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fishbone
12-07-2012, 08:02 AM
On another post on accuracy of powder measures someone questioned the accuracy of the scale used for checking. They claimed +/- 0.1 gr on beam scales.
Many years ago I used a Lyman beam, and recently bought, and now use, a Readding beam model. I just assigned great accuracy to them without question because of the beam design.
Are they accurate?
For my purpose in load development, repeatability is more important.
Any thoughts on this?

Centerfire
12-07-2012, 08:28 AM
Do you have a know, certified weight to practice with?
I believe RCBS has them and industrial scale companies.
Practice with the known weight and see how your scale reacts to build confidence.
Not sure but some beam scales may be adjusted to achieve zero on the scale.
Centerfire

Terry Balding
12-07-2012, 09:07 AM
They can be very consistent if you use good technique. I like to start with a light load and trickle up to the intended load. This gives me an ES of 10 or less in most cartridges.

vtmarmot
12-07-2012, 09:39 AM
I like my RCBS Chargemaster combo, but I check it against a beam scale frequently. I also grounded the metal frame to the heavy metal base of my reloading table. Never hurts to be totally anal about these things. The Chargemaster comes with two 50 gram weights and I calibrate it before each use, but I think now I will get a calibration weight kit so I can have smaller weights to cross-check both scales. I see them on Amazon for about 11 bucks. Oh, it got good reviews. I couldn't help myself, I just ordered it! Put it on my wife's card too. Maybe I'll wrap it for her for Christmas! Isn't multi-tasking great?

abintx
12-07-2012, 10:13 AM
On another post on accuracy of powder measures someone questioned the accuracy of the scale used for checking. They claimed +/- 0.1 gr on beam scales. Many years ago I used a Lyman beam, and recently bought, and now use, a Redding beam model. I just assigned great accuracy to them without question because of the beam design. Are they accurate? For my purpose in load development, repeatability is more important. Any thoughts on this?

As long as the instrument you're using can be calibrated, before use, to ensure that the reading you're receiving from it is accurate, it doesn't matter which type scale is being used. The key, is making sure you can calibrate the instrument to a known precise weight and have the ability to adjust it when it is off.

If you can't adjust it, you're always going to have to take the amount it is off, and account for the difference in your measurements. The biggest problem is when the difference starts bouncing all over the landscape. You can eliminate a lot of concerns with an instrument that allows it to be calibrated easily prior to use and provides a self-zeroing function.

For reloading, I like the RCBS Charge Master Combo 1500. It does all the things described above and turns reloading into fun instead of a chore. It's a little more expensive, but if you look at the current price plus rebate and the price one pays for a good beam scale, the difference in price might be very manageable. This site has always been a great source for a deep discount on the RCBS 1500: http://www.natchezss.com/product.cfm?contentID=productDetail&prodID=RC98923&src=exrbSrch To get the $75 rebate I added an item over $10.10 to qualify.

Here's a good video on the 1500 by Sinclair that covers many of it's features: http://www.youtube.com/watch?v=PckYE6K6sYY

The best price is found by shopping around. However, Natchezss is hard to beat.

Flat Tire
12-08-2012, 10:47 AM
I just got one of these. I am impressed.
http://www.accurateshooter.com/gear-reviews/gempro-250-digital-scale-review/

Boyd Allen
12-08-2012, 11:40 AM
One way to tell how your balance scale is performing is to repeatedly weight the same object. It the pointer does not come back to exactly the same place every time, you have issues to resolve. Scales, even new ones, benefit from tuning. Another little demonstration that can be instructive is to change the beam setting by .1 grain after you have balanced the scale, with something in the pan. One of the issues is that the beam moves so little with a .1 gr. difference. Parallax is another problem. There are workarounds, such as this. (not my video, but I have a similar setup) http://www.youtube.com/watch?v=ZCs0Y7HH2zA
http://www.youtube.com/watch?v=HMX4lq90Fy4
http://bulletin.accurateshooter.com/2012/02/tech-tip-use-mirror-and-magnifier-with-beam-scales/
http://www.youtube.com/watch?v=U57jnitmLP8

Fla mac
12-08-2012, 02:56 PM
I’m not that worried about the accuracy of my power scale, just that the will repeat each time I use them. Say you are working on a load that is between 34 and 36 grains. I start with 34 gr. on my beam balance scales (RCBS). Load as many rounds as I want to test, if this is a good load I stay with 34 gr. on my power scales. I don’t go to another scale and load with it. I don’t care if the scales you start with reads in “rocks” if you find a load that shoots good and it is 34 “rocks” use it. I think the repeatability of you scales is more important than the accuracy. I start on the low end and work up. Just my opinion.

john
Mims, Fl.

