Help! RCBS 304 scales

[LDC1982]

right I'm just getting ready to start reloading for .223. I purchased a nice set of rcbs 304 scales off of this site and am struggling to get them to consistently return to zero.

 

Here's what I've done so far. Set the two beams to zero and the dial to zero, I have then adjust the knob on the left until the needle on the right points to zero. I then tap it a couple of times to make sure it returns to zero, which it does.

I then add a 20 grain check weight, select the 10 grain on the bar then dial in 10 grains it takes 20.1gr to return to zero. ( I don't know if that is within the tolerance of the rcbs check weights or not?) I then remove the weight reset the bar and dial to zero and I'm a couple of tents off zero each time.

 

Can anyone offer some helpful advice of how to set these scales up to get a consistent return to zero.

 

I'm guessing that these are fairly old scale but seem to be in good condition. Is there anywhere to get them serviced in the uk?

[MJR]

Why select 10gn on the balance bar when you can select 20?

Is the weight of your check weight accurate?

I didn't like the way the pointer end of the scale can hit the stop if you lift a thrown powder charge quickly off the scale so I fitted a small self adhesive pad to the stop to cushion the seat.

[gunner]

Hi there , im not familiar with this exact scale but think mines similar 505 i think , can you zero it and try something else like a bullet ? Then see if it returns to zero . But it might just be it kind of re-zeros it self once a weight has been applied ? 1-2 tenths of a grain isnt huge but as long as it consistently returns to 1-2 tenths out then i wouldn't worry too much ! My rcbs has a tendency of sliding left to right where the pivot points are , if i move the to one side fully , zero it then tap it over about 2mm to the other side there's about .3 - .4 of a grain difference !!! Point is i dont think hardly any sub std scale are perfect !

There was a guy on here Who tunes them VerY well , foram names 1066 but hes been asked a number of times by me and others to tune ours but hes just too busy

[John MH]

If it does not return to zero it will not be consistent. The 'actual' weight indicated in grains is not as important as getting the same each time, if its a couple of tenths different each time your charges will not be consistent. If its always 0.1 grains high then thats not a problem. Contact 1066 and get them serviced.

[LDC1982]

thanks guys i'll play about with it over the coming days and see if I can get anything near consistent. I will also contact 1066.