School of Thought on Velocity Nodes. Fast or Slow?

[MDof2]

What's the school of thought on picking a velocity node when doing a load workup and finding multiple nodes? OCW method or others;

I'm tinkering around with Following Scott Satterlee's method of 10 shots (or more for example, say 20 shots) and say for example you find nodes (plateaus) at lower velocities, as well, in the higher range of speed / near max published charge?

Pick the higher nodes? Any specific reason why? Other than full cases being preferred by conventional wisdom?

Appreciate any insight on the topic.
I see people doing load development and picking different loads to hone in on, and I'm at now at that same point. Ran everything across the crono and have tinkered with some 5 shot groups of each, all showing respectable results.

 

[Archie]

For a target intended load, the lower velocity nodes will generate less recoil giving a multitude of benefits to the shooter. (Cases and shoulders last longer.) Of course, for long range targets, one needs to allow for long range drop and ease of adjusting sights.

For hunting, one wants suitable power. However, the range must be considered as well as the size of game. One might want a bit more velocity and power for some applications, but above a certain level, velocity increase really means little. Reliability means a great deal.

 

[tightgroup tiger]

I chase the accuracy nodes, not the velocity nodes. If I can find an accuracy node in a recoil range that I can deal with, then that's where I'm heading. It may not be full throttle but at least I will have more confidence in my loads which puts me at ease a little more to hit my POA.

 

[Chuck R.]

The way I read and have applied the OCW method leads me to the higher velocity nodes just based on the instructions and using "max charges" as the starting point. I simply developed a spreadsheet that does the calculations based of the 3 max charges entered. As the above poster stated, I chase the accuracy node.

3. Consult at least three load data sources for maximum charge weight for the powder you've selected. Powder manufacturers are the most reliable source. You must then decide on what your maximum charge will be. I just use the 3 max charges as my starting point.

4. Back away from the maximum charge by 7 to 10 percent, and load one test round with this charge. Add 2% to the charge weight, and load another cartridge with that charge. Load a third test cartridge with the next 2% graduation. You will use these three cartridges for sighters, and more importantly to determine pressure tolerance in your individual rifle.

5. Add another 2% or so to the charge level used in cartridge #3 of step 4, and load three rounds with this charge weight. Add .7% to 1% to this charge, and load three more. Add that same graduation again, and load three more. Continue adding the chosen graduation until you have moved ONE increment above your chosen maximum powder charge.

http://optimalchargeweight.embarqspace.com/ocw-instructions/4529817134

 

[MDof2]

For a target intended load, the lower velocity nodes will generate less recoil giving a multitude of benefits to the shooter. (Cases and shoulders last longer.) Of course, for long range targets, one needs to allow for long range drop and ease of adjusting sights..

These would be for target loads.

The way I read and have applied the OCW method leads

Satterlee's method skins the cat a little different in that you establish velocity, then hone in on accuracy.

Vaughn puts it to the coals.


Scott explains it here:


Some love it, some hate it. I'm not married to it, but having fun and learning a bit playing with it.

Here are the two loads that bring the question up. Notwithstanding what may be shooter error on one of the shots taking the higher charge from .3moa to .7, or simply looking at verticle stringing alone, my question on faster vs slower started wandering around in the back of my mind to conventional thinking.....



versus

 

[Bfh_auto]

If I don't get acceptable accuracy at the high node. I moved to another powder.
In things like my Krag. I use the lowest accurate load.

 

[Steve S.]

The lower node suits my needs for exceptional accuracy and adequate horsepower for my hunting distances - shot placement is key, a couple hundred fps is not - the tad lower recoil probably helps also but I can say that the difference is not noticeable to me. If I were a long range shooter, then maybe my needs would shift to a higher pressure node.

 

[AJC1]

Competition means highest node all other considerations come second.
Noncompetion- pick the widest node for best accuracy in changing conditions. Choose a lower node to increase brass life and reduce barrel heat and throat erosion.

 

[rbernie]

Pick the higher nodes? Any specific reason why? Other than full cases being preferred by conventional wisdom?