fishbone
12-09-2012, 10:05 AM
I feel my confidence in the inexpensive beam scale was right. Here's my take from the above posts.....
The knife edges must be sharp and clean.
A stable base
A needle added to the pointer for better resolution (A step farther would be magnification).
Elevate to reduce parallax.
Test with measuring the same wight to confirm repeatability.
Now, with the above being done, loads should be very uniform. Maybe not the exact weight recorded, but tuned to what was read out, and will be weighed to the same setting for the next loading.
To my thinking that should be a dead nuts weighing system. I am not loading to a stated weight, but to what shoots best and recording what the scale reads requiring me to always use that scale and set-up.

mike in co
12-09-2012, 11:14 AM
this can be very inconsistant with a reloading beam type scale...
you must touch the beam and getting it moving AFTER every add to the pan...the magnetic dampening resist movement....
very easy to be off a tenth or more if you simply trickle and let the beam come up by itself.

the gem pro 250 seems to be good...we need more feedback from users.

mike in co



They can be very consistent if you use good technique. I like to start with a light load and trickle up to the intended load. This gives me an ES of 10 or less in most cartridges.

mike in co
12-09-2012, 11:16 AM
this is not much of a check...both intruments are plus or minus 0.1...so sorta hard to check against each other.....the tool used to check the first tool must be MORE accurate THAN THE TOOL BEING CHECKED.
mike in co


I like my RCBS Chargemaster combo, but I check it against a beam scale frequently. I also grounded the metal frame to the heavy metal base of my reloading table. Never hurts to be totally anal about these things. The Chargemaster comes with two 50 gram weights and I calibrate it before each use, but I think now I will get a calibration weight kit so I can have smaller weights to cross-check both scales. I see them on Amazon for about 11 bucks. Oh, it got good reviews. I couldn't help myself, I just ordered it! Put it on my wife's card too. Maybe I'll wrap it for her for Christmas! Isn't multi-tasking great?

drumcorpschamp
12-09-2012, 05:26 PM
To be clear, I shoot long range benchrest. If I shot point blank, I suppose my methods would be different.

I did an experiment this afternoon using my RCBS Chargmaster, GemPro 250 and RCBS 10-10 scale. All 3 were set up and zeroed and were calibrated with their respective weights and procedures. The test was performed with N540 powder as it has the smallest/lightest kernels (about 5-6 kernels) per .1 grain of any of the powders I have on hand.

Test 1: 30 grains N540, repeated 3 times.
1.) Throw charge with Chargemaster.
2.) Weigh and trickle up to 30.00 grs. on GemPro.
3.) Dump charge in pan of 10-10 set at 30.00 grs. Beam centered exactly on zero.

Test 2: 30 grains N540, repeated 3 times.
1.) Throw charge with Chargemaster.
2.) Weigh and trickle up to 30.00 grs. on 10-10.
3.) Dump charge in pan of GemPro. Scale read exactly 30.00 grs.

The 2 above tests were repeated with charge weights of 43.00 grs. and 65.00 grs. Results were the same as with the first two tests.

The scales were checked after the tests with their respective calibration weights and none had changed.

Conclusions:
The 10-10 is a great scale. So is the GemPro. The Chargemaster is perfect for throwing charges quickly, but not as accurate (+/- .1 grs. or more) as the other two scales.

I have been using the GemPro to verify and trickle to the proper weight as it is takes less time to do than with the 10-10. If I were in a situation with no electric power, I'd be perfectly served weighing charges with my 10-10 only.

Jerry

mike in co
12-11-2012, 10:42 AM
jerry,
nice report...
the issue with the 10-10 is not so much its ability to weigh, but the user.
people that trickle seldom move the beam after adding powder....instant error.
try the test with a large kernel.
do the test in reverse...10-10 with a large kernel..then on the gempro....
mike in co

To be clear, I shoot long range benchrest. If I shot point blank, I suppose my methods would be different.

I did an experiment this afternoon using my RCBS Chargmaster, GemPro 250 and RCBS 10-10 scale. All 3 were set up and zeroed and were calibrated with their respective weights and procedures. The test was performed with N540 powder as it has the smallest/lightest kernels (about 5-6 kernels) per .1 grain of any of the powders I have on hand.

Test 1: 30 grains N540, repeated 3 times.
1.) Throw charge with Chargemaster.
2.) Weigh and trickle up to 30.00 grs. on GemPro.
3.) Dump charge in pan of 10-10 set at 30.00 grs. Beam centered exactly on zero.

Test 2: 30 grains N540, repeated 3 times.
1.) Throw charge with Chargemaster.
2.) Weigh and trickle up to 30.00 grs. on 10-10.
3.) Dump charge in pan of GemPro. Scale read exactly 30.00 grs.

The 2 above tests were repeated with charge weights of 43.00 grs. and 65.00 grs. Results were the same as with the first two tests.

The scales were checked after the tests with their respective calibration weights and none had changed.

