Lee 2 cavity more consisten than 6 cavity

[DEVERS454]

Well, after a quick casting session, I decided to weigh my bullets to see just how consistent they were coming out.

Of the ones that pass visual inspection, the 2 cavity mold appears to drop much "tighter" groups as far as weight.

Straight wheel weights drop right at 286.5gr (+/- .5gr) from the Lee C452-300-RF 2 cavity mold.

From the 6 cavity, its all over the map. As high as 287 and as low as 280.

When I switched to 92-6-2 alloy, which I have ALOT of, I am getting from 274 to 284 for the 6 cavity, but, again, with the 2 cavity, it stays right at 282 (+/- .5gr)



Does this seem "normal" for other folks?

[grumpy one]

Have you segregated the bullets by cavity, to check whether you have variations in cavity dimensions that are at the root of this? Superficially there are three possible causes: different cavity dimensions, different bullet solidification characteristics caused by heat flow conditions in the various parts of the mould, and uneven mould closure from cast to cast. The first and last can be fixed, the middle one probably can't. However if the second cause applies, most likely everyone else will be having the same experience you did.

Geoff

[Buckshot]

..............Wow, that's a bunch! Actually the main thing is, are they round? Are they well filled out? If so, look at it this way. Your 6 cavity is giving you 6 different boolits! You have a lot of choices, ha! Of course, the downside is that you DO have to weigh'em to find'em.

.................Buckshot

[David R]

I just bought an RCBS Rangemaster 750 digital scale. I have been wanting to weigh some boolits for a 300 yard match.

My 308 shoots the 311644 into about 5" at 300 yards. If I could get 3", I have a shot at winning the match or at least having to break the tie with an X count. SO I wieghed a bunch of those boolits and seperated them. They varied by 3 grains total. I had a few that were over and a few that were under (fliers for sure). These are out of a Lyman 2 banger.

Then I weighed a bunch from my group buy 311407 six banger. After about 100 or so, I threw em all back and decided they didin't need to be weighed. Most were 172.something. Almost all were within one grain.

David

[45 2.1]

That group buy 311407 is a really good mold. I wish I had bought two of them. I've got extremely good accuracy with it. It is especially good in the 308 semi auto rifles. I size to 0.311" and lube the grooves on the 0.311" portion only.

[caneman]

My big problem with the 6 cavity moulds is arthritic hands. I do fairly well with 2 cavity but the hands go to pot quickly with 4-6 cavity big bores. Never tried any 6 cavity in 30 caliber but I expect that would be pushing it.

[Maven]

If you can manage segregating enough of the droppings from all 6 cavities without too much heat loss between pours, you may be able to identify the offending ones. Assuming you're able to control 2 of the 3 factors mentioned earlier, the answer may be to fill only the cavities that show the least variation in weight. (This is easier if you use a ladle.) Also, if you use a Lyman or RCBS ladle, try filling only 3 cavites at a time, re-dipping and then filling the remaining 3, which may give more consistent results.

[PatMarlin]

I'd also be interested in seeing what happens if you only used the 4 center holes?

After all the ends... #1 and #6 are slighty surrounded by different sized metal, as was pointed out to me by Bullshop Dan that this becomes more of an issue with larger boolit molds.

So I'm thinkng casting the center 4 only, may make a difference. Kinda defeats the purpose of a 6 hole mold, but if the 2 on the outsides are what's causing the problem, then that would solve it... :drinks:

[Four Fingers of Death]

There are going to be a lot more variables with a six cavity mould I suppose. For cutting edge target work, you probably would be better off with a double or single cavity, just stands to reason. I've only got one 6 cav mould, a 32/20 GB from Willbird, for which I don't have a rifle at the moment so I'm not realy able to comment. Mick