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Is bullet speed node, the same say rifle to rife?

NC/Br Shooter

Silver $$ Contributor
As the title asks, that's my question.
Say, any of you find a speed a particular bullet likes for your rifle,
Shouldn't I be able to take that same bullet and load it to the same speed and get similar results?
In this case, I'm looking at 90 Berger bt.
These bullets shoot amazing in my 6bra, from 28, 30, 31, 31.7. Grains of powder.
I just bought a chrograph today.
Brand new Caldwell one. It's cheap, kinda, but I just want some reference so I can quit doing these ocw tests.
Any comment, suggestions welcome
 
Every barrel is individual, because internal stresses created during manufacture are beyond outside control. Chances are that results from another barrel of the same shape and make are similar. But there is no guarantee. In the end, every rifle has its individual zero and individual dispersion.
 
Well. Depends on the level of accuracy and how similar the two rifles are.
I can say that if you take two rifles that are the same - similar actions, similar stocks, similar barrels [especially the same length] - an accurate load [say 1/2 MOA] in one will probably have similar accuracy in the other.

Not sure what happens below 1/2 MOA.
 
Using a 68 Hornady in .223 loads, my service rifle & my match, hit that node at the same charge of 8208XBR.......but go to a 69 SMK and there different......
OK, this is what I had I'm mind. Thanks, I do have friend who has same barrel. Running same powder. We are not sharing load data.
I figured I'd do a few more ocw tests running the chronograph to see how far apart nodes are.
Generally, how wide would accuracy node be in 90 grain burger, 6bra, rl15, ? Seems I get best groups 30 to 31 grains, after 31, iv not been able to get a one inch group past 250yards
 
Typically for the PRS level of accuracy requirements, 0.3-0.5gr is average for a velocity node. Depends on cartridge size, barrel length, etc.

I personally believe that bullets, regardless of shape, weight, caliber, etc. all like to leave barrels at the same certain speeds. There is much more to accurate loading than speed though and these other factors need to be accounted for. But in the end, match winning loads tend to end up with “predictable” muzzle velocities. Too consistently to be by chance.
 
Wait.
There's several velocities at which a given barrel and load are accurate [i.e., .4 - .5 MOA]. Are you saying you think that the set of velocities that are accurate in a given barrel and load are the same set of velocities in other barrel lengths with the same load? For example, the set of velocities that are accurate in a 16" barrel are very close to the set of velocities in a 30" barrel?
 
The node is associated with barrel time, of which velocity is one component. Obviously barrel length is another. These are primarily factors which relate to tuning the bullet exit time with the barrel's vibration harmonics. For a given powder and bullet I have found the charge weight is a better determinate than velocity, but certainly not a rule.
 
The node is associated with barrel time, of which velocity is one component. Obviously barrel length is another. These are primarily factors which relate to tuning the bullet exit time with the barrel's vibration harmonics. For a given powder and bullet I have found the charge weight is a better determinate than velocity, but certainly not a rule.

I have found many similar nodes using completely different powders on the same bullet in many rifles with varying barrel lengths when the given bullet hits in the area of a certain speed. Even when using the same powder, the charge weights will vary with different barrel lengths, bore sizes, and twist rates to hit the velocity nodes. Of course there are no guarantees there either
 
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This is what Im talking about! These last two or three opinions I find interesting.
Myself, I use charge weight,then seating depth to find my best combination. Latly, Iv been interested in finding my lowest node I could use for 105 class 6mn pills, in hope that I can find more consistency. 200 yd max.
Is 2700 fps the lower node about for 6bra 105s?
 
Wait.
There's several velocities at which a given barrel and load are accurate [i.e., .4 - .5 MOA]. Are you saying you think that the set of velocities that are accurate in a given barrel and load are the same set of velocities in other barrel lengths with the same load? For example, the set of velocities that are accurate in a 16" barrel are very close to the set of velocities in a 30" barrel?
My theory is that a bullet leaving a barrel is a form of atmospheric entry. The effects of the atmosphere being negligeable in comparison to the friction in the barrel. I actually prefer to speak of nodes as being the points between turbulent zones.

