Reloading assumptions
- Thread starter TriggR
- Start date
Marco Califo
New member
700X is a powder formerly from IMR. Hodgdon now carries 700X in their lineup. 700X (and 800X IIRC) were "transfered or traded" from the IMR brand to a Hodgdon branded powder. No discontinuance.
Marco Califo
New member
Pressure does not increase as the bullet travel down the barrel. Barrel length and pressure are not related at all.
Your knowledge of the physics involved is flawed. Read a reloading manual.
When You ASSUME
You make an ASS out of U and ME.
Your knowledge of the physics involved is flawed. Read a reloading manual.
When You ASSUME
You make an ASS out of U and ME.
It has been answered that shorter barrels cannot take more charge weight safely. It has been answered that this is because the peak pressure occurs very early in the barrel travel distance.
What is velocity the result of? That has been answered, but less clearly. At the back of the bullet the pressure due to the powder burning is exerting a force on the bullet. On the bullet, the barrel exerts an engraving force. The pressure building and maintaining high pressure for a longer period is what makes velocity. Essentially the integral of the pressure curve over the barrel time(distance)
So, your short barrel has low velocity due to less barrel time. The fix is a longer barrel or more engraving force. More engraving force will drive up the start pressures though, so I would not recommend experimenting there. It also seems to not improve velocity much.
Going to a powder like Longshot which have a longer burn curve is your answer, but is not where you want to go.
Something like 700x is a nice “puff” powder, but often has low velocities. That is what it is.
BTW, 700X is also known for extreme charge variation in volume measured loads. Be cautious.
Quickload can be a good teacher, for the person whom wants to really dive into the why of reloading.
What is velocity the result of? That has been answered, but less clearly. At the back of the bullet the pressure due to the powder burning is exerting a force on the bullet. On the bullet, the barrel exerts an engraving force. The pressure building and maintaining high pressure for a longer period is what makes velocity. Essentially the integral of the pressure curve over the barrel time(distance)
So, your short barrel has low velocity due to less barrel time. The fix is a longer barrel or more engraving force. More engraving force will drive up the start pressures though, so I would not recommend experimenting there. It also seems to not improve velocity much.
Going to a powder like Longshot which have a longer burn curve is your answer, but is not where you want to go.
Something like 700x is a nice “puff” powder, but often has low velocities. That is what it is.
BTW, 700X is also known for extreme charge variation in volume measured loads. Be cautious.
Quickload can be a good teacher, for the person whom wants to really dive into the why of reloading.
jetinteriorguy
New member
One of the best ways to blow up a gun is to start making assumptions when hand loading.
reynolds357
New member
More engraving force does not necessarily mean more velocity. Past a peak point, it means less velocity. Less engraving force is a more practical way to get more velocity. When I first started messing with moly coated barrels shooting lubralox coated bullets, I found this out. My 6x284 lost almost 200 fps using the max load I had reached for uncoated barrel and uncoated bullet. I was then able to go up on powder to the point I was getting 200+ fps over the old established maximum load. I finally quit messing with Moly because the end result is not worth the effort.
reynolds357
New member
You know what "assume" does.
Marco Califo
New member
Then you have an old container. What was the manufacture date? Lot #?
Hi-Skor 700x Smokeless Powder 4 Lbs
Hodgdon # 7004 | Item # 034-7004
It is out of stock at www.Midsouthshooterssupply.com.
I am "most certain" you are NOT cognitively processing the answers to your questions.
Hi-Skor 700x Smokeless Powder 4 Lbs
Hodgdon # 7004 | Item # 034-7004
It is out of stock at www.Midsouthshooterssupply.com.
I am "most certain" you are NOT cognitively processing the answers to your questions.
