What difference does .1 or .2-.3 gr make?

Sea Buck · August 16, 2011, 08:05 PM

I'm reloading on my 5-0-5 RCBS scale and it alomst never weighs the same charge twice, which is the by product of my Lyman "cruncher" measuer which never throws the same charge twice.But,depending on the powder I do get a .1 to a .5 gr difference.I draw the line at .2-.3 grains. I'm not a bulls eye shooter...what difference does a . 1 to a .5 gr spread make? If I shoot at anything in this neck of the woods it will be less than 100 yds.

olddav · August 16, 2011, 08:21 PM

What are you loading, I assume you are using them for hunting?

jdscholer · August 16, 2011, 08:49 PM

A .5 gr. spread usually indicates very long grain powder, a really crappy measure, inaccurate scale, poor powder measure technique. Maybe even the involvement of a ceiling fan.

Seriously, a combination of a few of the above reasons is usually needed to have an error of .5 gr. If ya can't do a little improvement on these factors you're just gonna have to throw light charges, and trickle them up to spec.
What kind of powder, and how large of charges are we talking? jd

buck460XVR · August 16, 2011, 09:20 PM

A lot depends on the powder and the size of the charge. .5gr in a 4.0gr charge can make a big difference. .2gr in a 45gr charge would be almost impossible to notice.

Quote:

I'm reloading on my 5-0-5 RCBS scale and it alomst never weighs the same charge twice, which is the by product of my Lyman "cruncher" measuer which never throws the same charge twic

I'm confused...is it the scale or the powder measure or both? if it's the scale(and it's a good one) check it against checkweights and clean the knives. If you still are having problems, call RCBS, they'll take care of it. If it's the measure, maybe you need a baffle. Could be static, wipe the inside down with a used dryer sheet. Some powders just don't measure well. Some bulky powders like Unique will vary by weight even when volume is the same. In most cases, a .2 gr variance in Unique(+/- 1 gr) to me is acceptable.

Edward429451 · August 16, 2011, 09:48 PM

.5 could make all the difference in the world depending on what you're loading and what powder. Some powders meter better than other powders. A simple thing that I do to help ensure consistency and safety in measuring powders is to weigh 10 sample charges when I open the can for the first time, and record the weights and target weight. Plug it into the Chrony formulas and I have the average deviation from average weight and the extreme spread of weight variation.

I tape this to the can of powder and then when I am using that powder I know what to expect in variations. Obviously, the closer to max the more attention is paid to it.

FrankenMauser · August 17, 2011, 02:26 AM

With most powders in .25 Auto or .32 Auto, 0.1 grains can be the difference between a safe load, and a blown primer. An extra 0.3 grains can result in a ruptured case. With some powders in .380 Auto, 0.1-0.2 gr can be the difference between a safe load, and a blown primer. An extra 0.3-0.5 grains can make for a very bad day.

In most other cases... It's just a matter of accuracy.

wncchester · August 17, 2011, 07:33 AM

All measures are volume devices; there is no way to make such a measure totally consistant in function but they all do pretty good with fine grained powder while none of them are great with coarse, large grained powders. I've used them all and know of no brand that makes a poor measure but I do know some poorly functioning users that make things worse.

For rifle shooting inside 100 yards I doubt anyone would ever see any difference with +/- .5 grain in a midsize or bigger cartridge. Small cartridges generally use fine grained powders and even with poor operating technique I can't see a hazardous amount of variation with that.

old roper · August 17, 2011, 07:53 AM

Sea Buck, Depending on powders it pretty hard to get some to meter thru a powder measurer that will weight what you want.

I understand what you allow myself if I'm going to reload and I get a load that shoot good say at 45gr that's what I'm going to load. I don't mind using a powder trickler it's right next to my scale.

I have a BR powder measurer that I use at the range on some calibers. In small cases like the 222 etc .1 to .5 gr difference is a big deal. I'm not much into pistol/shotgun loading so cann't comment on those.

Calibers like my 280AI I test my load like this 56.5gr,57gr,57.5 on up and I do that with all my deer/elk rifles. I can tell a difference and I see it in the chrongraph also but I'm not shooting factory rifle.

