Stop the Presses!...my new LEE

[PatMarlin]

C309-180-R is casting at .311.. :shock:

I can't believe it. A Lee mold casting OVER diameter with WW's? How can this be?

Oh well- the shank is still under. Even for a Gator check. Now that's the Lee I love and know.. :mrgreen:

Does cast like a dream though, and loves Bull Plate Lube. I like aluminum molds.

-by the way is this boolit considered to be a bore rider?

[grumpy one]

I just got a 309-170-F yesterday, and it's certainly going to end up being a bore rider, because the first thing I did was lap it to size for my 30-30 microgroove (bore is a remarkable .306"; groove is .3116" at the breech and .3112" at the muzzle - at least it tapers the right way). I was less lucky than you with my mould - as received the as-cast diameter was .309" at right angles to the parting line, and .312" parallel to the parting line. I've lapped the driving bands so the rearmost one is .3122" at right angles to the parting line as cast and the others step down to just under .312", so I should be able to size to .312". Incidentally as received the driving bands tapered the other way - the rearmost band was smallest, which didn't suit me at all. I can't size the bore riding section, and it is .002" oval, so I just lapped it to .304" - .306". If there is a way to reduce the ovality of Lee moulds while lapping I didn't find it. I seem to be able to reduce ovality a little with steel moulds, but so far I haven't found the formula for doing it with aluminium ones. Cast a couple of hundred bullets with the mould today - it's easy to use, as you say, but the results are rather un-beautiful compared with the Lyman moulds I'm used to. Nasty lathe marks, and strangely-shaped undersized grease grooves.

If you just measure the diameter of the nose, and it's about .300" or so (mine was .301 - .303") I'd call it a bore rider because the parallel part of the nose is the same length as the total length across all of the driving bands. To me that would be the minimum nose proportion to qualify as a bore rider. Having that amount of nose overhang and not having it aligned by the bore would give some pretty poor results, I think. I haven't seen anyone else's definition of bore rider - maybe one of the experts will offer one now.

Geoff

[Bass Ackward]

Geoff,

Pretty simple definition really. A bore rider is a semi wadcutter design bullet for a rifle where the nose portion is larger enough that it is in contact with the lands. If your bullet does NOT make contact on the nose, then it is simply a semiwadcutter for a rifle where the front band performs a scraping function and all that weight is unsupported.

I have designed bore rides for my handgun and levers mainly for centering in the bore and find this type of semiwadcutter to have advantages over traditional Keiths in accuracy when the ride portion is long enough to make contact with the rifling before the sharp shoulder contacts the cone and dents.

[grumpy one]

Thanks Bass,

I was thinking about my "plinking" bullet, 311255 (115 grain PB RN) which has almost no nose at all, but what it has is about bore diameter. I wouldn't call it a bore rider because the few thousandths of an inch of bore diameter nose, right back against the front of the crimping groove, isn't capable of supporting or guiding the bullet to any worthwhile extent. Obviously better to have it than not have it, but I wouldn't expect great things from it due both to lack of leverage and negligible bearing area.

Speaking of what happens when the front of the driving bands hit the back of the rifling, I've been finding that the throat of my milsurp FN K98 30-06 always has lead in it. It has a .2986 bore with a groove diameter of .3096 at the breech and .3102 at the muzzle - after a long throat of about .311 (who knows, through all the lead) the very deep rifling starts fairly abruptly, and I seat the nose against the back of the rifling because I can't engrave it. The reason I can't engrave the rifling is that my bullets are 30 BHN (air cooled foundry type), with a nose diameter of .300, and there is no way I can force the hard nose into the .2986 bore - I just push the bullet deeper into the case. I've found that if I size the driving bands to .310, I get a slow build-up of lead and lose accuracy. If I size to .311, it blows the lead out like snot and starts to shoot well, but there is still always lead in the throat, and the ultra-hard foundry type really irons onto the steel and doesn't come off with either bronze brushes (which only last a couple of hundred strokes in my tight bore) or strips of copper wound around an old brush. I can get it out slowly with Keenbore Lead Removal patches, but it seems to come right back the next time I shoot the rifle. Whenever I slug the throat I find diameter varying between .310 and .311. I don't know how much of the problem is due to the foundry type being so difficult to remove mechanically, and how much is due to the beginning of the tight bore shaving the driving bands.

Geoff