Conclusions:
The 10-10 is a great scale. So is the GemPro. The Chargemaster is perfect for throwing charges quickly, but not as accurate (+/- .1 grs. or more) as the other two scales.

I have been using the GemPro to verify and trickle to the proper weight as it is takes less time to do than with the 10-10. If I were in a situation with no electric power, I'd be perfectly served weighing charges with my 10-10 only.

Jerry

drumcorpschamp
12-12-2012, 10:04 PM
jerry,
nice report...
the issue with the 10-10 is not so much its ability to weigh, but the user.
people that trickle seldom move the beam after adding powder....instant error.
try the test with a large kernel.
do the test in reverse...10-10 with a large kernel..then on the gempro....
mike in co

Thanks Mike,

I always give that little nudge to a beam scale. Agree....only way to do it.

Have also found with the GemPro that when I just trickle up to weight and do not give the pan a lift and set it back on the stage, I usually wind up overweight. Best and quickest results come for me by lifting the pan when I'm within a kernel or so, let the pan down and read the number and repeat until weight is reached. Actually took me much longer to type these couple sentences than to weigh the actual charge.

I think doing the test with large kernel powder would only show how difficult it is at times to get the beam scale or the digital to settle right at zero because some of those kernels can weigh .03-.04 grains. I'm satisfied and convinced with the results I attained.

Jerry

Carver
03-28-2013, 07:24 AM
I have a bench scale for sale. I hope it would be the best for your need. here I have some information about the " Bench Scale " . Its 500lb/0.1lb legal for trade. Bench scale It features a stainless steel 18"x18" platform. In an affordable prices.
Ntep Scales (http://www.elitescale.com/ntep-certified/?sl=EN)

Vern
03-28-2013, 06:09 PM
I used to think the electronic scale I was using may not be any more accurate than +-.1 but figured that didnt matter as long as it was repeatable.
I was wrong. I started weighing bullets one day and then went back and started to check then ones I had weighed..... oooooppppsssss.
I found that if I took one bullet and weighed it waited a while and reweighed it and kept doing this with several different bullets then they could weigh +-.1 for the same bullet. And yes the room was perfectly set for temp breeze and the like.
This was an RCBS scale from a couple of years ago and a new one also.
FWIW

alinwa
03-28-2013, 10:04 PM
I have, or have had 5 balance beam powder scales and 7 electric ones. I didn't find one that was a marked improvement until I got a MMX-123 or whatever they are, then AND ONLY THEN, could I actually visually and easily and repeatably see one single kernel of powder.

Put it on,

take it off,

put it one,

take it off,

go have lunch, come back, put it on....

and SEE it.

From this single thing I easily found single digit ES and instantly relegated $1000.00 worth of tools to the junk heap.

for those of you who don't want nor need single digits, please refrain from muddying the waters with irrelevant commentary about "winning with charges dipped with a spoon."
al

Boyd Allen
03-28-2013, 11:50 PM
For those of you on a tight budget, I have spent considerable time with the same model scale that Al has, and a Gem Pro 250 that costs less than half as much, and while the exterior quality of the Gem Pro is not in the same league as the more expensive scale, its weighing performance seemed to me to be. Also, I have read a comparison test that agreed with my conclusion. They both are strain gauge type scales and as such can suffer from the same sorts of issues. The next step up is a scale that works on the principal of magnetic force restoration, and those are twice as much as Al's scale. You may find this to be of interest. http://bulletin.accurateshooter.com/2012/09/digital-scale-comparison-gempro-500-ay123-sartorius-gd503/
Although the scales compared are not exactly the same as those that we have discussed they are very close.

alinwa
03-30-2013, 02:13 PM
Chronographs.

Back when Henry Childs first spent time here he and others did a bunch of chronograph testing. And a bunch of engineering types discussed and weighed the "why" and the "how" of chronograph accuracy. I've still got photos and data-sheets stored in my computer, stuff it'd take me days to decode but stuff I understand just well enough to trust the veracity of the guys sending it.

I also did some "testing" my way.

And I've a fairly good handle on "luck" and the laws of averages.

Bottom line, if you've a chronograph of any sort and you consistently produce loads that are "really close together" velocitywise...... and if other loads are consistently "NOT really close together," velocitywise.........


Then worrying about the "accuracy of your chronograph" is kinda' like mistrusting your compass.


Just how lucky would you have to be to string together a bunch of 6-digit ES spreads? Shucks, if you can, and it's luck, then you better go buy a lotto ticket. Better yet, bring your Model 94 30-30 to a group match and let the wind "blow 'em in!"


opinionby
al

glp
03-31-2013, 02:13 PM
for those of you who don't want nor need single digits, please refrain from muddying the waters with irrelevant commentary about "winning with charges dipped with a spoon."

Yes but we need a thorough test done and reported here on Chronograph accuracy.

