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View Full Version : Lee 44-200RNFP differences in size and weights from 2/ea 6 cavity moulds



Shuz
09-03-2018, 04:39 PM
Looks like Lyman has not "cornered the market" on having moulds with the same designation, but different designs.
Case in point is the above listed 44-200RNFP. It was by accident that i noticed quite a difference in weight between two 6 cavity moulds cast from the same exact alloy. I drop had 6/ea that weighed an average of 212g +- and the other mould drops boolits of an average of 207g +-. Interestingly the diameters on the heaviest vary between .429-.430 and the lighter boolits measure real close to .431 on all 6/ea. On closer inspection than the casual glance, I saw that 1 mould design has a deeper crimp groove than the other; and one mould has a rear driving band slightly longer than the other. OAL is only a mere .009 difference. Does all this make a difference? Prolly not, after all it is only about 2.5% difference in weight. But, until I can determine for sure that there is no real difference at the target, I'm keeping both separate.

By the way, this old guy has found a real nice light re-coiling and very accurate load with this boolit out of a 4-1/4" bbl'd Smith Mdl 69. 7g of Trail Boss and the 44-200RNFP unsized but just tumble lubed with LLA cut with mineral spirits. All 5 boolits land in a 4" bull at 25 yards with groups measuring between 2.17" and 2.41" with a velocity of 834 fps with an ES of 18 and Sd of 6. Primer is CCI 300 and cases R-P and OAL is 1.650". This was from a bench rest with open sights(Patridge front) and Smith X frame grips.

Grmps
09-03-2018, 05:46 PM
I'd call Peter at Lee and tell him about this and let him know these molds have a problem and that you need 2 identical molds so you can cast with 2 molds.

generally, 3% weight variance won't affect anything except long range shooting.