RCBS 38-148-WC Weights and Loads

[Thomas Traddles]

I casted 100 boolits from an RCBS 38-148-WC mould with 1-16 alloy and the weights of the boolits fall between 152 and 153 grains. Interestingly enough, the bullets from RCBS my 38-158-CM mould weighed between 157.5 and 158.5 grains and were cast from the same alloy. I am puzzled by the difference in weights and if someone could clue me in as to why the 148 WC casts so heavily, I'd be grateful. More importantly, I am wondering about charges. Can I follow the Lyman loading data for the 148 grain or will the initial charges prove too light as a starting point for working up loads for the heavier bullet? If not, should I look to develop loads from data on bullets weighing 155 grains? Thanks for the help.

T

[Wally]

All my .38 Caliber WC molds cast 5 grains+ heavier than nominal. No big deal, I use the loading data for a 148 grain and have no problems in doing so. The reason they cast heavier is because the alloy I am using has more lead than the alloy the manufacturer used.

[Le Loup Solitaire]

I use a 148 grain wadcutter cast from straight wheel weight metal. It is a double ended flat face wc and usually casts at 149 to 150 grains. I seat it flush with the case mouth so it can be used in my S&W 52. No crimping involved. There are several powders that can work well. The classic load is 2.7 grains of Bullseye. I prefer to use 2.6 grains of 700X and it shoots very accurately as a target load for 25 yards...the recoil is less sharp (to me) with the 700X. The same loading also works well in my revolvers. An overage of 5 grains is not a lot; a slight difference in alloy can do that. You can start with lighter charges for the wc bullet and work up from there for the heavier 158 grainers, just don't go over maximum recommendations. Keep a close eye on your grouping as you work up. as with any other caliber. LLS

[Thomas Traddles]

Thank you.