Balance Scales - Improving precision?

[higginsdj]

OK, so my Dillon Balance Scales are accurate to +/- 0.1gn - I can live with that. So my aim is to improve their precision from charge to charge.

Step 1 - Take the user out of the picture - remove parallax errors.

http://www.david-higgins.com/fullbore/i ... camera.jpg
http://www.david-higgins.com/fullbore/i ... screen.JPG

I have used an old home security CCD camera setup and added a needle point to the end of the Dillon scales beam. From a zero perspective I have found, so far, that the scales repeatability is approx the width of the line which equates to around +/- 1 kernel of AR2208. Resting my hand on the shelf on which this all sits is also enough to deflect the point 1/2 the width of the line.

Does anyone else use this type of setup (camera and beam scale)? Any additional advice on improving the charge to charge repeatability precision?

To date it takes me about an hour or so to load 24 rounds (90%+ of that time just measuring out the charge). I'm going to invest in an Omega Powder Trickler and with this camera setup I am hoping to speed things up considerably.

Since my Savage Model 12 F/TR in 308 was 'fixed' I have to say that with my handloads (so far) I am very pleased with the results - 1/2MOA or better vertical groups at 800m. Now all I need to do is learn how to read the wind

Cheers

David

[Chris S]

G'day Dave,

I use the Handy Viewer device that's made by the same mob
that sells the Omega trickler. There is a short video on their website
showing how it works, just a simple perspex prism really.

cheers, Chris

[bsouthernau]

I have found that I can eliminate parallax errors by viewing the balance with my eye at the same level as the beam. Guess that doesn't give you the same hit if you're a gadgetry addict.

Barry

[Barry Davies]

David.
An hour or so to load 24 rounds?? That's time consuming.
A good ( expensive ) set of digital scales capable of repeat loads to within 0.02 grains ( one granule ) will weigh out at least 2 per minute and with a good thrower -- 3 per minute.---that's 8 to 10 minutes to weigh your 24 rounds and another 5 minutes to press them. Beats the heck out of an hour.
I use A and D model FX-120i capable of 1/1ooo gram ( 0.02 grains ) They are fast and accurate but not cheap.
No guess work, No drudgery. Just pure accuracy.

[TTBS28]

Hello Barry,

Can you please tell me where you bought your scales from? Have done a bit of very quick checking on the net and they come for around $500-00 to $700-00 on US sites but with a 110V adaptor. Did you buy locally OR buy off-shore and change the adaptor when it arrived?

Have had 3- 4 cheapie scales from $20-00 through to $80-00 that are battery operated and none of them are reliable enough for this sort of accuracy - disappointing! They keep fluctuating in readings and have to be constantly re-zeroed to get even close to the truth. Confidence is lost very quickly.

Look forward to hearing from you.

Regards.........Jeff. Roberts.

[Barry Davies]

G'day Jeff.

Purchased from Bendigo Scale Co.

Look up A and D scales on google, there are various dealers around the country. Shop around as prices vary considerably. Going price is about $1100.
You will buy cheaper from US but run the risk if anything goes wrong or if it gets damaged in transit

Exceptionally good scale with more bells and whistles than you need but next model down is 0.01 grams ( 0.2 grains ) which is a bit course.
Response time is capable of being set from slow ( about 4 secs ) to fast ( about 0.5 secs )
Not cheap but takes the drudgery out of loading if you do a lot --as I do.

[TTBS28]

Thanks Barry,

Will have a serious look at it now - fed up with the guess work that is going on lately with what we have.

Hope it is of interest to others as well.

Regards.........Jeff.