SSShooter wrote on Nov 23^rd, 2013 at 8:36am:

It does't cause a difference in weight because I don't wait to cast another bullet watching the scale. I keep as strict a cadence as i possible can when casting. putting a bullet on the scale and taking it off  and setting it on the towel in order cast is just one of the steps in my casting sequence. I use an electronic scale, and while a bullet is on the scale, I am filling the mold again, and while I am counting in my head on the timing after the puddle frosts, I glance at the weight, and either put the bullet back into the melt, or set it on the towel to cool. Most of my bullets weigh + or - about .2 grains if they are not at the same weight. The only time I normally have a large variation, is when I have some reason to stop casting...like burned my finger or something...LOL..and of course refilling the pot after 100 bullets....I'm talking about 535 grain bullets ...I do start out allowing a little lighter bullets , but, Not more than 1 grain Total!...This works for 1 1/2 MOA.

Terry....

Excellent chart. Have found I can weigh faster than I can inspect but reject those with obvious base flaws. Would have rejected several of those bullets. Rejects usually show some flaw, some don't. Does that chart question the value of keeping bullets in the order cast? Granted, it is a limited sample, but don’t see the gradual changes one would hope to gain by keeping bullets in order.

This is excellent work and the first semi-scientific approach to bullet casting I have seen. Please keep reporting your results.
Chuck

Chuckster wrote on Nov 23^rd, 2013 at 11:36am:


I've been dropping the bullet, refilling, placing the dropped bullet on the tray and waiting for the sprue puddle to frost over.  (I could add weighing and maybe make the time more consistent.)

I've thought of moving in a computer so I can watch the graph as I cast.  Then I could date-stamp each entry to watch variations in time too.  Heck, temperature monitoring could be added.

More soon.

Cast another batch.  40-350 RCBS mould this time.  Mould to sprue was better (less slop in clearance.  Mould felt tighter when closing.

Paid special attention to timing.  Pour, set mould down, move previous bullet to tray, drop bullet, refill.  Paid special attention to keeping each cycle the same as previous cycles.  Noted when heater of the Mag20 turned on and off (about a 50% duty cycle - each half being about 10 bullets [ouch]).

Found out that when I tried to TIME the process that a Tablet doesn't respond to touch with a gloved hand.  Bummer.

Cat_Whisperer wrote on Nov 23^rd, 2013 at 2:33pm:

Easy enough when your scale is 0.1gr readout. Have gone to a GemPro250 scale in past month and am pleased with both the considerable increase in speed of the readout and the 0.02gr accuracy. Hopefully, will be as reliable as the 7-yr old PACT scale it replaced proved to be.

SSS- do your 40cal 360s take down Rams well?Or do the 450s work a lot better.Are both creedmore type bullets.I am using 360 saecos that weigh 370gr and vary about 1gr.From the bench I can't see any difference in 200yd groups.I am pushing these at 1340fps.Any info would help.Bob,in PA.

I think the bullets are getting lighter as the mould heats up.

I'll try tomorrow a series with NO dropping the cut-off sprues into the pot.  It will make a good comparison.

Thanks!

I think that not pausing every 8th or 10th bullet for a sip of beer helps too.