Just cast 150 or so rcbs 40-350's from 20:1.

bottom pour.  (sorry, I like it).

I'm managing to get most everything in under + or - 1 grain.  (could be better if I put together the temperature controller PID thingy).

So I'm watching what varies - inspecting each as I move it (with gloves) from the towel to the cooling tray.

I look for:
a) base edge sharpness,
b) uniformity of smoothness/smear/tearing of sprue,
c) ease of dropping out of the mould,
d) sharp fill-out of the bands/grooves,
e) surface finish of the ogive (frost/shiny)
f) presence of flash.

I try to control these by adjusting distance between spigot and mould, time before opening and such.

Haven't weighed this batch yet.

I might.  But not for now.

I noticed last night, as an experiment, the progression of the edge of the bullet base and the nature of the cut of the sprue when I turned off the pot and kept casting.  Later today I'll weigh them to see what effect was made there.

As the temperature dropped the edge got SLIGHTLY less sharp and the sprue got less ragged to more smoothly cut.  It would be interesting to repeat it noting the temperatures.

I was never able to get my bottom pour to produce as many quality bullets as with a ladle.   

To me the key is constant temperature of the alloy plus a very consistent timing of each stage.  I count out each step.   

With my .32 cal Hoch mould I generally get long strings of bullets that show no weight variation on my Lyman DPS 1200 scale.  Keeping them within +/- 0.3 gr is pretty easy once the mould has warmed up and the rythm has been established.

Chris.

Hmmm.  Weighed the last 20.  (turned off the heat midway).  One could tell the drop in temperature as I cast the last 10. Graph doesn't reflect any trend in weight difference.  (Hmpf!)  But does show one that was carelessly cast, hence lighter.

I do my casting while standing up. That way I can do my fluxing, skimming, stirring, casting, sorting, whatever moving the things out of the way easier. I hate too much clutter because it makes me worry about fire or spilling lead. Anyhow, I can usually only get a hundred or so cast before my back gets stiff. No trouble with the arms or hands yet, at sixty-nine years. So, the most of my time is spent getting the pot melted and up to temp, since I heat a big pot. When I used to do this in my young years, I could cast three times this amount. But, I do like the large pot since it doesn't vary temp much while taking out a hundred or more slugs. Works for me.

calledflyer wrote on Jun 14^th, 2015 at 2:19pm:


Good observations.  I am only 68 so I've got some catching up to do.  I think what I've learned here relates to the temperature of the pot has an effect but less so than from my other timings and techniques (temperature of the mould).  Also controlling the rate of flow into the mould - controlled by both distance under the spigot and/or the adjustment of the rate (bottom pour) or the technique used in ladle pouring.   

BUT the fact that I could observe - in the process - slight variations - and adjust SOMETHING - was important.  Important to keeping consistency regardless of ladle or bottom pour technique!

Pentz wrote on Jun 14^th, 2015 at 10:35pm:

Am using the RCBS standard ladle (You need to Login or Register to view media files and links), but don't think there is any magic in it. Am sure the Lyman and others work just as well.

Another "stander" when casting, for all the reasons stated above. Have tried moving the loading bench stool to the casting bench (built a 2'x4' bench in the basement that is exhausted by a 150cfm bathroom fan to remove any 'outside' weather effects), but am standing after 3 or 4 bullets as it just works better to establish a good rhythm. The $50 spent on a PID controller, SSR & type K TC are a great investment for casting. Don't need to watch the temp as the pot level drops.

Cat Whisperer, i would be tempted to select 10 bullets in such a way that they span from the lightest to the heaviest cast in that session, and 10 bullets that you deem perfect and uniform and of the same weight. I would load them in 10 cartridges (or breach seat them, whatever)marked "bad bullets" and 10 cartridges for "good bullets", and would label carefully. A third group of 10 bullets i would use for fouling shots, after labeling. 
I would shoot 10 fouling shots and after installing 2 targets  of the same type, labeled for "bad" and "good" bullets, i would fire 1 bad bullet in the bad target, followed by one good bullet in the good target, and alternate this way, keeping each bullet group on it's designated target. 
I know that one would tend to think that the target shot with "good", sorted bullets will be better, but i have yet to see proof. 
Assuming that the cast bullets are not seriously mangled and defective, i expect that you will see no difference.
Shooters sort their bullets, use esoteric alloys blended on full moon, bullet lubes squeezed from manatee tear drops, and keep their pots at exactly 699.24 F because someone who won a competition did so. And if someone who won a competition comes up with a wacky bullet and caliber, everyone follows suit. 
Why not use a pragmatic, methodical, scientific method to try what works? 
By the way, i saw a 110 year old 32-40 rifle with the most evil looking bore you can imagine, never cleaned, that shoots fixed ammo with bullets cast hard out of a $60 mold, didn't even ask about powder and bullet lube...Well, the rifle hits golf balls at 200 yards regularly. None of the techniques, methods, or suggestions discussed on this board and elevated to fetish status are used to load for that rifle. What is different is the owner, who has an open mind and who tries what works in a methodical and analytical way. 
Maybe sorting bullets works for some shooters, it may be a waste of time for others.