I use the two lb coffee can method...

Clean and dry a wide mouth Folgers plastic can

Fill arf with H4198

Prep cases

Pick up a case and scoop through powder till full

Bang on table to settle

Empty till powder is halfway up neck

No stinkin scales !!

vargetman
03-31-2013, 04:56 PM
Francis,

What happened to MikeinCo. I must be getting old as I didn,t/haven,t missed him.

John

Vern
04-01-2013, 05:38 PM
Wilbur posted a week or so ago that Mike had been temporarily booted for improper conduct. If you can imagine that from Mike.

vargetman
04-01-2013, 06:06 PM
Thanks Vern, I missed that post. Not that I really missed Mikes post or replies. Hopefully he will learn to play nice the next time.

Edwin
01-21-2014, 04:12 AM
I think now many companies offering a range of scale with low precision level and accuracy. I have bought one from EBay in $100 and it gave me accuracy up to 3 division (http://www.scaleforless.com/Floor-Scales-Industrial-Scales/b/6339955011/). Its enough for me to get accurate result up to that limit. And there are a range of scales with different latest features according to your needs.

jim1K
01-21-2014, 07:43 AM
This whole thread has not mentioned one scale that is capable of weighing .005. How can you have any idea what the scale your using is capable of weighing,you are guessing. Most don't need the accuracy needed at long range. If you need or want a scale capable of .01 better you need a GD 503 or better……… jim

Pete Wass
01-21-2014, 10:38 AM
I think most of us want our barrels fitted with as little error as humanly possible, don't we? That being the case, why would anyone disregard the same kind of accuracy when it comes to the key component that makes the rifle perform consistently to the same degree of accuracy? If exact loads don't matter then , perhaps, exact fitted barrels with dead nuts chambers and crowns don't matter so mush either. Personally, I believe that everything matters and some folks get lucky sometimes. That last little bit of accuracy is always important, rather it's in the construction of the rifle or the ammo that is fed into it. To say otherwise has never made sense to me.

I have seen a lot of great shooters win matches and break records. I have also seen the same shooters not do so well. I have always wondered how much better they might have done with perfect ammo.

Pete

Boyd Allen
01-21-2014, 11:26 AM
I think that it all comes down to the game that is being played. The longer the distance, the more important low ES becomes. I believe that accuracy comes from multiple factors, and that while all are important, that some are more than others, and that how they are weighted depends on the circumstances. One of the best 1-200 yard rail gun shooters that I know of, uses powder that lends itself to being measured, and throws his charges. On the other hand, if there was a range around here where I could shoot 600 yards and farther, and I was planning to do that, I would not think of staying with thrown charges.

jim1K
01-21-2014, 11:37 AM
Powder weighing will help with low ES but it is a small part of the big picture…… jim

Edwin22
02-04-2014, 04:42 AM
It depends on you that how much you can pay for that scale. Because when you pay more you get best scale with accuracy (http://www.primescales.com/store/) and other features that you need. I have bought one from Walmart with accuracy up to .001 in just $50.

jim1K
02-04-2014, 12:22 PM
Edwin, Give me the make and model # of a scale you can buy for 50.00 and weigh with in .001 of what an oz. or a grain? a postal scale is useless for weighing powder……. jim

SGJennings
02-04-2014, 01:47 PM
Edwin,

You are either a troll or you are seriously misinformed.

alinwa
02-04-2014, 01:55 PM
no, he might be a ninja....

jim1K
02-04-2014, 02:01 PM
Edwin,

You are either a troll or you are seriously misinformed.

What or whom are you referring to?…….. jim

SGJennings
02-04-2014, 02:19 PM
Jim,

I was addressing who I addressed the post to in the salutation. You know...where it says "Edwin,".

jim1K
02-04-2014, 03:59 PM
Sorry, i didn't see that…. the lights are getting dimmer ……… jim

SGJennings
02-04-2014, 04:02 PM
No problem, Jim. Have recently started having to wear reading glasses for some tasks myself.

-- Greg J.

jim1K
02-04-2014, 05:10 PM
Greg, It's way past that point, I hope to get this year in shooting BR……. jim

SGJennings
02-04-2014, 08:45 PM
Jim, you have a handle on the precision reloading gig, what scale are you using?

jim1K
02-05-2014, 08:05 AM
Greg, A GD 503 with a electric trickler, i can and do hold .01 grain. I throw a light load with a powder measure and trickle up to weight. You have to remember i shoot 1000 yds.
so things are a little more critical……. jim

SGJennings
02-06-2014, 08:39 AM
Hi Jim,

Thanks for the info. I know that you're successful in the long range game. I appreciate you taking the time to spread the wealth.

I'm going to play some in the longer range games this year. Thus, my question. Of course, I might have played "straight man" to get a good answer out there anyway.

