Speed gain

[fvalmostthere]

Just saw a 35fps increase in my speeds while load testing 3 different bullets. Barrel is right at the 250 shot mark, so I am assuming it's a barrel break in thing. What is the protocol here? Drop back down and run another ladder up to make sure I'm still in the middle of that mode?

 

[47guy]

if its still shooting small groups with the current id load 3-5 rounds at .2g higher and shoot a group if its a small group stick to your current load...if it opens up enough to worry about then id load 3-5 rounds at .4g lower and .2g lower and shoot them for groups one of these two loads will drop you back down into your speed node.

 

[Deleted member 10043]

Or you can just keep shooting. Speed, spead, speed. So-called nodes are generally too slow or unshootable high. The former puts you in an unnecessary wind handicap. I see too many people wasting time opting for a one caliber difference in non-statistical group size difference that even if true has no bearing down range and shooting too slow putting themselves at a disadvantage. A node is psychological. It's between your ears and has little to do with ammo complementing the rifle in addition to the shooter who is nothing more than a node killer even if it does exist. In my opinion node work up is still in the hypothesis stage with a long way to go before it can be called a theory.

 

[ken4570tc in WY]

Or you can just keep shooting. Speed, spead, speed. So-called nodes are generally too slow or unshootable high. The former puts you in an unnecessary wind handicap. I see too many people wasting time opting for a one caliber difference in non-statistical group size difference that even if true has no bearing down range and shooting too slow putting themselves at a disadvantage. A node is psychological. It's between your ears and has little to do with ammo complementing the rifle in addition to the shooter who is nothing more than a node killer even if it does exist. In my opinion node work up is still in the hypothesis stage with a long way to go before it can be called a theory.

Culpepper,

I know for sure your quote is not genuine but I will take your comment about nodes into account as I'll be starting load development soon for my .243 RPR. I'd like to prove nodes are a bunch of BS or that they're not. I'll let you know what I find.

 

[fvalmostthere]

if its still shooting small groups with the current id load 3-5 rounds at .2g higher and shoot a group if its a small group stick to your current load...if it opens up enough to worry about then id load 3-5 rounds at .4g lower and .2g lower and shoot them for groups one of these two loads will drop you back down into your speed node.

Thanks, that was kind of my plan, shoot them and see if they work and if not work back down a bit. The 123 scenars and 130 hybrids grouped fine even with the speed increase during seating depth testing but the 140 hybrids were all over the place. I have never shot groups that bad, it was like a surprise everytime I fired I got to say where did that one go? I will probably work back up with the 140s.

 

[Greg Langelius *]

For the 140's seating depth may be at issue (I.e. They may be right at a tip-over point where some are in the rifling and some are not due to ogive variations, this can happen with longer ogive curves); try seating them shorter in .010" increments.

Greg

 

[fvalmostthere]

That was when they went to crap was during seating depth testing. I am using 42.8gr of H4350.

My first test was a 1 shot ladder in .5 increments. (42.5 - 2790 and 43 - 2806)
My second test was a 3 shot more concentrated ladder in .3 increments (42.6 - 2809 and 42.9 - 2814 average)
My third test was a 5 shot in .2 (42.7 - 2802 and 42.9 - 2808 average)

I decided to go right in the middle at 42.8 and check seating depth.

My 4th test was four 5 shot groups all at 42.8 working from 2.7950 to 2.7975 to 2.8000 to 2.8025. My average fps was 2827 and nothing grouped better than about 3 moa, now I am no great shooter but not that bad. The one silver lining was that the 2.800 group had an ES of 9 and that particular group had 2 bullets touching in one spot and 3 bullets touching 3 inches to the right. So I am going to stick with 2.8 for now and try another ladder from about 42.4 to 43gr and see if getting that speed back to 2810ish will help.

Who knows maybe it was just me...

 

[ken4570tc in WY]

You may want to try testing seating depths further away from the lands. I can't remember the thread but someone had a link to a bullet manufacturers recommendation to try seating depths as far back as .150 off the lands. There test data had shown there is usually a wide sweet spot (.020-.040) that will have good groups with low sd's. It's kind of doing a ladder test for seating depth. The big benefit would be not having to constantly be chasing the lands. I haven't got my .243 Win RPR load development far enough to check it out but I'm getting close.

 

[spife7980]

You may want to try testing seating depths further away from the lands. I can't remember the thread but someone had a link to a bullet manufacturers recommendation to try seating depths as far back as .150 off the lands.

http://www.bergerbullets.com/getting-the-best-precision-and-accuracy-from-vld-bullets-in-your-rifle/

 

[ken4570tc in WY]

Spife7980,

Thanks for providing the link! You may have hit the nail on the head for the OP. Some full length dies may be over working his brass or they may need to put a little lube inside the neck as well.

