Nosler Partition accuracy???

H

hoofmender

New member
Just want to ask this large knowledge pool if anyone has been having accuracy issues with recently produced Nosler Partitions? I should say I have loaded and trusted these bullets for 5 decades with easily obtained MOA accuracy in most cases...
This year I acquired some fresh .257 Nosler 115gr Partitions that I intended to work up a load for my usually tack driving custom 257 Ackley Improved. After several attempts with everything well over 2 MOA ,(shotgun patterns), I happened to weigh a box of them...Holy ████! The spread from the lightest to the heaviest was 3.8 gr!!!! Weighing all I had and segregating by .5 gr increments, matched batches were better but still flirted with barely MOA groups.... with Speer Hot Cores or Hornady Interbonds, this rifle is always around 1/2 MOA... Any similar experiances? Thanks, DW
 
The Nosler Partition is a little funny in that the copper in the center pushes the center of gravity forward, increasing the transverse moment of inertia. That results in them being a little more demanding of having a fast enough twist to be well stabilized. The stability estimator at the JBM site suggests that without that copper in the middle, it should be stable at 2900 fps with your twist rate, but would fall below optimum at the freezing point and would be below the stability factor of 1.3 that Sierra (I don't know about Nosler) considers adequate for hunting accuracy. Add in the effect of the lower density copper partition just behind the CG and it could be marginal with a 10" even at 60°F. I'd have to measure the moments of inertia of the bullet to give you a certain answer.

IF you were willing to waste the money, you could prove this by getting both the 100-grain and the 120-grain partitions. The former should stabilize in a 10" twist, but the latter should do worse.

As to the weight variation, that is surprising in a modern bullet. It will mean the bullets came off different sets of tooling. You might contact Nosler about it. Maybe they will replace your box with some 100-grain Partitions that your gun will like better?

Please note the red block in your post. This is a family-friendly forum, and you used a word on the prohibited list. Please avoid that in the future.
 
Thanks for the info.. very interesting..... the twist rate in this particular barrel is 1 in 9, so that shouldn't be a factor.... but the location of the copper is an interesting thought as to why the Partitions don't seem to be as accurate as some others with everything else being equal..... it's all great fun.....

sorry about the red block...it's a word you can hear on the evening news about every night???DW
 
Yeah, I know. Periodically we review the list and have taken a number of words off of it. That one will probably go eventually.

You are correct that the 9" twist handles that bullet's dimensions (I have a length of 1.145" from the JBM list; does that match yours?). But I can't say how much difference the partition is making without measuring its moments of inertia and going through the long calculation for stability. Since I don't have a .257 caliber gun or any Partitions on hand, I can't make that determination.

If you feel inclined to do it, you can make a torsion pendulum of the type used to determine the moment of inertia of a model airplane in this paper. You need both the transverse and axial moments, so one would be determined with the bullet lying on its side and the other with it standing upright on the block. I use a small tray cut out of a tin can and a couple of very fine bits of tungsten wire. You basically find the MOI of the block or tray by itself first, then with the bullet in the two positions so you can find the difference from that of the block alone. Long, skinny wire probably at least six feet long will be more accurate to time the oscillations than something shorter. If you give me that information, I can do the formal stability calculation.

On the other hand, you've got weight inconsistency which will mean inconsistency in the moments of inertia, so you could also skip the calculations and just sort by matching moments of inertia. Slow, but doable.
 
I have not used Partitions below .277 caliber. But I have used them in .270Win, 7mm, .30-06, .338-06 for years. I have 4 rounds of .338-06 left and I have 35 rounds of .270 left, then I am switching.

When I bought my .338-06, I shot a 3/8" 100 yard, 3 shot group with the Partitions out of the gate. When I loaded up the last batch, bought in 2019, same everything, I was over an inch at 100 yards. I thought it was me, then my scope and went through all kinds of iterations trying to figure out what was going on. Even hunted with a different rifle for Elk in 2019. Well, it was the Partitions, thus the switch. I have suspicions as to why they are worse, but I'd rather not speculate. I shot more rounds trying to figure out what was wrong than in the preceding 8 years from that rifle. After 70ish rounds, I finally got to the bullets and found inconsistencies not just in weight, but in the cg and concentricity. No, I did not bother to call Nosler, and I have about 5 bullets to test in .338-06 this spring. Already found a better bullet for the other calibers, and yes, some are Nosler's, but newer designs.
 
… After several attempts with everything well over 2 MOA ,(shotgun patterns)…
Click to expand...

A few years ago, one moa was considered the minimum accuracy required to shoot two-pound prairie dogs. Now - suddenly - you need that level of accuracy to kill a 150-pound deer….or do you? The internet and the lies perpetrated by many many posters seem to have changed that limit to less than moa. All of which is pretty meaningless in the field from field positions. I’m all for improving accuracy, but how many hunters actually fill their tags with a 400 yard shot?

The OP does have a legit concern about bullet quality, we do expect more and should receive it in today’s world. But a deer rifle doesn’t need to meet varmint rifle standards for the vast majority of hunters.



.
 