When I load for the short range game, I use my ChargeMaster and I'm happy. I do have two pans that I've worked over to be as close to the same weight as I can manage as measured on my tuned up RCBS 505. Charging one pan while I'm trickling with the other speeds things up.

The few times that I've loaded for longer range, or I have wanted to eliminate the powder charge variable for some reason, I have done much as you describe. I throw the charge light with the ChargeMaster, then trickle up to weight with an old-fashioned thumb-and-forefinger RCBS trickler and the aforementioned 505. I use a web cam mounted in front of the 505 to help with magnification and paralax. Might not be as good as the high-dollar scales, but I've been happy.

I might spring for one of the good scales one of these days. Right now, with two kids in college and pushing to stick to my retirement savings plan, my toy purchases are limited.

jim1K
02-06-2014, 09:30 AM
I would have your scale tuned and it will be better, i noticed the difference from a factory scale. You could look up a thread on tuning it yourself, i think Boyd did it. An Omega powder trickler is a plus also. If you can keep it under a .1 you will be fine for now. Annealing and neck tension are critical so i would give that a lot of attention. Bullets are a huge deal also,trim and point and bearing surface +-.001. There are more but i don't want to get into that till you understand and address these point first……… jim

jim1K
02-06-2014, 10:49 AM
I kind of missed the part about the scale, You are on the right track. I would invest in the Omega trickler,they work great and very fast……. jim

SGJennings
02-06-2014, 10:54 AM
Hi Jim,

Thanks again for the help. I appreciate it very much.

My scale is tuned. I think it's the same guy that makes the Prometheus unit did it. I bought it second hand, so I'm not 100% sure.

I have a Ken Light annealer. I'm not very good in using it. Any tips that you might have about setting temperature would be greatly appreciated. I've used the vice grip method that Ken recommended. I'm just not confident about it. It's also a pain in the patootie to adjust the torches each time.

I read that you polish the inside of your necks. How do you do it?

I've been using the Imperial unit to lube the inside of the necks as part of my longer-range rounds. Is that what you do?

I have not been trimming or pointing? Can you recommend specific tools?

I have been sorting on base-to-ogive. I use a Redding neck sizing bushing of the bore size and a dial indicator in a small fixture. It seems to work. I first started to use the Sinclair hex nut comparator rather than the Redding bushing, but it was too tall for the fixture.

The last batch that I did were Berger 6mm 90 grain BT. On the base-to-ogive, the distribution was bi-modal. I found that very interesting. The lower had a lot more bullets in it, but there was enough in the upper that I used them for my initial sight in and recording come-ups.

Best regards,

Greg Jennings

jim1K
02-06-2014, 11:24 AM
I used the vice grip deal, Templac…… ended up on a visual method. Darken the room,and set the dwell time to you just see a fait glow start. I only use one torch and i set the pencil point 1" long,that way my heat is close to the same every time. trimming and pointing i use Hoover's set up….. Sorting, Bearing surface not base to ogive, see if Mark King still has the Bearing surface comparator,this is the best method. I use a force indicator to seat the bullets and keep the in sets. I never use lube in the neck to seat the bullets. PM me if you need more info……… jim

Joe Maisto
02-09-2014, 06:53 PM
Francis,

What happened to MikeinCo. I must be getting old as I didn,t/haven,t missed him.

John

Me too...getting old .....

ekp
02-10-2014, 08:36 AM
I recently started a method that I like using the 10-10 scale. I touch the empty pan to get it to oscilate and trickle up my charge. I then see the needle go above and below center until it reaches my charge weight. I then touch again to stop it and check where the needle settles. This to me makes sense as the accuracy will vary depending on how the knife settles in the scale. The beam can become off centered putting it too close to on side or the other.

SGJennings
02-10-2014, 12:15 PM
With a 505 or 1010 scale that's been kept in shape or tuned up, you'd have to be pretty sloppy to not beat 0.1 grain accuracy.

ekp
02-10-2014, 12:16 PM
that is a fair method,IF plus or minus 0.1 is good enough for you.
for some of us it is not.

To clarify, I drop a charge a little light with a Belding and Mull powder measure then trickle up with the oscillation as previously mentioned. I am dead nuts when finished. I find the pan moving until then makes the beam more responsive.

DaveT
02-10-2014, 04:16 PM
I thought I would jump in here and throw in my two cents. After talking to a gentleman who tunes beam scales, we both agreed that you should throw a few tenths under and trickle up until the needle lines up, but doesn't go past. This way the charge is done in one pass and you're not waiting until the needle settles, it's all in one trickle up to zero, if I go past I dump and do over, make sense.
Dave T

Boyd Allen
02-10-2014, 04:41 PM
From your post, I wonder if you have spent much time with a tuned balance. Recently I bought an older RCBS 505 and tuned it. Then I set it up with a web cam on the end of the beam and balance reference mark, so that the camera was about a half inch from the scale. After carefully zeroing the scale, I dropped a single piece of Varget in the pan, and saw a small deflection, and continued with additional pieces of Varget, each moving the scale progressively farther from zero, then I set the scale to 0.1 grains, with the four granules in the pan, and it came back to zero. Somehow I doubt that your remarks about balance scales and what they are capable of, are based on any sort of experience with a really well tuned one, and what can be seen with the use of a web cam, so that there is no possibility of parallax, and the image is greatly magnified.

