"Is the rcbs model 505 good? i have one in mint shape,..."
There are no better powder scales than the 505 and it's brother the 1010 available. Acually, RCBS' beam scales are made by the Ohaus company and they are perhaps the top scale maker in the country. That's not to say the other makers are any less quality but Ohaus has long been the standard of comparison.
Those who buy digital dumpsters, or just digital scales, and happen to get a good one love 'em...until they crap out. Those who get one that craps out early have different opinions. And what you actually get depends on pure luck, not brand. Those things are much too costly for me to trust in luck to get a good one. Last I heard the warrantee is only one or two years. I'll keep using my absolutely reliable 45 year old Ohaus scale and Redding powder measure...and I'm a retired electronic instruments tech!
Question: Are you a "U.S. Marine"? If so, thanks. I ask because I have a near new Marine grandson-in-law in Afgansitan now.