been thinking about acuracy.

[Evan03]

is ingnorance bliss here?

been thinking somehow im easily getting my rifles to shoot were it kinda seems others are doing alot more to get theres to shoot.

im doing basic case prep im not turning or trueing to same length basicaly all i do is run em through the resizer scrub out the case necks and primer pockets wipe of the case lube and use a qtip iside the case kneck incase an oil was in there.

im finding the 2506 is the easiest to size. im not lubeing the inside of the case knecks also i found that putting case lube on the foam pad that comes in the nosler bullet boxes works best for lubeing my cases that rcbs oil pad deal was kinda a pain.

3006 cases seemed to be kinda finicky to resize i set up the dies per rcbs directions and procedded to dimble the shoulders. bumped the dies off a bit and all was good. though they arent completly full length sized now.

the 220 was finicky the same way, in its lenght after full lenght sizeing they needed trimmed to fit in the chamber right. also this is #1 action may be alittle difrent and tighter than my bolt actions

so basic sizeing and prepp then all loads are trickled to the same exact charge. wich is i think were my acrucy is comeing from. i got curious the other day and set the scale at 1 grain to see how much powder that was. i was suprised to find that there were about 20 granuals of rl19 sitn there when i was done. i wouldnt have figured that much.
wich means my loads are way tighter than a 1grain tolerance. each load is tricled out to dead nuts on.

i think since im new and just going with it that things are comeing fairly easy. it seems each time i do a new load or powder combo i find a load that meets my standerds in no more than 7 powder charges. this is after going to sujest most acurate powder in the nosler manual

i spent this morning dinkn around sizeing and prepn 2506 cases. ive about burned through 100 win mag primers in a week. all in the 2506. ive got 50 cases prepped and primed and am off to drop powder and bullets now.

gona do range test to 300yds and see how she does this after noon. hopn to have 50rds done by about 1 hopefully sooner than that.

later
Evan

[Rocky Raab]

Evan, trickling powder to "exact" weight can't hurt. But it doesn't help much, either.

Denton and I discussed this the other day while we were at the range. He's working on an article i which he's testing powder dispensers for accuracy, and I've had an article in mind about the need (or not) of precise charge measuring.

What we agreed on is that something like a 1% variation in powder charge weight is meaningless. With a 50-grain charge, that means a half-grain variation from charge to charge has NO appreciable (or statistically meaningful) effect on either velocity or pressure.

There are so many other things that have an effect that powder charge weight just gets buried in the sum of the other causes.

The bottom line is that any dispenser that keeps powder weights with a few tenths of a grain is perfectly fine.

Weighing down to "dead nuts on" is okay. It can't hurt. Don't stop if you want to do it.

But it doesn't help, either.

[Evan03]

well you guys may be right.

in all honesty i may not be shooting better than facotry

i may have just found the right bullet powder combo. just like you would if you were shooting facotry rds and testing difrent makes. only difrence is im just tesing my loads.

anywas its still all forieng to me.

id think a half grain varition would do something regardless of wether we think its much of anything. that like 10 granuales of powder. thats either been added or taken away from the charge.

just thjink if you layed 50gers of rl19 end to end and lit them. it would quit burning noticably sooner or last longer with those 10granules.

like i said its foreign to me.

if you were me would you change your reloading practices

Evan

[Rocky Raab]

As I said, if it makes you happy to trickle powder down to zero, go ahead. (That may sound a bit smart-aleck. It's not meant that way at all.)

But there are so many other differences from round to round that a variation in charge gets masked by the other differences. For example: brass isn't the same. It may be thicker on one side than the next case - and by different amounts than another one. Brass hardness varies. Primer pockets are different depths, diameters and/or roundness. Flashholes are different diameters and smoothness. Bullets are of differeing diameters and with different bearing lengths. Jackets may be of different alloys, thicknesses and temper. Same with their cores, plus add bubbles or incomplete core fills. Add different seating depths, bullet pull, crimp and even the changing amount of fouling with each shot to the list.

ALL of those things affect pressure and velocity. There are even more things in the gun that affect accuracy, and can change from shot to shot, too. Throw in the wind and weather while we're at it.

Heck, it's a wonder we get any two shots to land even close to each other, much less do it repeatedly!

Finally, let me throw in this zinger: just because the scale SAYS it's the same charge weight (zero), how do you know IT isn't a bit off either way?

[George Foster]

I know you say that a .5gr difference in powder charges doesn't matter but I have to disagree with you. My testing shows that a .5gr difference does make a big difference in group size at times. I have seen quite a few times when the .5gr change in the charge has made 1/2" or more in group size. It may not affect velocity and pressure that much but it must affect the barrel harmonics.

[Lone Star]

Long range and highpower shooters ( the top ones anyway) get sub-moa accuracy out to 1000 yards with charge variations of .2 to .3 grains in the .308. They often use IMR4064 and IMR4895, and although 4064 does not throw consistent charges many prefer it because accuracy is better even with the variation. This is hard for the average handloader to accept given all the BS published in the slicks, but it is proven every year in competition. Short range BR shooters prefer less variation, but do they really need to? Virtually none of them weigh their charges.....but they shoot bughole groups anyway.