I use Noslers in my 7mm-08 ans 7mm mag
In the 7-08 it is 140
In the 7mm mag it is 160
the BTs are a tad more accurate in both, the partitions are still at 1MOA or better; for deer/elk, that is a no brainer
 
I only use them in my 223, but that was in the first barrel, and I had an accurate load. With the new barrel, I haven’t tried them yet. As for potential accuracy, I don’t think they’ll ever equal the Ballistic Tip for accuracy, but then again, we don’t shoot Partitions for top accuracy.
 
My impression is that the partition is "fading away" simply because they are expensive to make. The ammo I've loaded with .270 on up has been amazingly accurate in the Weatherby's I've shot them in--as has been Weatherby's own factory ammo that uses them--but regrettably it appears Weatherby is dropping the partitions from their line gradually. I usually zero them for 200 to 300 hundred yards.
 
I've used Partitions in 7mm and 6.5 and have had similar results. The 150gr 7mm printed 1.5 to 2 inches and the 100 and 125 6.5 were about the same. Hornady, Interlock, Interbond, and GMX were all tack drivers. After killing a nice Buck this year with a marginally placed 154gr Interbond, I'll stick with Hornady. The Interbond is a devastating design. I was not able to recover it, but it shattered the left "elbow" joint on the way out after exploding the heart and part of the lungs from a brisket hit.
 
I got 2 boxes of the 25 caliber 120gr Partition blems from Shooters Pro Shop when they were available.
Using them in my Savage 111 with 1:10 E.R. Shaw 24" barrel in 257 Roberts AI.

I didn't weigh them, but noticed a few with bent tips. About 45° or better.

Using PPU 7X57 Mauser brass run through a 257 Roberts f/l die, then fireformed.
Alliant RL19 is giving me 5 shot groups close to an inch at 200 meters.
1,3/4" at 300 yards.

Yours isn't the first i've heard of accuracy issues with the Partitions.
They've been doing well by me though.

The regular Accubonds are another story!
Just can't get those to group no matter what caliber or cartridge!
 
Thanks so much for all the feedback...I sure appreciate it......

And, nope.... don't need MOA accuracy to punch a deer's lungs out at 100 yards..... I just like doing it..... just somethings about working at the loading bench, thinking you've figured something out and then see it happen at when you shoot 'em! Now, where I live in Southeastern Arizona, cross canyon shots routinely present themselves in the 400 yard + range, usually accompanied by 1-20 mile per hour winds.... THAT'S when i want that magical 1/2MOA!

I think I'm done with Partitions.... not sure what they've changed, but it sounds like I'm not the only one that has noticed a downhill slide in their quality lately.... The info on the interbonds above is welcome as those that I have loaded in several calibers have shot great! I have had great luck with Speer Hot Cores and Gold Dots as well..... those that I've recovered from my water trap have looked pretty good as well...

Thanks again, DW
 
Originally Posted by TX Nimrod View Post
"I’m all for improving accuracy, but how many hunters actually fill their tags with a 400 yard shot?"

"So why troll someone else's post?"

I don't think it was trolling the question. Years back, 1973 IIRC I had to take a shot at a deer my hunting partner had wounded. Shot from where I was standing was 426 paces. Call it conservatively 400+ yards. Rifle was a Remington 660 in .308 Win. that struggled to do 1.25" at 100 yards. probably some skill with a little luck added. Bullet was a 150 gr. Sierra Pro-hunter.

About 12 years ago I had to take a shot at an elk at what was lasered at 530 yards. Easy shot really as it was in a comfortable sitting position and had practiced to 500 meter on my clubs silhouette range. Rifle was a Winchester M70 in .300 Win. mag that was a .75" gun on average. The area hunted is known for some very long ranger shots so I was prepared for the shot with several months practice from various shooting positions. Bullet was a200 gr. Speer Hot-core.


I admit most of my shots at game have been on the order of 200 to 250 yards or less, mostly less. Bullet type on the mentioned was irrelevant, being off topic.
Paul B.

On the accuracy of Nosler Partitions, what little I have used them, accurarcy has ranger from MOA to slightly less in the rifles I used them.
 
Sorry to hear that about that 115gr Partition, I have been shooting it for about 30yrs from my 25-06. They have always seemed to hold around 1/2 - 3/4" at 200yds. Made that rifle a real pleasure to hunt with. It has always hit where I aimed or close enough it didn't matter out to 400yds.

I built a 25-06 AI a few years back and figured I'd use them in it. Funny thing was I had purchased some 120gr Core Lokts and while fire forming and working up loads found they were shooting tighter groups. They also have done a remarkable job on game at ranges from as close as 30ft out to 450yds.

I completely understand trying the Hornady and Speer. I have gradually started moving that way as well in several calibers. I had high hopes of Nosler bringing out the Accubond or Hornady the Interbond in a 115gr, but both went with the 110gr instead. I know their reasoning was it stabilizes better, but they said the same about a 115gr BT years ago and it's one of their best selling in 25 caliber.

Good luck with your endeavor and hope you find something that works for you.
 
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