Uncle Buck · August 17, 2011, 08:50 AM

Like Buck460 and FrankenMauser says, depends on the round. When using the powder in a rifle cartridge, not to much worry about accident.

The smaller case cartridges, .1 ~ .5 grains could be the differences between "that was fun" and "That was really stupid and PAINFUL"

If your powder measure will not hold the correct setting, I would look for another. You could get in the habit of throwing under the desired weight and then use a trickle to bring it to the correct weight.

I use a homemade copper spoon when I need to trickle the load to exact weight.

Sea Buck · August 17, 2011, 12:15 PM

Thanks for all the response. My Lyman powder measure likes to be at least 3/4 full to throw an accurate charge(+ - .2) of flake powder.Occasional.3-.5 if I am not paying attention to my powder level.I am very careful of my loads with Bullseye,and Unique for my .38/.357 and .45ACP, and keep them on the plus side.I actually like Bluedot and have used it for years,when I can get it.It is very forgiving and you cannot double charge.I eyeball all my charges anyway.Dumb not to. I am now using Herco, as I cannot find Bluedot. I have given up on extruded powders.They just do not meter,and I dislike having to crunch through the grain to meter the charge.I do not mind using the powder trickler to get an exact charge when loading for rifle rounds: .30-03,.243, .30-40,.30-30,.223.and I like H414and H380.

Civil War Life · August 17, 2011, 02:05 PM

Quote:

If ya can't do a little improvement on these factors you're just gonna have to throw light charges, and trickle them up to spec.

That is what I do. Works for me. I use a digital scale that I check with a bean scale every 10 rounds.

Gunplummer · August 17, 2011, 04:24 PM

The Frankford Arsenal did a study on high-powered rifle rounds and found that the being off a few grains did not really have much of an affect on accuracy. The biggest change was from different lots of primers and different brands of primers. This is in the original NRA Handloaders Guide. This study was only done with high-powered military rounds.

August 16, 2011, 08:05 PM	#1
Sea Buck Senior Member Join Date: September 9, 2008 Location: New England,Florida Snow Bird Posts: 312	What difference does .1 or .2-.3 gr make? I'm reloading on my 5-0-5 RCBS scale and it alomst never weighs the same charge twice, which is the by product of my Lyman "cruncher" measuer which never throws the same charge twice.But,depending on the powder I do get a .1 to a .5 gr difference.I draw the line at .2-.3 grains. I'm not a bulls eye shooter...what difference does a . 1 to a .5 gr spread make? If I shoot at anything in this neck of the woods it will be less than 100 yds.

August 16, 2011, 08:21 PM	#2
olddav Senior Member Join Date: December 21, 2008 Location: Lower Alabama Posts: 727	What are you loading, I assume you are using them for hunting? __________________ Never beat your head against the wall with out a helmet

August 16, 2011, 08:49 PM	#3
jdscholer Senior Member Join Date: March 23, 2008 Location: Jefferson State Posts: 1,197	A .5 gr. spread usually indicates very long grain powder, a really crappy measure, inaccurate scale, poor powder measure technique. Maybe even the involvement of a ceiling fan. Seriously, a combination of a few of the above reasons is usually needed to have an error of .5 gr. If ya can't do a little improvement on these factors you're just gonna have to throw light charges, and trickle them up to spec. What kind of powder, and how large of charges are we talking? jd __________________ "We're all dummies, just in different ways." Old Okie Philosopher

August 17, 2011, 02:26 AM	#6
FrankenMauser Senior Member Join Date: August 25, 2008 Location: In the valley above the plain Posts: 13,424	With most powders in .25 Auto or .32 Auto, 0.1 grains can be the difference between a safe load, and a blown primer. An extra 0.3 grains can result in a ruptured case. With some powders in .380 Auto, 0.1-0.2 gr can be the difference between a safe load, and a blown primer. An extra 0.3-0.5 grains can make for a very bad day. In most other cases... It's just a matter of accuracy. __________________ Don't even try it. It's even worse than the internet would lead you to believe.