 

[Ricker]

That was when they went to crap was during seating depth testing. I am using 42.8gr of H4350.

My first test was a 1 shot ladder in .5 increments. (42.5 - 2790 and 43 - 2806)
My second test was a 3 shot more concentrated ladder in .3 increments (42.6 - 2809 and 42.9 - 2814 average)
My third test was a 5 shot in .2 (42.7 - 2802 and 42.9 - 2808 average)

I decided to go right in the middle at 42.8 and check seating depth.

My 4th test was four 5 shot groups all at 42.8 working from 2.7950 to 2.7975 to 2.8000 to 2.8025. My average fps was 2827 and nothing grouped better than about 3 moa, now I am no great shooter but not that bad. The one silver lining was that the 2.800 group had an ES of 9 and that particular group had 2 bullets touching in one spot and 3 bullets touching 3 inches to the right. So I am going to stick with 2.8 for now and try another ladder from about 42.4 to 43gr and see if getting that speed back to 2810ish will help.

Who knows maybe it was just me...

This is almost identical to my 140 gr load testing last weekend. I had good initial results working up to 42.6 gr and 42.9 gr so I settled on 42.7 (expected 2850-2860 fps) for seating dept testing. All my five shot groups were terrible at nearly 2 MOA. I needed to work in a new powder jug and different primers so I decided to start over.

On the second workup I had a low node ~2795 fps and a high node ~2850 fps. I did some quick seating dept testing at -10 increments off the lands to -30 in the low node and -10 to -50 on the high node ( I wanted the high node speed). All of the low node groups were good in the 1/2 to 3/4 MOA range but only the -10 depth was good on the high node with the -20 to -50 seating depths being just as bad as before.

What I learned last weekend was in my gun the 140 hybrids are more sensitive to seating depth the faster I push them. My next verification will be to test both nodes at -5 increments from touching the lands to -15 or -20 and verify good or bad.

6.5 Creedmoor
Broughton 26"
H4350
CCI 200 and Fed GM210M

If I could find 130 gr Hunting VLDs I would shoot them but everyone already knows the Berger availability thing. I've had them on back order for a few months.

 

[Deleted member 10043]

Sounds more like a mechanical problem. If Berger VLD is that sensitive than they can fuck off.

 

[supercorndogs]

Or you can just keep shooting. Speed, spead, speed. So-called nodes are generally too slow or unshootable high. The former puts you in an unnecessary wind handicap. I see too many people wasting time opting for a one caliber difference in non-statistical group size difference that even if true has no bearing down range and shooting too slow putting themselves at a disadvantage. A node is psychological. It's between your ears and has little to do with ammo complementing the rifle in addition to the shooter who is nothing more than a node killer even if it does exist. In my opinion node work up is still in the hypothesis stage with a long way to go before it can be called a theory.

Someone told me the other day that ironic was the most misused word in the english language. I told them it was more likely theory. I think node may be the most misused word in the reloading section. It has become so ambiguous I am not even sure what its supposed to mean anymore. It is pretty interesting to think about all the different methods used. A lot of what we do is very subjective due to interpretation of results. We are all just dirty hypothosizers.

 

[Milo 2.5]

Someone told me the other day that ironic was the most misused word in the english language. I told them it was more likely theory. I think node may be the most misused word in the reloading section. It has become so ambiguous I am not even sure what its supposed to mean anymore. It is pretty interesting to think about all the different methods used. A lot of what we do is very subjective due to interpretation of results. We are all just dirty hypothosizers.

Lol, I've hated the term node since the day I was exposed to it. But I've said since the day I bought my first chronogragh, that ES & SD numbers shrink along with group size.
I have my own technique for developing loads, utilizing QL, OCW, ladder tests, and a chrono, etc... I even tried with QL to use the OBT thing, I believe it has some merit, but I always come back to how can a 26" 30 cal barrel remotely mimic a 26" 6 mm barrel. Not complicating the shit out of things works best today.

 

[Deleted member 10043]

That was what I was trying to say, corndog. Much better job there.

 

[Brandon05_88]

Barrels speed up, especially cut rifled barrels.

I would just confirm my load using -0.4 gr, -0.2 gr, your load, +0.2 gr, +0.4 grain.
I call this a window, and not a node.
Find the edges of the window (powder charge), and load for the center.

 

[redneckbmxer24]

Nodes aren't BS, they're very real. When you have a flat or flatter spot when doing a ladder test, guess what that is? Look at 6.5 Creed with H4350 and 140's for example, 42.0-42.5gr is usually a big fat node in just about every rifle.

As to the original question, when the barrel speeds up I always do a small test to make sure that my node wasn't just a velocity node and it didn't fall out of it or is on the edge. I'll load 3 rounds each .1gr and .2gr lower and higher and shoot them over the chrono to verify. Whether it stays or moves slightly tends to be about 50/50.

