.02 or .03 weight change ?

[bob4]

Loading for a 270 Winchester. Berger 130 VLD. Have been pretty happy at 58.5 of H4831. Sometimes 59 gns will out it. So I was wondering whether it was worth it to try .02 change or should I just go. 03 each direction? IE: After this I might try a slight seating change. So the same sort of question is posed there. Is .005 worth a try each direction from where I am or should I just try .010 ?

 

[g0rd0]

first define happy. If you are getting 2" or less groups at 200 yards you have the load. Instead of fudging with the charge try changing the seat depth +/- thou

 

[WeiserBucks]

I want to know what scale your using to measure .02 , or twenty thousandths of a grain of powder accurately. I'm also curious if H4831 weighs less than .01 grains per kernel to make any adjustments valid.

 

[Lonewolf74]

I second changing seating depth first. I would go .006 in both directions in .003 increments, that is if you have your seating depth close to begin with. Then play with the charge some again if you want and I would do .2 grain increments.

 

[tbrice23]

I'd go .5 grain. Thats only 20 fps at most.

Just for context tomorrow I'm working up H50bmg in 26 Nosler in one full grain increments. Which will be 20 to 25 fps.

 

[cdherman]

I'd go .5 grain. Thats only 20 fps at most.

Just for context tomorrow I'm working up H50bmg in 26 Nosler in one full grain increments. Which will be 20 to 25 fps.

Its not the fps that matter but the node. In the node, the accuracy, fps, point of impact are supposed to be sort of "suspended". I dunno. That's what I read. That's what I have experienced too. But I would disagree that .2 grain is too small. 0.5 grain is fine to get some general ideas. Final development should be with intervals of 0.5% or less. In a cartridge with 60gr, that would be 0.3 grains, OR LESS.

Lots of voodoo about nodes out there. If you find an accuracy node that is so small that you miss it with a 0.5 grain series, then the problem is that that node is small enough that all sort of other factors can move it around. Like temp, altitude, pressure, your throat burning out gradually, your brass getting hard, (or soft after annealing).... A good node and good gun (with a good cartridge choice) is going to be broad.

So you find a node with broad strokes (while you are also making sure that the top loads are not too hot for your gun) and then you drill down with some smaller increments.

The 270 win, being a long cartridge with a long powder column, is supposed to be inherently less accurate and more finicky about loads. BUT, IMO, its also as near to "balanced" as it comes in terms of capacity to bore. Its not overbore, not anymore with modern powders at least. So that makes it easier to load for.

Enjoy.....

 

[sendero7]

Its not the fps that matter but the node. In the node, the accuracy, fps, point of impact are supposed to be sort of "suspended". I dunno. That's what I read. That's what I have experienced too. But I would disagree that .2 grain is too small. 0.5 grain is fine to get some general ideas. Final development should be with intervals of 0.5% or less. In a cartridge with 60gr, that would be 0.3 grains, OR LESS.

Lots of voodoo about nodes out there. If you find an accuracy node that is so small that you miss it with a 0.5 grain series, then the problem is that that node is small enough that all sort of other factors can move it around. Like temp, altitude, pressure, your throat burning out gradually, your brass getting hard, (or soft after annealing).... A good node and good gun (with a good cartridge choice) is going to be broad.

So you find a node with broad strokes (while you are also making sure that the top loads are not too hot for your gun) and then you drill down with some smaller increments.

The 270 win, being a long cartridge with a long powder column, is supposed to be inherently less accurate and more finicky about loads. BUT, IMO, its also as near to "balanced" as it comes in terms of capacity to bore. Its not overbore, not anymore with modern powders at least. So that makes it easier to load for.

Enjoy.....

 

[sendero7]

Once I feel I have the load down pat, I'll try .1 on each side to verify. That .1 of a grain can tighten up a group dramatically.

