Mill a makarov bullet sizer to .365 or .366?

[sadams]

I have 2 makarovs and a FEG pa63, all chambered .365 (ish). After plugging the barrels I find that they are .365, .3655 and .363 respectively, all checked meticulously with a micrometer. My Lee Makarov bullet mold throws .365 - .366 LRN bullets. I cast my bullets with tire weight lead. I bought a .356 bullet sizer that a machinist friend is going to mill out for sizing these bullets. The question is should I have the sizer milled to .365 and split the difference, or should I Lee-ment my mold and have the sizer milled to .366? In the latter case, should I be concerned about the .003 difference in the FEG and the bullet diameter? I have read much of what is said on here about the optimum lead bullet diameter being .001 to .002 above barrel diameter to prevent leading, but you see my dilemma with the variance in barrel diameters. If necessary, another option is to optimize everything for the makarovs, milling the sizer to .366, and just not fire these bullets through the FEG. What would you do? Thanks

[BigDanS]

The Makarov 9x18 round is normally subsonic around 1000 FPS to 1100 FPS and maximizes around 23000 PSI . If you are using wheel weights and download a bit to 950 FPS you are going to have no issues with leading. The bullet diameter is listed at .365 and I would be comfortable with .366 in lead all day long.

I would not load them hot, and leave that for self defense and jacket bullets.

It does depend on your powder choices, but 3.2 gr of Titegroup and a 95 gr bullet make 18,500 PSI at 950 FPS, and that's darn near a perfect plinking round.

IMHO

D

[sadams]

So Big Dan, you wouldn't worry about a .366 bullet through a .363 barrel?

[runfiverun]

nope.
the extra 3 thou will raise your pressures less than 1-k.
go with the 900-950 fps like suggested above and you'll be fine.
the only thing you need to check on the smaller barreled gun is if the rounds will reliably chamber.
if it gives you some grief then I'd worry about a fix.

I'd even try no sizing the boolits from the mold before I milled the die out, then if the one gun needs them a tick smaller size just for it and segregate some brass for it.

[Duckdog]

It would be super easy to open up a Lee sizer. I don't think I ever sized anything for the 9mm Mak. I shoot them "as is" and have no issues... even in polygonal barrels.

[sadams]

Thanks folks

[leadman]

Check a fired case from the gun with the .363" bore and see if the inside diameter is large enough to release a .366" diameter boolit. If it is don't load to max. The cartridge overall length may have to be shorter also on this gun as the larger diameter may hit the rifling sooner.

[NuJudge]

My experience has been that if I size a really hard and a really soft bullet through the same sizer, the hard bullet comes out bigger. With my Lyman .366" die, it can mean .002". Add a little Tin and water drop the bullet, and it will come out of the sizer bigger. YMMV.