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Phillip Allen
07-31-2009, 01:46 PM
I finally bought one and am dismayed to find it varies in readout by plus or minus as much as 0.2 grains...but more frequently by plus or minus 0.1 grains

it doesn't instill confidence when the max load is only 1.0 grain more than the starting load

George Roberts
07-31-2009, 02:45 PM
I am confused. Is the error in successive weighing of the same sample or is the error the spec tolerance?

I suppose a more precise scale is available.

Phillip Allen
07-31-2009, 02:50 PM
successive weighing of the same item

Captain Blight
07-31-2009, 03:05 PM
My old Ohaus balance scale wasn't accurate to more than a tenth of a grain, and I never even had a primer come loose. Honestly, unless you're worried about your next benchrest competition, you won't even notice.


A tenth of a grain is 1/4,375 of an ounce. You're probably weighing air currents, and I mean that literally. Glue up a little Plexiglass box to fit over the scale and keep the stray puffs of air from messing up your accuracy.

Phillip Allen
07-31-2009, 03:07 PM
Ohh common... 0.1 ?? means that much?

It's been a long time since I reloaded anything, but a typical load might have been 57 gr of whatever powder... now tell me that 0.1 means anything, and this was long before lectronic scales so you could never have measured it anyway.

plus or minus 0.2...PLUS the 0.1g accuracy guantee equals 0.3 grains...a starting load of 57 grains and a maximum load of 58 grains automatically limits me to a top load of 57.7 grains which I must assume is the maximum load

Phillip Allen
07-31-2009, 03:26 PM
I practice the best laboratory technique that I can...the 57 to 58 numbers were only convienient examples and don't refer to any specific loads/calibers/powders/bullets

I do not exceed reccomendations at all...I've been reloading since I was 16 years old (I'm 60 now) and have not had any accidents nor broken anything

the cannon ball that misses is not nearly as effective as the B-B that strikes the target

cathouse willy
07-31-2009, 05:36 PM
Phillip What are you loading that the charge is so critical? The scale can only be as accurate as the device used to "measure " the charge be it solid state or analogue. Theoreticaly the higher the cost the better the accuracy, couple that with the fact that most any device will show more errors at the edges of its capacity .What percentage of the load is the error? None of my loads require that much accuracy.

Phillip Allen
07-31-2009, 08:40 PM
These are open scales, eh? Little things, a breeze in the room, will cause some error in small amounts. I confess not knowing how much a 'grain' is. I've never done this sort of work.

But starting high school I worked with scales that were enclosed in glass, and meant to measure much smaller amounts. Maybe enclose your scales in some sort of barrier? If it's important.

Just a thought, I have no idea about what you are doing.

yep...the celing fan set on low will give me a false reading

Phillip Allen
07-31-2009, 08:41 PM
Phillip What are you loading that the charge is so critical? The scale can only be as accurate as the device used to "measure " the charge be it solid state or analogue. Theoreticaly the higher the cost the better the accuracy, couple that with the fact that most any device will show more errors at the edges of its capacity .What percentage of the load is the error? None of my loads require that much accuracy.

I want all my bullets to pass through the same hole...that may never happen but I'll get closer by being accurate in my loading

Pugwash
07-31-2009, 08:46 PM
Phil, it depends on what you're selling.

If it's coke then you want to be acurate, cokeheads get really fussy about weights. If it's weed then, meh!! take out a seed or two and it's all good.

:)

Phillip Allen
07-31-2009, 10:07 PM
I expect to hit a target that is roughly two minutes of angle at five hundred meters...with iron sights

Phillip Allen
07-31-2009, 10:10 PM
BTW, I have now cleared space to set up my old balance scales and will do tests as you suggest...

BrianW
08-01-2009, 01:05 AM
Let us know when ya start reaming primer pocket holes. Then we'll know your a loonie. :)

(I must confess to doing that, for awhile.)

I'd concentrate on bullet seating depth first. But I don't know if that works in the black powder world.

Phillip Allen
08-01-2009, 07:47 AM
Let us know when ya start reaming primer pocket holes. Then we'll know your a loonie. :)

(I must confess to doing that, for awhile.)

I'd concentrate on bullet seating depth first. But I don't know if that works in the black powder world.