I pick powders, not charge weights, to give me a full case. I also try to keep my loads off of max, because (even when using powders that are relatively temperature insensitive) hot conditions have made things sticky for me the past (literally, as well as metaphorically in terms of shot variability) and I'd just as soon avoid that.

 

[MDof2]

Competition means highest node all other considerations come second.
Noncompetion- pick the widest node for best accuracy in changing conditions. Choose a lower node to increase brass life and reduce barrel heat and throat erosion.

Velocity being paramount to accuracy at distance.

 

[Archie]

These would be for target loads.

Yup.

Here are the two loads that bring the question up.

- a .25 inch group and a .67 inch group -

What caliber is this and what is the purpose? Both are accurate enough for North American game. (The rifle may not be suitable for Kodiak bear...) Depending on caliber and recoil, the tighter group at lesser velocity will generate less recoil, which will ease one's chiropractor bills. The larger group (again depending on the caliber, etc) would serve for larger game - Kodiak bear - and the extra velocity might be appreciated.

For target or varmint loads? The tighter group. Just one old man's thoughts.

 

[MDof2]

For target or varmint loads? The tighter group. Just one old man's thoughts.

Target. PRS shooting / "go to" load. Mid-range to longer range 1000ish yards.

 

[Stevenvalleyky]

My load testing is generally geared towards hunting rounds and mostly I have almost always leaned towards the higher velocity accuracy node even if I went slightly over max book loads provided I didnt observe any signs of overpressure simply for the wider margin of error if that buck of a lifetime steps out at 300 yards. However, recently been hunting a place where almost all my shots at deer will be 30- 120 yards. At 30 yards, a 150 gr SST will explode on even the softest parts of a whitetail with little penetration. I love the bullet in my 308 so rather than find a tougher bullet for shot under 50 yards, I simply load to the lower accuracy node so the bullets impact at 2400 instead of 2950 fps. Dont really have much difference at 100 yards and I would definitely want the upper charged loads if I'm expecting a longer shot. So I choose based on intended range of target for me.

 

[Demi-human]

Consistent Velocity being paramount to absolute accuracy at distance.

At longer ranges the faster load has less wind influence, compensating for an ever so slightly less accurate delivery.

In an already accurate rifle, and knowing shooter, for example, not me.

 

[Allen One1]

In PRS style shooting I think you are going to want the higher velocity load. I would load 10 more rounds and see if it holds up, maybe test some seating depths and see if it tightens up. Then take it out to 600 and see if it is staying together.

 

[MDof2]

In PRS style shooting I think you are going to want the higher velocity load. I would load 10 more rounds and see if it holds up, maybe test some seating depths and see if it tightens up. Then take it out to 600 and see if it is staying together.

Yep, did just that and found another couple options in the 2750 fps neighborhood.

 

[MDof2]

Two potentials. Kinda wish I had loaded a couple to get data just above 41.5 as I didn't see anything with regards to pressure signs.
I'd be happy with the mid 2700's fps if that shoots / groups well with respectable SD/ES numbers.

 

[Varminterror]

In PRS style shooting I think you are going to want the higher velocity load.

Competition means highest node all other considerations come second.

Not for most PRS/NRL competitors I know.

Running a high node load typically means sticky bolt or potentially stuck cases on the clock if weather gets wet or temps get high. Not worth it for 30-50fps. For some rounds, high node would even mean breaking the speed limit.

It’s really not so complicated - it’s not usually a choice between an “accuracy node” and a “velocity node”. At long range, they go hand in hand, and at short range, they often align, in my experience.

 

[AJC1]

Not for most PRS/NRL competitors I know.

Running a high node load typically means sticky bolt or potentially stuck cases on the clock if weather gets wet or temps get high. Not worth it for 30-50fps. For some rounds, high node would even mean breaking the speed limit.

It’s really not so complicated - it’s not usually a choice between an “accuracy node” and a “velocity node”. At long range, they go hand in hand, and at short range, they often align, in my experience.

PRS was not stated until after my statement. I shoot metallic siloette where we do. A full explanation in the beginning helps give better answers as they apply. I have zero prs experience.