Sizing issue with MP 359-125

[novalty]

In my last batch with this mold, I've noticed while sizing to .358 in my RCBS LAMII, that the bullet is sizing up above the front driving band into the shoulder. The bullets were cast with almost Straight COWWS, at roughly 700* in my ProMelt. The mold is clean, and I thought maybe the mold wasn't closing enough, but I'm not getting any flashing. The bullets drop in solid form around 133grs. I've tried raising the stop on my LAMII to stop it at the front driving band but it the sizing die doesn't lube the groove at that height. Appreciate any suggestions.
Here is the bullet unsized:
http://i100.photobucket.com/albums/m11/novalty1970/Reloading/Casting/359125%20Unsized_zpstnexdnhb.jpg (http://s100.photobucket.com/user/novalty1970/media/Reloading/Casting/359125%20Unsized_zpstnexdnhb.jpg.html)
Here are some sized to .358 sized beyond driving band:
http://i100.photobucket.com/albums/m11/novalty1970/Reloading/Casting/359125%20Sized%20to%20358_zpsocle2fsz.jpg (http://s100.photobucket.com/user/novalty1970/media/Reloading/Casting/359125%20Sized%20to%20358_zpsocle2fsz.jpg.html)
Here is one sized to .358 that didn't size beyond driving band:
http://i100.photobucket.com/albums/m11/novalty1970/Reloading/Casting/359125%20Sized%20to%20358%20Front%20Driving%20Band _zpsiifgqiov.jpg (http://s100.photobucket.com/user/novalty1970/media/Reloading/Casting/359125%20Sized%20to%20358%20Front%20Driving%20Band _zpsiifgqiov.jpg.html)
Here is one sized to .357 with even more pronounced sizing beyond front driving band:
http://i100.photobucket.com/albums/m11/novalty1970/Reloading/Casting/359125%20Sized%20to%20357_zps0kyqlcsf.jpg (http://s100.photobucket.com/user/novalty1970/media/Reloading/Casting/359125%20Sized%20to%20357_zps0kyqlcsf.jpg.html)

[rollmyown]

A photo will help.

[Bohica793]

The very first thing I notice is the seam in the unsized bullet in the first picture. This tells me that the mold is not closing correctly. Also, have you taken a micrometer and measured your unsized round, both for size and roundness?

[BenW]

Out of round. That wave look at where the driving band ends is from the an oval being squeezed to a circle.

[novalty]

I measured a couple un-sized and out-of-round appears to be the issue. Only thing I can determine is that I must not have the mold as clean as it should be. There is some lead hazing that I didn't think was significant, but only thing I can see that could cause issue. Should I toss the batch back in the melt, or are they okay for plinking?
http://i100.photobucket.com/albums/m11/novalty1970/Reloading/Casting/IMG_1290_zpsvzosv2ks.jpg (http://s100.photobucket.com/user/novalty1970/media/Reloading/Casting/IMG_1290_zpsvzosv2ks.jpg.html)

[BenW]

As long as the minimum diameter is what you want (or if the boolit is sized all the way around) it's fine for plinking.

Really hot aluminum molds will distort when too hot (not your issue I don't think), there is grime or lead between thr mold faces, or the alignment pins are not actuallt alogning the mold (possibly worn out or have been pushed back into the blocks if they are just pressed in). My vote is grime or some flash or a burr

[novalty]

I'm guessing the ones that are sizing correctly might have been towards the beginning of my casting session, and the ones that are out-of-round were towards the end--and I cast about 700 of them. Measuring them unsized I got .359" and as high as .362". The lead that shows on the mold isn't very built up, but I'm going to put it on the hot plate to warm up, and then see if I can get it cleaned off. Will probably use the bullets that don't look too wavy for plinking, and toss the rest back in the pile to melt down. Appreciate the help.

[dondiego]

Unless you are competing, or there are obvious defects, shoot them all.

[BenW]

If they're getting out of round near the end of the session, I suspect your mold is too hot. It sounds like your temp is perfect in the beggining of the session, but you may want to slow down or lower the temp a tiny bit later in the session.

[tomme boy]

I had one of these moulds and the pins were too large. Would not let the mould close. I PM'ed MiHec the size of the pins and he said they were too big. He sent new ones right out.

[Maximumbob54]

Mine look exactly the same as cast. Worse, I get fins around the HP. I have to put the death grip on the handles lose the fins. And then they don't want to drop from the mold. I thought it might be the depth of the lube grooves that hold them. That mold is by far the most finicky MP mold I have in the collection. But now post #10 makes me wonder if the pins are just a hair too large.

[novalty]

Thanks for the suggestion Tomme Boy. I didn't think there was nearly enough build up to result in the out of round, but it still could be the case. I'll check my pins as well.

[wonderwolf]

I just got my 359125 and cast with it yesterday, have not size/lubed them yet but I just measured them before I found this thread and mine vary between .358-.362. The seem on mine is hard to find and I'm always careful to make sure the mold is closed correctly each time. Could it be the bullets are not cooling enough before activating the pins? A few got stuck and didn't want to move out of the cavity half to be ejected, those were recycled though.

[BenW]

That sounds more like a warped block or worn cavities. Casting hotter on my lee molds makes them more out of round even with no seams where the blocks meet.

Try casting cool, warm, and hot and check out-of round for each batch. That'll tell you if your molds prefer a temp or if there is an actual mold problem.

[wonderwolf]

Sized about 150 this morning @ .357 hardly touched them, they look great. Not sure where the runout was but they look uniform and the bearing surface hardly touched. Can't wait to get on the range with these. I'm thinking 4.0gr red dot