I have to ream the primer pockets on military brass (.308)

BrianW
08-01-2009, 08:25 AM
I have to ream the primer pockets on military brass (.308)

I've certainly heard of the need to remove the crimp with military brass, although I didn't find it to be the case with military .45acp brass.

Are you separating the cases by weight yet? The internal capacity differences might be more of an accuracy issue that .01g.

Phillip Allen
08-01-2009, 08:45 AM
Brian, I've done all that at one time or another...even matched my primers by weight back in my teens

most is unnecessary but some DOES make a difference...however, and this is actually important, superstition works. By that, I mean, at a match it helps personal concentration to become a bit stilted in one's habits to prevent the mind from wondering and interupting concentration...such as: hold the rifle in exactly the same way even when walking to the firing line...take a certin number of deep breaths...fix eyes on some particular distant point for a few seconds and then ready to fire...what one does exactly is unimportant so long as he does it the same way each time

this also applies to loading ammo. if one has confidence in the ammo even by doing un necessary primer weighing, it is helpful in placing each successive shot

Bob Adams
08-01-2009, 09:41 AM
I expect to hit a target that is roughly two minutes of angle at five hundred meters...with iron sights

My eyes make it impossible for me to even THINK anout trying that!

Phillip Allen
08-01-2009, 09:57 AM
I don't have particularly good eyes...in fact they are poor...there are other consederations

Phillip Allen
08-01-2009, 12:09 PM
From a shooting site... (1 MOA = 1.047 inch @ 100 yards)
http://riflestocks.tripod.com/moa.html

at 500 yds 1.047 becomes a little over 5 inches for 1 MOA
and your at 2 MOA so double that we're now talking a little over 10 inches and
your 500 m is more than 500 yds, so... what is your target a pie plate, big pizza?
and with open sights? what gun are you shooting? and what kind of sights?

If it's a peep sight, what diameter hole would it have so that you dont see all of hells 1/2 acre when looking through it and only a circle of say 5 ft diameter around that pie plate?
You must have some tricks on this or am I going to have to do the math :)

I can't remember the exact size of the rams but they are a bit more than two MOA at 500m...they weigh about 55 pounds

look up sole sights to see what we use http://www.possibleshop.com/rifle-creedmore-sight.html

Krunch
08-01-2009, 12:12 PM
A tenth of a grain is 1/4,375 of an ounce. You're probably weighing air currents, and I mean that literally. Glue up a little Plexiglass box to fit over the scale and keep the stray puffs of air from messing up your accuracy.

+1

Or 1/70,000 of a pound.

As an aside, CapBlight, do you mean to tell me you RELOAD??? :eek:

Didn't you and I once duke it out here in the bilge over gun control?

Phillip Allen
08-01-2009, 12:17 PM
I close windows and close air vents and turn off fans before I weigh out powder or bullets...

Krunch
08-01-2009, 12:20 PM
I close windows and close air vents and turn off fans before I weigh out powder or bullets...

Yeah but do you draw the blinds? :p

Phillip Allen
08-01-2009, 12:22 PM
nope

Phillip Allen
08-01-2009, 03:26 PM
Winchester high wall chanbered in 40-65. I use globe front sights with various incerts

409 grain bullet and 60+ grains of black powder (havent's settled on a load yet)

Phillip Allen
08-01-2009, 03:52 PM
very much like it...

dmg
08-01-2009, 06:53 PM
Phillip

Any chance that your scale has to be recalibrated after you turn it off each time ? Mine seems to be a little erratic unless I do this. It only takes a minute or so.

That 0.1 gr might actually be a big deal, especially with a compressed charge, and the distance to target.

My rifle would only put 6-7 out of ten, on a 9" center until I got serious with the weights. With the powder within the 0.1 gr., and the 550 gr. bullet +- 0.1, I now put 10 for 10 in a 9" or less group.

Dave

Phillip Allen
08-01-2009, 07:01 PM
I generally sort bullets by weight and weigh the black powder charges.

I've now tested the elect scale against the balance and they read the same except the balance is more consistant...just like my original complaint

right now I'm loading some .45 Colt stuff and the Lyman manual has the starting load at 8 grains and the maximum load at 8.8 grains...gotta be careful. I think I'll change powders to give myself more latitude for errors

changing from Unique to 2400 powder
unique=8-8.8 grains
2400=15-17 grains

240g jacketed bullet

peterAustralia
08-01-2009, 09:47 PM
I worked in laboratories for 6 years

Your variation is due to air currents. Air currents will cause the balance to wander all over the place. This is why analytical balances have a glass box around them with a sliding door. To make a reading the door must be closed.