DaveT
02-10-2014, 04:51 PM
Boyd, I use a tuned beam scale, would you agree with my method of trickling up until the needle lines up and not going past?
Dave T

ekp
02-10-2014, 04:53 PM
My wife and I visited a museum once that had a handmade double pan balance made in Germany. It was in a glass case so as to protect it from any breeze from disturbing it. It was a work of art and i would suspect it capable of extremely good accuracy.

Very interesting discussion but as my father once said "Everyone to their own taste" said Mrs O'Leary when she kissed the cow.

Boyd Allen
02-10-2014, 08:50 PM
Dave, yes.

alinwa
02-10-2014, 09:40 PM
My wife and I visited a museum once that had a handmade double pan balance made in Germany. It was in a glass case so as to protect it from any breeze from disturbing it. It was a work of art and i would suspect it capable of extremely good accuracy.

Very interesting discussion but as my father once said "Everyone to their own taste" said Mrs O'Leary when she kissed the cow.


Now waitaminnit....... I thought Mrs O'Leary burnt Chicago down with a cow....??? (apocryphally)

I think your Dad was mixing metaphors :) I like that...

My Dad used "ever'body to their own notion said the old lady when she kissed the cow"

jim1K
02-12-2014, 06:49 AM
I can safely say that a tuning of the balance beam is better, the way you use it will make it more consistent. The point is 4 kernels of Varget is a tenth? I only use Varget to fire form and i do weigh the loads on the GD 503 and i do hold them fairly close. I do know with RL-15 the size difference of one kernel can be weighed on the GD503……. jim

SGJennings
02-12-2014, 08:38 AM
the part you missed is
THE SCALE IS DESIGNED FOR PLUS OR MINUS 0.1..
no matter how good your technique...
on a bad day even worse than plus or minus 0.1....

without a BETTER scale to check your work, you do not KNOW the actual accuracy of your work.

it is simple math......

it is why others use scales that are plus or minus 0.02 or less....

You are confusing resolution and precision. The resolution on the 505 beam is 0.1 grain. One in decent shape is considerably more precise than that.

As you say, you do have to have a scale with better resolution and at least as good precision to verify it. I do. There are benefits to working next door to a research laboratory.

For an easy, practical test, clean up a 505, set it up carefully, set it for X grains of powder, drop X minus a skosh, trickle up to it watching the zero line carefully. I'd suggest using a magnifying glass and something to eliminate paralax. I use a web cam. You also need to use a wind box.

After it settles in as close to X as you can get, drop one kernel at a time till you see movement. Let that movement settle out. If your 505 is like mine, it will settle to a minutely different spot. You now have a pretty good approximation for the practical precision in units of kernels for your powder. After all, we're weighing kernels of powder, not nanograms of unobtanium.

Boyd Allen
02-16-2014, 12:57 PM
I think that for most purposes actual load adjustments, for tuning, of .1 gr. are small enough, given the nature and number of other variables that come into play. What I am looking for, which in no way disagrees with your post, is something that I can see when repeatedly weighing the same thing. I would like the pointer to come to rest in the same place, time after time, and as you mentioned, a web cam gives a much better view of what is going on. These inexpensive scales can be made to work much better than they did when brand new. One little tip, I believe that the primary cause of blunted areas on the knife edges is lack of attention when the beam is placed on the scale. It is easy to get in a rush and come down on one of the agate retainers. Now, I take the extra second to put the far end in, forward of it's final position, and slide it all the way to the back before rotating the beam so that the front knife edge comes into position in its agate support, missing the front retainer. Then, after finishing the assembly, I center the beam so that the ends of the knife edges do not rub.

jim1K
02-16-2014, 06:48 PM
Stool, I learned that i move one thing at a time to see if there is an improvement. When it came to powder, i started with a a RCBS digital scale i shot in 7" i used a 505 a little better not much. Went to a tuned scale much better, groups were smaller and with the GD503 and annealing, bullet trimming and pointing and a Juenke machine and seat depth measurement more precise and a seating force indicator the groups dropped to the 2's @ 1000 it is a sum of all parts. Now we come to barrel quality…………. jim

Boyd Allen
02-16-2014, 06:49 PM
I was not talking about variation of charge weight within loads that are shot on the same target, but rather the target weight to which they were loaded. Given that long range is preloaded, and conditions can vary from what was predicted, I would guess that two perfect set of loads that were intentionally loaded .1 apart, in the center of a node, would be hard to distinguish if each were shot on a separate target. I fully understand the concept of keeping the variance of charges to the absolute minimum to avoid one source of vertical dispersion in groups shot at long ranges.

