I had a chance to shoot over my new chrono today, and I noticed the IMR 4350 shot great around 2800 fps. The varget shot good around 2800 fps. If I was to try a different powder, would it most likely shoot good around the same 2800fps? Thanks!!
- Thread starter myownman
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well w/o knowing the cartrige, bullet, load is hard to know. Might be able to shoot a faster powder like H4895 or R15?
W.o more details will be hard to help you.
W.o more details will be hard to help you.
7-08 24" barrel 150 SMK's. lapua brass. It was a general question. I'm not looking to change powders. My question is, even with a faster powder, would I still be looking for the same muzzle velocity? I understand that there may be multiple nodes. But with a different powder would one most likely see a node around the same MV? Thanks.
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Just getting into this node stuff but it would seem to me that the velocity of the bullet traveling down the length of the barrel would have the biggest "impact" on changing the location of the node with regard to barrel harmonics.
I'm guessing that pressure curves could have an effect but I would think that the bullet itself would have the most.
My 308 shoots 4064 and 4895 EXACTLY (and quite well, thank you) the same when the velocities are matched.
I'm guessing that pressure curves could have an effect but I would think that the bullet itself would have the most.
My 308 shoots 4064 and 4895 EXACTLY (and quite well, thank you) the same when the velocities are matched.
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Not exactly.
What you are looking for is the same barrel time.
A different burn rates can develop different accelerations. So with the same muzzle velocity, one load can have a different barrel time than another.
One load could have the bullet at MV half way down the barrel, versus another load that accelerates linearly to just reach MV at the muzzle. The first is not likely, but to illustrate how the same MV can have a different barrel time.
What you are looking for is the same barrel time.
A different burn rates can develop different accelerations. So with the same muzzle velocity, one load can have a different barrel time than another.
One load could have the bullet at MV half way down the barrel, versus another load that accelerates linearly to just reach MV at the muzzle. The first is not likely, but to illustrate how the same MV can have a different barrel time.
A general question? I don't understand the curiosity because, (opinion) it's not especially important? You want a reasonable velocity but different powders perform differently and the main thing is consistent velocities and consistent accuracy. Expecting "same" velocity is <shrug> not what you should be concerned with. Not only that, but your velocities will change, based/due to ambient temperature. BB
I'm not trying to reach the same muzzle velocity with each different powder. While shooting over the chrono, I noticed I had good accuracy around the same MV with three different powders. Granted two were pretty close burn rate H4350/IMR 4350. Which led me to my general question. I wasn't asking about just my rifle.
Faster burn leads to faster acceleration all other things being equal.
A faster powder has the potential to move the same projectile at faster velocity in the same barrel but also might create an early spike in pressure or even over pressure.
Forget about the nodes for a second. What you want is consistency. So it is not a matter only of speed but how that speed is achieved and if the speed can be repeated over an over.
A key factor of this is consistent starting pressure. So not only the powder but the primer, neck and crimp have a role on it too. Changing one thing (like powders) does not guarantee
all other components in the internal ballistics will behave the same or in a proportional way.
This is all very hard to predict and the only good way to find out is by testing. That is why shooters and manufactures spend so much time testing their components.
So if you have something in mind, try it and make sure you follow all the necessary safety steps.
A faster powder has the potential to move the same projectile at faster velocity in the same barrel but also might create an early spike in pressure or even over pressure.
Forget about the nodes for a second. What you want is consistency. So it is not a matter only of speed but how that speed is achieved and if the speed can be repeated over an over.
A key factor of this is consistent starting pressure. So not only the powder but the primer, neck and crimp have a role on it too. Changing one thing (like powders) does not guarantee
all other components in the internal ballistics will behave the same or in a proportional way.
This is all very hard to predict and the only good way to find out is by testing. That is why shooters and manufactures spend so much time testing their components.
So if you have something in mind, try it and make sure you follow all the necessary safety steps.
It can happen but you cannot assume this always works like this. Only testing can verify that.