One thing these guys do is shoot a lot. They shoot enough groups - and record their results - to get a real picture of what effects accuracy. The average shooter's "testing" consists of shooting a few groups at 100 yards with one load, averaging the group size, then moving on. Statistically this method is BS and proves very little, although we usually fool ourselves into thinking our load shoots better than it does.

Shooting at 100 yards is also a poor way to test loads that will be used at longer ranges. A load which shoots 1 moa at 100 yards may not do so at 500 yards. This may be due to the load, but more likely it is due to the environment. Wind, mirage, temperature, shooter skill - all play a major role in long range accuracy. Bottom line is that at longer ranges minor differences in charge weight is completely overshadowed by outside factors.

[Rocky Raab]

George, that half-grain is not a hard and fast number. If you read higher up, I specifically said that up to a 1% variation is essentially meaningless. I did give the example of a 50-grain charge in which a 15 Variation would amount to a half grain, but the real number to remember is the 1% one.

In the 308, with target loads, those guys are probably using charge weights in the 35-45 grain area. If they've found that .2 to .3 grains variation doesn't hurt their accuracy, that validates my point: those variations are just under 1%.

The comments about statistics are valid, too. A half-dozen three- or five-shot groups tells us nothing.

[Evan03]

what about a half dozen three or five shot groups with 7 difrent powder chargers, thats goat tell us something, lol


ill remeber the next time im shooting the broad side of barn that i realy shouldnt be able to because of all the variables. :)

[Freebore]

What i have found that once a load is developed at 100 yards to most deffinately move to 200 and 300 yards. This where I do my tuning. The last thing I do is change to differant primers.
I propably do things a little different than most as I look to drive a particular bullet in a given caliber at a specific velocity to attain the performance I demand from my cartridges w/sub MOA accuracy.
I think the variance of powder charges must be within acouple of kernnals at the upper level of velocities. Which I think where the harmonics are definately much more in play with lightwieght hunting barrels.
EVERY charge is weighted to the exact, overall lenght is exact, and runnout is within .0015.
I want every advatage in my favor for my shot. Pretty particular for factory chambers... the same set-up as my customs. A given rifle is only as accurate as the best ammo available.
Keep weighing every charge Evan.

[Ridge Runner]

if 1/2 gr. makes a difference than would it stand to reason that the only way to get the "exact" same results every shot with identical charge weights is for every granule of powder must be in the exact same location position in each case?
I agree in small capacity cases (IE 22 hornet, 221 fb) but in the bigger jugs does 10 granules of powder matter?
RR

[Rocky Raab]

( I should NEVER have used that half-grain as an example...)

Once again, my contention is that a ONE PERCENT variation in powder charge is insignificant.

[Catfish]

The general rule of thumb for figuring gains in velosity when makeing cases larger, Ackley improveing ect., is that you get an increase in velosity that is 1/2 the percentage increase in volume. This is not 100%, good enough to work with. Useing this formual a 1% increase should give you a 1/2% increase in velosity, or about 20 fps. with a round fireing at 4,000 fps. I take about 100 fps. to gain an extra 5 yrds. in point blanck range which mean that we are talking about less than 1 yrd. max. point blank range increase from a gun this is already point blank at abt. 400 yrds. Unless your gun is shooting sub 1/2 moa to start with you`ll never be able to find the vairation due to a 1% vairation in powder charge.
What Rocky said!!!!!!!!!!!!!!!

[Freebore]

catfish,
I won't keep a rifle that will NOT shoot 1/2 MOA at 100. Point being this is the reason for the prescion loading techniques. Precision not required I agree with, .. if your criteria of exceptance of accuracy consistancy is within a given range. My range is exactlly not more than 1/2 MOA.

[Catfish]

Freebore,
I have a friend that brought out an SKS he wanted to use for a deer rife. We got it to shoot gruops of abt. 3 1/2 moa. and he thought that was great. I, being more like you though he was crazy and pointed out to him that those were crappy groups. His reply was that, this is a deer rifle that will never shot at a deer more than 75 yrds. away and at that range that`s a heart shot every time.
To stay below 1/2 moa it is usually nessary to do alot more case prep than most shooters are willing to and most shooters can get by very well with guns that shoot 2 moa. BR competors of coarse need gun that shoot much better than 1/2 moa on a clam day or they can stay home. Serious pd shooters need at least 1/2 moa accuracy for long shots, but big game rifle need not shot that acurately as their targets are larger and closer.

[Paul5388]

I think part of the point being missed here is, dumped/thrown powder isn't any different than what factory loads use. I don't suppose most of us would consider using factory loads for serious shooting or we wouldn't be hanging around a reloading website.

How do we know the powder scale is right? We check with calibration weights and we don't use electronic scales. I use a set of M2 calibration weights (and I don't handle them with my fingers!) for my scales, but obviously they are never going to have the accuracy of an analytical balance. Even so, I expect my Ohaus 505s to give me accurate weights to <.1 gr, when they have been zeroed properly. With rounding off, that degree of accuracy isn't possible with electronic scales normally encountered in reloading.

[Evan03]

thank you guys for your great words of wisdom. im very new to this game and wanted to see what you all had to say on the subject.

i only can hope to gain half the knowledge that you have.

thanks

Evan