John Kielly
02-16-2014, 08:12 PM
Isn't the circumstance that, by precisely weighing powder, a 1000 yard shooter can position his load at a predetermined point in a node such that it will suffice for changes that he might predict for the day. To the contrary, a 100/200 yard benchrester's metered charge is already absorbing a higher degree of a bullet's sweet velocity range such that he can flip out of that zone as conditions change.

Disclaimer: Not a short range benchrester.

jim1K
02-17-2014, 12:11 PM
Boyd, A +- .1 variance with in a given load is easy to see if the gun is capable of zero groups at 100 yds. but you better have all your ducks in a row everywhere else……. jim

ekp
02-18-2014, 11:18 AM
This is the reason I like the pan to oscilate while tricklng up. I do not have to tap the pan until it looks like it is on my chargeM I then just touch the pan to stop it.

jim1K
03-11-2014, 07:30 AM
If you guys are looking for a very good scale at the right price, a A&D FX120i sold out of Canada; Cambridge Environment Products Inc. 420.00 and it is magnetic force registration and is guaranteed 5 years. Best price i could find down here is 650.00……… jim

Pete Wass
03-11-2014, 10:46 AM
Some great LOOKING laboratory Balances on Ebay in the $200. range, made in USA and with a guarantee. I think one needs to look at Lab Balances for better accuracy. They have a covering around them with movable doors that shield out drafts, of one thing and I believe their weighing mechanisms are of higher quality.

Pete

jim1K
03-11-2014, 01:41 PM
Pete, The one i made reference to was accurate to .02 and is weighing in 1 second and they have the draft shields and is guaranteed for 5 years……. jim

Lee Martin
03-11-2014, 01:59 PM
I recently bought a GemPro 250 for $120 NIB and am pleased. I'll have to see how it holds-up but so far so good. Now are there better 0.02 scales out there? Of course there are, but for the price I really like the GemPro.


-Lee
www.singleactions.com

jim1K
03-11-2014, 04:40 PM
Lee, that is .02 not .2, the GD503 is .005 but cost 3 times what the FX 120i does with the same Magnetic Force Registration as the GD 503. It's the real deal, the GD 503 is certified and the weight and the FX 120i isn't and you pay dearly for the certification you don't need. A 100g. certified weight is 125.00 and the same weight with out the certification is 19.55… jim

Lee Martin
03-11-2014, 05:56 PM
Jim, as noted the GemPro 250 claims resolution to 0.02 grains. From what I can tell, including trickling 1 granule at a time, it seems pretty good. There are better units out there of course. My undergrad in chemistry exposed me to a few of them. But for $120 the GemPro gives me all I need from a scale.

-Lee
www.singleactions.com

jim1K
03-11-2014, 08:01 PM
Lee, A friend just sold his Gempro to get the FX 120i, way faster and they don't wonder with the Magnetic Force Registration. That is a 1000.00 unit top shelf for 400.00. You can't buy the the GD 503 any more……. jim

DaveT
03-11-2014, 09:38 PM
I have been using a FX 120i for several months now, it has replaced my tuned beam scale and I ain't going back, it is a very impressive scale, fast, accurate and repeatable.
Dave T

DSM
03-11-2014, 11:37 PM
I just received my A&D scale and you really can't compare it against the GemPro.

I used the GemPro 250 for about two years and it wasn't bad. It was accurate, drifted occasionally and pretty reliable. It had to be on 24-7 to get consistency out of it. During a loading session, 50 rounds...drift was experienced 2-3 times. Hit the tare button and back to normal. In all honesty, I don't think hitting a tare button constutes a bad scale. In the A&D manual, it specifically says to hit "re-zero" key before each weighing to eliminate possible errors.

The main reason for going to the FX-120i is speed. The GemPro would take 3-5 seconds to register anything dropped into the pan. So when getting close to charge weight...it was a constant cycle of drop 1-2 kernels, wait, drop 1-2 more, wait, repeat and hope its not over. The FX is insant and consistent when weight is removed and set back on.

With the GemPro...it took usually 2 kernels of R15 to move .02, maybe three depending on size of a kernel. Certainly would not register 1 kernel of R15.

All in all, the gempro will get you by...as long as its a good one, lol. I've read guys getting turds and sent them back for a replacement. One nice thing is, CS is great on them and will replace the scale if you encounter any trouble. The manual sucks though...there is a good YouTube video on scale calibration...find it and follow it.

Dick Grosbier
03-13-2014, 06:19 PM
I use the two lb coffee can method...

