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9mm4545
01-15-2010, 12:21 AM
A question from a newby to the forum: is there any advice on what differences are encountered when changing from a cast bullet to a jacketed bullet of the same weight and shape? For instance, does the load data for a 115gr. FMJRN translate to a RNL 115gr bullet? I ask because I can't seem to find the exact bullet listed in the reloading manuals.

runfiverun
01-15-2010, 02:47 AM
yeah it usually does.
with the 9,and 40 i'd start low you usually end up there with cast.
with other cals [45 acp,44 mag] i make no distinction between j and lead,
till i get to rifle rounds. and even some of those i use j and cast loads as the same.

9mm4545
01-15-2010, 03:43 AM
Well, I gots me a bunch of shiny newly cast 115gr 9mm boolits. They mike at .3575" (more or less) (Lee tumble lube 124grRN from a 6-cavity mold using an alloy of about 16 BHT ) and now it's time to make them into something to shoot. Even though these are supposed to cast at 124 gr., for me they are coming out at only 115gr or so. Perhaps too much tin in the mix? I've been loading Berry clad 115gr. RN for my 9mm loads with 4.4grs. Bullseye and those shoot OK. I'll try the same load and see what happens. The next question: to size or not to size? Assuming the unsized bullits will chamber OK, is there any advantage to sizing to .356" for these cast lead boolits or should I just tumble lube them and load 'em up? Comments? Advice? Cautions?

runfiverun
01-15-2010, 04:22 AM
try the larger size first. see if it will fit your chamber in a case.
the tumble lube 9 mm boolit is one of the finickiest iv'e seen.
but when it works its great.
warm your boolits [hair dryer should do fine],add a little mineral spirits to your lla to thin it some and only add about 25% of the amount you think you need ,to start.
a light even coat should do.
then try a FEW.
make a dummy round to try first ,see if it'll chamber,see if it feeds from the mag.