A lab balance will often read to 0.00001g

So build a box for your balance if you want accuracy. Cardboard is fine.

Add a small window with cellophane so that you can see the reading. Add a small door that can be opened and closed to allow you to add powder. If you want an even more accurate balance you can buy them, but first try the box first. This is used in EVERY analytical laboratory!

n peter evans

BrianW
08-02-2009, 12:17 AM
changing from Unique to 2400 powder
unique=8-8.8 grains
2400=15-17 grains

240g jacketed bullet

Don't have a loading manual handy, but I like that switch.

I bet there's no chance of a double charge with 15-17 grains, like there is with just 8 grains. Plus there's just something not satisfying to me about have so little powder moving around inside a big old case. Just changing the angle you hold the revolver is gonna change the way the powder lies in there, and how the primer spark travels over the load.

Phillip Allen
08-02-2009, 06:39 AM
I always use the bulkier powder when I can. The Unique is generally the powder of choice for the old colt with cast bullets and I was trying to keep things simple. If I switch to using 2400 with the cast bullets, I have to use heavier charges than I want to in my two revolvers...a colt copy and an 1858 Remington conversion (replica). I don't intend to shoot heavy loads in either of them

Paul Pless
08-02-2009, 06:49 AM
. . . switch to using 2400 . . .Smokeless??? :eek:

Phillip, I thought you were a committed BPMC shooter.;)

Phillip Allen
08-02-2009, 06:50 AM
I worked in laboratories for 6 years

Your variation is due to air currents. Air currents will cause the balance to wander all over the place. This is why analytical balances have a glass box around them with a sliding door. To make a reading the door must be closed.

A lab balance will often read to 0.00001g

So build a box for your balance if you want accuracy. Cardboard is fine.

Add a small window with cellophane so that you can see the reading. Add a small door that can be opened and closed to allow you to add powder. If you want an even more accurate balance you can buy them, but first try the box first. This is used in EVERY analytical laboratory!

n peter evans

Thanks Peter...and I am aware of wind currents and even my breath going the wrong direction. The problem starts when one is loading several hundred rounds at a time...these little scales aren't meant to be enclosed and aren't supposed to be accurate closer than 0.1 grain. When I suspect my balance scale has gotten bound (caused by dust in the bearings), I blow a little puff of air at it then let it settle again. I'm afraid any cabinet would slow the process down a lot. My loading room is a small room and I shut off doors, windows and vents when weighing powder...I don't even touch the counter the scale is sitting on during the process.

the electronic scale will weigh the same sample differently...I can take an average but that defeats the purpose of getting a faster scale.

I have already learned some better techniques and they work...I just have to polish them a bit more

Phillip Allen
08-02-2009, 07:07 AM
Smokeless??? :eek:

Phillip, I thought you were a committed BPMC shooter.;)

I am committed...but I shoot other firearms as well and have for many years. The black powder cartridge shooting is relitively new for me...only a few years

Captain Blight
08-02-2009, 12:47 PM
+1

Or 1/70,000 of a pound.

As an aside, CapBlight, do you mean to tell me you RELOAD??? :eek:

Didn't you and I once duke it out here in the bilge over gun control? Maybe, I don't remember. I've butted heads a lot here.


Yeah, I reload... or did, when I was shooting competition trap and some high-power silhouette back in the days when I was channeling Townsend Whelen and Jack O'Connor. My shoulder was more or less permanently bruised.

I'm the liberal you wish other liberals were like.

Phillip Allen
08-02-2009, 03:50 PM
Maybe, I don't remember. I've butted heads a lot here.


Yeah, I reload... or did, when I was shooting competition trap and some high-power silhouette back in the days when I was channeling Townsend Whelen and Jack O'Connor. My shoulder was more or less permanently bruised.

I'm the liberal you wish other liberals were like.

Man! I gotta get new glasses! what I read in your first line was "...buttered heads..."
it took me a second or two to go back and re read and end my confusion :)