 

[tbrice23]

Its not the fps that matter but the node. In the node, the accuracy, fps, point of impact are supposed to be sort of "suspended". I dunno. That's what I read. That's what I have experienced too. But I would disagree that .2 grain is too small. 0.5 grain is fine to get some general ideas. Final development should be with intervals of 0.5% or less. In a cartridge with 60gr, that would be 0.3 grains, OR LESS.

Lots of voodoo about nodes out there. If you find an accuracy node that is so small that you miss it with a 0.5 grain series, then the problem is that that node is small enough that all sort of other factors can move it around. Like temp, altitude, pressure, your throat burning out gradually, your brass getting hard, (or soft after annealing).... A good node and good gun (with a good cartridge choice) is going to be broad.

So you find a node with broad strokes (while you are also making sure that the top loads are not too hot for your gun) and then you drill down with some smaller increments.

The 270 win, being a long cartridge with a long powder column, is supposed to be inherently less accurate and more finicky about loads. BUT, IMO, its also as near to "balanced" as it comes in terms of capacity to bore. Its not overbore, not anymore with modern powders at least. So that makes it easier to load for.

Enjoy.....

I've referred to it as barrel time in relation to harmonics. A lot of times I can feel the "dampened feel" of a tuned load opposed to a "twang" feel of an un-tuned load. Hard to explain but there is definitely a different feel .

I guess my point is if l ever have a cartridge that is dependent on .01 gr I'm finding another cartridge to shoot.

 

[cdherman]

I guess my point is if l ever have a cartridge that is dependent on .01 gr I'm finding another cartridge to shoot.

Exactly. Because that means there are so many variables that can throw it off, that the group size will never be consistent. Even if you diligently weight every charge on a beam scale, prep every case the same. Variables you cannot control will ruin your day.
Cold barrel, dirty barrel, clean barrel, different powder lot, different primer lot, etc etc.

 

[bob4]

Thanks all. Sorry about my .02 ( 100THS) as should have read .2- .3 grains of powder. In any case, Went from CCI LRP to Fed 210.( finally got my hands on some) Ended up with .5 less in powder charge to get an accuracy node. This was a month ago. I'm not changing any 2 things at once. Got me wondering if I changed something else slightly if things could improve on average. But maybe lose the occasional 1/2-3/4 inch flyer. ( Probably not) I don't expect my factory rifle to shoot clovers constantly. Decided at this point to try .3 gns difference to see what happens. Then I will try seating changes by .005 just to see. I continue to learn a bit this way and have fun doing it in the process.

 

[DUSTY NOGGIN]

i personally think 0.1 grain is worth measuring to even on 100 grain case, but only after ive narrowed down everything else

the speeds of each shot also determine the timing of the bullet when last touching the barrel , i bet your flyers are all caused by either a faster or slower velocity bullet , and since your factory 270 is a thinner barrel its moving more and changing temp faster than a heavier contour barrel would -

maybe if you tried a lighter bullet pushed at higher velocity might help with timing leaving the muzzle , but that is starting all over

 

[Remmy700]

I want to know what scale your using to measure .02 , or twenty thousandths of a grain of powder accurately. I'm also curious if H4831 weighs less than .01 grains per kernel to make any adjustments valid.

There are several scales that get that low I have an A&D FX120i it does .02 there are higher end scales that go one more decimal spot. Most powders I have used weigh around .02 to .04. Concerning question to OP what is ES with current load? If I cant get my ES below 8 or so I don't care how it shoots I am moving on with another combo. Once I get a nice low ES/SD and somewhat good grouping I then will start tweaking seating depth. I typically do load test in a .2 gr charge increments once I get two to three increments on a row where the fps flatten out I then explore that area farther going in .1 increments. In my experience and I know there are exceptions but when I have low single digit SD/ES those groups are normally fairly good and have always been able to close them completely up with seating depth after that.

 

[Remmy700]

I started doing the 10 round load test method and so far it has confirmed the low ES/SD numbers showing nodes, dont even need a target. Not right or wrong just the way I prefer to do it now.