Okay so I think I've got a good handle on it $30,000 PSI for example is in the chamber as the bullet travels down the barrel the pressure must drop because there's more area to fill and continues to drop as more area is made available until exiting the barrel so the pressure in the chamber and Barrel is always much greater than the 14.7 PSI on the outside of the barrel thus it's continuously being pushed until exiting I would like to thank those who answered seriously and to the few that were mainly just mean you guys need to take a break from The Forum
Glad we could help you get it figured out. Happy loading.
Now, to really boggle your mind, many modern smokeless powders are "progressive burning". Meaning the burning rate of the powder changes as the pressure changes.
As the bullet moves down the barrel, there is more space for the powder gas to fill. The rate this happens is the expansion ratio. Modern progressive powders are formulated to burn in such a way that this expanding area is filled by powder gas at (as close as can be attained) full pressure. Matters more with rifles than handguns, but the principle applies to both.
Even the "weakest" rounds push their bullets with several TONS of pressure per square inch. High pressure rounds can push with a couple dozen tons of pressure on the base of the bullet. So, yes, it scoots right along, overcoming the resistance of the rifling and reaching speeds of hundreds or thousands of feet per second.
As the bullet moves down the barrel, there is more space for the powder gas to fill. The rate this happens is the expansion ratio. Modern progressive powders are formulated to burn in such a way that this expanding area is filled by powder gas at (as close as can be attained) full pressure. Matters more with rifles than handguns, but the principle applies to both.
Even the "weakest" rounds push their bullets with several TONS of pressure per square inch. High pressure rounds can push with a couple dozen tons of pressure on the base of the bullet. So, yes, it scoots right along, overcoming the resistance of the rifling and reaching speeds of hundreds or thousands of feet per second.
reynolds357
New member
Yes, but from your post it sounds like this phenomena is occurring an entire 26". It is in actuality done In less than 6 inches unless you are using a powder so slow that it is out of burn rate range of cartridge. Kind of like one day many years ago when I used to drink I loaded some 357 mag with RL25. 90 % of the powder got "puked". It probably did reach peak pressure close to end of barrel.
TriggR, most of the folks here have decades of handloading under their belt, some half a century. We all appreciate what your goal is, however most of us have been there and know better.
I've been handloading in general since the early 70's and started on 10mm in the mid 80's. I have run from mild to wild with it and MUCH prefer the lesser of the wild. Both of the 10's I now have sport 7" barrels. The reason why is I hunt with them and the longer sight radius and added velocities make them more efficient.
As mentioned pressure isn't going to get you velocity, burn rate is, however to take advantage of it, you need barrel length. I understand you have a copious amount of powder you want to use up. I can only offer up suggestions or opinions, but I would honestly say to use the 700 for practice loads, maybe pick up some AA-7 or AA-9 , and see where they get you on your velocity. I get more than enough velocity from #9 with nominal pressure and within book loads. It is and has been my preferred powder almost since I started loading this caliber.
If there was something magic out there that did just want you wanted, it wouldn't be available. It would be like H4350 or Varget, everyone would want it.
Hope this helps. Not trying to be the bearer of bad news but sometimes things just are what they are.
I've been handloading in general since the early 70's and started on 10mm in the mid 80's. I have run from mild to wild with it and MUCH prefer the lesser of the wild. Both of the 10's I now have sport 7" barrels. The reason why is I hunt with them and the longer sight radius and added velocities make them more efficient.
As mentioned pressure isn't going to get you velocity, burn rate is, however to take advantage of it, you need barrel length. I understand you have a copious amount of powder you want to use up. I can only offer up suggestions or opinions, but I would honestly say to use the 700 for practice loads, maybe pick up some AA-7 or AA-9 , and see where they get you on your velocity. I get more than enough velocity from #9 with nominal pressure and within book loads. It is and has been my preferred powder almost since I started loading this caliber.
If there was something magic out there that did just want you wanted, it wouldn't be available. It would be like H4350 or Varget, everyone would want it.
Hope this helps. Not trying to be the bearer of bad news but sometimes things just are what they are.