession arm typically remains constant, or it may decrease or increase as the bullet flies down range, depending on bullet mass and aerodynamic properties, and twist rate. It is this precession arm in which we see less stabilized projectiles exhibit greater yaw and pitch, regardless of distance. When gyroscopic stability is insufficient to overcome dynamic stability, the bullet settles into a greater limit cycle yaw angle, and BC suffers.

Typically for every 0.1 factor decrease between 1.0 and 1.5 using the Miller stability formula, you can expect about a 3% decrease in BC value.
...shoot the Fuggin' thing and see how it works.


All the Gibbery Jab means Crap if the bullet shoots at range.

laugh
Barrels that are supposedly "10" twist, aren't always exactly 10 twist. You should try the bullet and see.

Nothing to lose
Many thanks for the explanation. It seems this effect would be hard to detect in the field particularly given few would inadvertently find themselves in a worst case 1.0 stability situation.

For anyone wanting to accurately measure BC, proper stability is yet another factor that needs to be taken into account.
On another forum I read a thread about stabilizing a Berger bullet in a 10" twist 243.

There were lots of posts and they seemed to alternate between:
1) Works great for me
2) I tried and it was terrible

Myself, I put 75 gr Vmax in a 14" twist 6mmBR and shot at 0.2 moa 3 shot group and a 3 shot group of keyholes. I will mark that one down as marginal.
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