August 17, 2011, 08:50 AM	#9
Uncle Buck Senior Member Join Date: June 21, 2009 Location: West Central Missouri Posts: 2,592	Like Buck460 and FrankenMauser says, depends on the round. When using the powder in a rifle cartridge, not to much worry about accident. The smaller case cartridges, .1 ~ .5 grains could be the differences between "that was fun" and "That was really stupid and PAINFUL" If your powder measure will not hold the correct setting, I would look for another. You could get in the habit of throwing under the desired weight and then use a trickle to bring it to the correct weight. I use a homemade copper spoon when I need to trickle the load to exact weight. __________________ Inside Every Bright Idea Is The 50% Probability Of A Disaster Waiting To Happen.

August 16, 2011, 09:48 PM	#5
Edward429451 Junior member Join Date: November 12, 2000 Location: Colorado Springs, Colorado Posts: 9,494	.5 could make all the difference in the world depending on what you're loading and what powder. Some powders meter better than other powders. A simple thing that I do to help ensure consistency and safety in measuring powders is to weigh 10 sample charges when I open the can for the first time, and record the weights and target weight. Plug it into the Chrony formulas and I have the average deviation from average weight and the extreme spread of weight variation. I tape this to the can of powder and then when I am using that powder I know what to expect in variations. Obviously, the closer to max the more attention is paid to it.

August 17, 2011, 07:33 AM	#7
wncchester Senior Member Join Date: December 1, 2002 Posts: 2,832	All measures are volume devices; there is no way to make such a measure totally consistant in function but they all do pretty good with fine grained powder while none of them are great with coarse, large grained powders. I've used them all and know of no brand that makes a poor measure but I do know some poorly functioning users that make things worse. For rifle shooting inside 100 yards I doubt anyone would ever see any difference with +/- .5 grain in a midsize or bigger cartridge. Small cartridges generally use fine grained powders and even with poor operating technique I can't see a hazardous amount of variation with that.

August 17, 2011, 07:53 AM	#8
old roper Senior Member Join Date: June 11, 2007 Posts: 2,155	Sea Buck, Depending on powders it pretty hard to get some to meter thru a powder measurer that will weight what you want. I understand what you allow myself if I'm going to reload and I get a load that shoot good say at 45gr that's what I'm going to load. I don't mind using a powder trickler it's right next to my scale. I have a BR powder measurer that I use at the range on some calibers. In small cases like the 222 etc .1 to .5 gr difference is a big deal. I'm not much into pistol/shotgun loading so cann't comment on those. Calibers like my 280AI I test my load like this 56.5gr,57gr,57.5 on up and I do that with all my deer/elk rifles. I can tell a difference and I see it in the chrongraph also but I'm not shooting factory rifle.

August 17, 2011, 12:15 PM	#10
Sea Buck Senior Member Join Date: September 9, 2008 Location: New England,Florida Snow Bird Posts: 312	Thanks for all the response. My Lyman powder measure likes to be at least 3/4 full to throw an accurate charge(+ - .2) of flake powder.Occasional.3-.5 if I am not paying attention to my powder level.I am very careful of my loads with Bullseye,and Unique for my .38/.357 and .45ACP, and keep them on the plus side.I actually like Bluedot and have used it for years,when I can get it.It is very forgiving and you cannot double charge.I eyeball all my charges anyway.Dumb not to. I am now using Herco, as I cannot find Bluedot. I have given up on extruded powders.They just do not meter,and I dislike having to crunch through the grain to meter the charge.I do not mind using the powder trickler to get an exact charge when loading for rifle rounds: .30-03,.243, .30-40,.30-30,.223.and I like H414and H380.

August 17, 2011, 04:24 PM	#12
Gunplummer Senior Member Join Date: March 11, 2010 Location: South East Pa. Posts: 3,364	The Frankford Arsenal did a study on high-powered rifle rounds and found that the being off a few grains did not really have much of an affect on accuracy. The biggest change was from different lots of primers and different brands of primers. This is in the original NRA Handloaders Guide. This study was only done with high-powered military rounds.