Clean and dry a wide mouth Folgers plastic can

Fill arf with H4198

Prep cases

Pick up a case and scoop through powder till full

Bang on table to settle

Empty till powder is halfway up neck

No stinkin scales !!

Greg
I prefer the Maxwell house cans.

Dick

Harold M
03-19-2014, 12:14 PM
I have recently purchased a GemPro 250. Yesterday I observed something interesting. To make a long story short, static electricity in the wind cover, pan, and tweezers, all plastic, caused the registered weight to change. Wiping all the above with a dryer sheet fixed the problem.

Harold

jim1K
03-19-2014, 01:31 PM
Stool, I like the price of the A&D FX 120i, it has to be the best deal on the market and having the magnetic force registration is a plus for sure. I use a GD 503 and i do +-.01 and have speed that DSM talks about, do you want to load or sit around and watch the bumper rust ………. jim

alinwa
03-19-2014, 08:45 PM
Static electricity is the bugaboo of all sensitive electronic systems. Do some searches or order some electro-tech catalogs to see reams of information. At the very least the scales must be set up on a neutral surface and have bleeder lines, and you need to keep yourself bled off to keep differentials at a minimum.

Dryer sheets are perty cool. They work by smearing the unit with electrically conductive goop which allows the liddle electronical bugs to scamper off into the surrounding environment, evening out potentials

adamsgt
03-20-2014, 12:24 PM
Lee, A friend just sold his Gempro to get the FX 120i, way faster and they don't wonder with the Magnetic Force Registration. That is a 1000.00 unit top shelf for 400.00. You can't buy the the GD 503 any more……. jim

I believe the $400 price is only available at Cambridge Environmental, which is in Canada. Their web site says their posted prices are in Canadian dollars. Anyone know how the US dollar and Canadian dollar compare these days? I assume that if you use a credit card to purchase the scale that the credit card company will do the conversion as appropriate.

jim1K
03-20-2014, 04:02 PM
I believe DSM had one shipped to him with a weight for 425.00. I may be off a little on it but i think i'm close….. jim

adamsgt
03-20-2014, 04:24 PM
ordered one. I had submitted an email to Cambridge requesting some info and they called me back. Didn't take much talking to get me to drag out the plastic. Yippie, another gadget. :D

jim1K
03-20-2014, 05:08 PM
You got a deal for what they cost down here……. And you got a quality scale …. jim

jim1K
03-21-2014, 10:14 AM
Stool, You can not buy a GD 503 anymore…… The FX 120i does use the same magnetic force registration as the GD 503. So it makes a very good unit compared to anything at the 400.00 price range,The best price down here was 650.00 + shipping. Accuracy to.02 and in 1 second. no more wondering…….. jim

GerryM
03-22-2014, 02:56 PM
Ahh the cans you both like the can method?.
Did you learn that from GUY GREEN? That's what he did a lot.

Dick Grosbier
03-22-2014, 04:08 PM
Ahh the cans you both like the can method?.
Did you learn that from GUY GREEN? That's what he did a lot.
Guy Green?
Gerry, do you really think anybody here besides you and me goes back far enough to remember Guy? Admittedly it does seem like yesterday he was around.
Dick

adamsgt
03-27-2014, 02:19 PM
is on the way. Checked my credit card today and it was posted for $425.00. They said they don't charge until the product is shipped. The guy I talked to said that they truck the stuff over the border and then ship common carrier from there. Should get it by next Wednesday.

Decided to take inventory of my scales. So now I will have, in addition to the FX 120i, an Ohaus Navigator scale, an Adam HCB 123 scale, a RCBS Chargemaster and a Lyman 1200 DPS dispensers, Dillon terminator, a Cabel's XT 1500, RCBS 1500, JS-VG digital, and a Ohaus 5 0 5 beam scale. Man, how did I get into this? What's that old saying, a fool and his money are soon parted. :eek:

GRV
03-27-2014, 05:14 PM
Scales have had a price increase, now $525.00 without shipping.

Nalson
04-21-2014, 02:26 AM
If you calibrate your scale with known weights before you get any measurement you get consistency in results (http://www.scaleforless.com/Brecknell-HS-250-Electronic-Physician-Scale/dp/B00BEDTSV4). And there will be a low chance of error. And in digital scale you must set it to zero before getting any measurement.

HFV
04-23-2014, 03:37 AM
Some of us in the southeast still use the "ole trusty tobacco scale" balance beam , and a 5lb check weight.

ThisGuy
05-15-2014, 01:39 AM
Scales have had a price increase, now $525.00 without shipping.
It is not a tough job to find cheap scales. There are many commercial scales (http://www.myscalestore.com/) stores providing their products at affordable prices. Shipping may be charged but still we can find cheap scales. Just Google you query and you will see stuff with different price lists.

Uthink Uknow
05-15-2014, 06:37 AM
Only two different letters in troll and stool.