A good barrel can easily take 100 rounds to flatten out from the time it starts speeding up so just make sure you account for that as well if it's not done yet

 

[Greg Langelius *]

If VLD's are sensitive, they are only part of the equation. The sensitivity could tend to be linked with leade angle.

Greg

 

[Deleted member 10043]

What is a "leade angle"?

 

[Milo 2.5]

What is a "leade angle"?

http://cdn0.grizzly.com/specsheets/t23209_as.pdf

Click, look at top right number, 1 deg 30, most reamers use this, but there are others.
There was a post last week about throat erosion, if you think how little of material is in that area, understand wear easier.

 

[Deleted member 10043]

Redneck, it is the word, "node" that is BS. It is a stupid misuse of the noun. People are using it improperly. It is a group of lines that intersect then branch out. That is not what is happening when you settle on a perfect load. It's an overly complicated means of already knowing there is a finite median when working up a load. Somebody has already done the work for us. Example, look up factory loads for 6mm Remington with 100 grain bullets. What is the predominant MV they are rated at? Why is that?

 

[Milo 2.5]

Redneck, it is the word, "node" that is BS. It is a stupid misuse of the noun. People are using it improperly. It is a group of lines that intersect then branch out. That is not what is happening when you settle on a perfect load. It's an overly complicated means of already knowing there is a finite median when working up a load. Somebody has already done the work for us. Example, look up factory loads for 6mm Remington with 100 grain bullets. What is the predominant MV they are rated at? Why is that?

At some point terms become irrelevant as long as the goal is reached. One more reason I do not like "node" is in your last sentence, MV tested, what if I shoot a 26" barrel and everyone else shoots 24", it's out the door.
It would simplify the heck out of things if we all had a universal means of measuring pressures, but even then, all barrels differ slightly.
EDIT: I hang on accurate shooter, there guys speak of a zone for 6XC, 3000fps is golden, Christ, they shoot 30" barrels, back track that shit.

 

[Deleted member 10043]

Well, now you're getting into pseudo, dangle, and regular node territory. Zone is the more appropriate terminology. Harmonics is another crazy term we misuse. A harmonic needs to be a frequency as a whole number in multiple of a reference wave. It is measured in hertz. Lately, I've been seeing reference to the entire rifle system as a tuning fork. Yet another reference to sound, in this case a standard pitch rather than mechanisms related to combustion and subsequent ballistics. We're using terminology that is measurable in other areas of physics with no means of measuring in our own area of physics.

 

[Milo 2.5]

Well, now you're getting into pseudo, dangle, and regular node territory. Zone is the more appropriate terminology. Harmonics is another crazy term we misuse. A harmonic needs to be a frequency as a whole number in multiple of a reference wave. It is measured in hertz. Lately, I've been seeing reference to the entire rifle system as a tuning fork. Yet another reference to sound, in this case a standard pitch rather than mechanisms related to combustion and subsequent ballistics. We're using terminology that is measurable in other areas of physics with no means of measuring in our own area of physics.

Lol. I personally refer to them as pressure ranges, it has never caught on with others. I do not speak in terms of barrel harmonics, but they are real, slo mo cameras prove that. So do barrel tuners. It's also as simple as changing charge weight and watching POI change.
The term aerodynamic jump irritates me, what became of spin drift in wind?

 

[Deleted member 10043]

If we could measure the harmonics of a barrel under combustion pressures we could simply back into load development mathematically. The bullet is being catapulted or pushed from 0 fps to x fps through the bore. At some point before exiting the bullet reaches the speed of sound and beyond. It hard to imagine any sort of harmony occurring during this transition. A muzzle brake was invented to reduce recoil for many reasons but I rarely see any discussion that it is being discussed as a means to reduce an equal and opposite effect related to barrel harmonics. Yes, a brake reduces recoil but does it increase accuracy without regard to felt recoil? Thus, proponents of barrel tuners on large barrels may be on to something except these devices work best on lighter barrels than what we use. Seriously, knowing where in the barrel the bullet is transitioning from trans to super sonic may be key to reducing vibrations and those silly inexpensive rubber barrel stabilizers may not be silly after all, lol. There will come a day when a certain cartridge load will be used to develop a custom barrel. Today, we inefficiently order and install a groovy barrel and then proceed with shooting in the dark developing a custom load for the barrel. Wouldn't it also be nice if the barrel came to the end user with the most efficient m/s range stamped on it to aid in load development. It would certainly separate those that are good load developers from those that have the better shooting fundamentals. It would also go a long way in ruining what we enjoy today, which is frustration to satisfaction. Maybe some things are best left alone. A node is a node and barrel harmonics is an accepted term within our community for we range from incredibly naive to overly intelligent and the passive to pompous egos that go with that. I would hate to see us like those rice burners that can only install a larger muffler.