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TGM
10-05-2008, 03:30 PM
What may I be doing wrong that I get out of round boolits from a Lyman 378674 mold. I am useing mostly WW with a small amount of reject boolits that were cast with a #2 mix. I am hand dipping at a temp of approx 775 degrees. Any suggestions that might help would be appreciated. The boolits weigh 335 gr.+/_ 1gr.

TGM

44man
10-05-2008, 04:07 PM
That is common with cherry cut molds. The cutter leads at the parting lines. .001" or so will not hurt anything. How do they shoot?

mooman76
10-05-2008, 04:41 PM
That is very common with Lee bullets moulds. They will go back to round when you size them. Either in the sizing die or down the barrel, doesn't really matter that much!

Doc Highwall
10-05-2008, 05:38 PM
What size are they coming out of the mould. If they are slightly small you could lap the mould and make them rounder and slightly larger at the same time. Kind of like a win win on both problems. Ultimately what matters is how well the shoot.

TGM
10-05-2008, 07:08 PM
It is a Lyman mold. They are coming out of the mold .378 on thehigh side and.374 on the lowside. Sizing does not round them out and they come out of the sizer .377 high and .374 low. I have not tried to shoot any due to there being out of round.

TGM

Doc Highwall
10-05-2008, 07:36 PM
TGM, you have to slug your barrel, and as long as the boolits are larger then the slugged dimension you should not have a problem. Your out of round problem could also be that the two mould halves are loose to one another. If you purchased the mould used it could be that the person that used it was closing it too fast and peen-ed the holes where the two halves come together. This can be corrected by seating the alignment pins deeper, just enough to take the play out. Always close the mould slow and use some kind of lube on the alignment pins and sprue cutter screw.

TAWILDCATT
10-05-2008, 07:44 PM
what is your bore size?make sure there is no lead on face of mold.I believe the molds should be filled either by a bottom pour pot or a ladle like lymans.turn mold on side and connect the ladle,turn mold face up and turn ladle up.I never use the ladle except on some of my pre war molds.[they have small faces].try the bullet with out sizing.the bottom pour can be used to touch the mold and get pressure on lead or dropped in to mold.:coffee:[smilie=s:

MT Gianni
10-05-2008, 08:25 PM
If the large size is across the part lines Beagle it.

dardascastbullets
10-05-2008, 09:18 PM
It is a Lyman mold. They are coming out of the mold .378 on thehigh side and.374 on the lowside. Sizing does not round them out and they come out of the sizer .377 high and .374 low. I have not tried to shoot any due to there being out of round.

TGM

This is a very interesting problem. I must ask .... is this a new mould? If so, then I would recommend that you contact the seller and ask for your precious money back. A mould that is casting a bullet that far out-of-round is scrap - totally unacceptable.
Now, if it is a used mould, I would then suspect that you have mismatched halves. The halves come from two entirely different moulds. Which could be caused by the alignment pins not set properly, or, each half was cut with a different cherry. By chance, are there hand-stamped numbers or letters on the halves to indicate a matched set and/or a used set (which would have been applied after they left the Lyman facility)?

Heavy lead
10-05-2008, 09:44 PM
I had a very similiar experience lately with a brand new Lyman 452424. I casted about 200 before I realized the problem. The alignment holes (opposite side of alignment pins) were egg shaped, there fore the halves weren't lined up right. The boolits looked good, so did the mould, until I went to size. Varied from 457 to 449. I sent it back, darn thing was brand new. Don't know if this is what's causing your problem, but you might want to check.

runfiverun
10-05-2008, 10:10 PM
bet they got some new equipment and haven't figured it out yet.

Heavy lead
10-05-2008, 10:18 PM
Could be, I replace it with a 454190, that casts beautiful boolits, and pins were lined up right. So I don't know. Myself I prefer RCBS moulds, seem like they need less fiddling with to make a good boolit. But I've gotten 3 Lyman 4 cavities lately and they all worked out real well.

Will
10-06-2008, 11:02 AM
I had the same problem with a 311410 cast .312 x .306 and shot 10" groups from a .308 tube. I emailed Lyman and they had me send it to them. A week later they sent a new one that was near perfect. They only give a 1 year warranty and mine was well out by the time I found the problem but they replaced it anyway, no questions asked.

leftiye
10-06-2008, 02:13 PM
Yer mold halves aren't aligned properly. See if there are burrs on the alignment holes, and/or pins. Not uncommon for Lyman to bugger up a mold in this manner during production. You may be able to straighten the mold halves out some by tapping one half in the correct direction with a hammer while the other half is held in a vice. This may also just open up your alignment holes so that the halves move around in relation to each other (not good!), so be muy gentle with this. oOtherwise, the lapping idea might help, though it tends to create oval cavities anyway.

I believe Lyman's spec on alignment (out of round) is to be within .001" of round. You could therefore send your mold blocks back to lyman for replacement if you decided to.

mike in co
10-06-2008, 05:01 PM
if you are out of "round boolits", shoot the next best ones......lol

mike in co

TGM
10-06-2008, 09:16 PM
I removed the mold from the handles and found that the halves did not alaign properly, they could be moved back and forth. I punched the alaignment pins out for more engagement and now there is no movement between the halves. Now I need to get a larger as cast diameter so when I size them they should be OK, at least good enough to try shooting them. Thank all of you for your input to solve my problem.

TGM

MT Gianni
10-06-2008, 10:31 PM
Hope that fixes things. Wherebouts are you in MT? Gianni in the SW part of the State.

TGM
10-07-2008, 01:46 PM
I live in the big city, thats Billings.