Almost all bullets of varying profiles, weights, diameters, manufacturer, etc. seem to have relative stability in certain velocity nodes. These nodes seem to be consistent across the board, with slight variation from rifle to rifle. With the current consensus that B.C. and recoil management are just as important as speed, competitors no longer look in the upper ranges of speed for advantage. I personally don’t believe that accuracy wanes, so much as rifle handling skills do, especially on larger calibers. The accepted method is now shoot at your 2650-2900 node of choice. Adjust cartridge recipe accordingly to get into that zone.

This is my personal theory, I have no means to test or prove it either way. Anecdotally there are just too many cartridges pushing too many different projectiles that seem to “settle” at the same speeds, consistently. Some can achieve the next “node”, while others cannot. It seems that one can estimate within 10-15fps of where a rifle will shoot, almost guaranteed. I’m not saying the absolute best node, just that one will be there.
 
Wait.
There's several velocities at which a given barrel and load are accurate [i.e., .4 - .5 MOA]. Are you saying you think that the set of velocities that are accurate in a given barrel and load are the same set of velocities in other barrel lengths with the same load? For example, the set of velocities that are accurate in a 16" barrel are very close to the set of velocities in a 30" barrel?
I think that if you were to use a combination that equaled the 16” velocity from the 30” barrel, using the same bullet, then yes. Obviously it would not be optimal, velocity wise, and would leave roughly 400fps on the table. It’s a very complex dynamic and I believe almost impossible to prove
 
On the surface, one might expect that two similar, if not almost identical, rifles would exhibit very similar tuned loads if using the exact same reloading components. That seems like a very reasonable conclusion to make, right up until you encounter two similar rifles for which the tune is noticeably different. It is difficult enough to anticipate with any great accuracy the effects of reloading component Lot-to-Lot variance such as powder burn rates, case volume, etc., let alone the potential differences between two barrels. Because we can empirically tune a given rifle and the fact that one individual will usually be consistent with their selected tuning approach from rifle to rifle, the best bet is simply to determine what the rifle wants for an optimized load. If that load happens to be the same as an optimized load for a similar rifle, great. If not, it won't matter because the two rifles were each tuned individually. If the idea is to use someone else's developed load for a similar rifle as a starting point for your own load development, there is nothing wrong with that as it can save time, barrel life, and reloading components. But you want to be aware that it is only a starting point, and you still need to cover charge weight and seating depth windows that are sufficiently wide, especially if re-creating the exact same load doesn't seem to work as well as it did in the other rifle.

I've had multiple barrels on at least three different rifles set up very similarly where the charge weight and seating depths for each have ended up very close over a period of several years, meaning with different Lot#s of powder, bullets, and brass (each from the same manufacturer, i.e. Varget/Berger/Lapua). So it certainly can happen. Likewise, if you look around at what F-TR shooters are commonly using in .308 Win, you will find that many of their loads are almost superimposable. For example, the use of a 30" barrel, Varget, 200.20X bullet, Lapua brass, yielding ~2640-2660 fps is a common recipe for success in F-TR. But it's not written in stone that it has to be that way. Variance in powder burn rate, effective case volume, or even bullet diameter can cause noticeable changes to have to be made to optimize a given load. The less stringent the precision requirement, the more often it will likely be that the same load appears to work well in two very similar rifles. If you're striving for the utmost in precision, it may be more noticeable that subtle, or even not-so-subtle changes in the load are necessary to get two similar rifles shooting optimally.
 
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You wanna go crazy with this "node",velocity uniformity thing
Shoot a .222 Remington BR gun with 1-14 twist with 50g bullets.I had two that shot sub .2 much of the time and the standard deviations in the high teens to low 20's ! Yuk.
 

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