Graybeard Outdoors banner
1 - 6 of 6 Posts

·
Premium Member
Joined
·
475 Posts
Discussion Starter · #1 ·
What could cause cast bullets to be out of round? A "friend" gave me some 170gr PBSWC to try in my .357 Max. I need to size and lube, but I find that they are grossly out of round, the worst being .352" in one direction going to .360" a quarter turn around. Sizing brings down the larger diameter, but of course does nothing for the undersize measurement. He uses Lyman molds, so kinda doubt the problem is there. I'm kinda thinking about just melting them down and recasting in my mold, at least I know mine makes round bullets. Goatwhiskers
 

·
Premium Member
Joined
·
1,104 Posts
the melt temp of the lead may have been to low i would bring temp up to 700 degree
worm the mold up to i use a hot plate for this and yes you can get a Bad mold from Lyman
 

·
Moderator
Joined
·
24,155 Posts
most of the time its caused by a mold not completely closing. I fought one 500 linebaugh i bought used for accuracy. It wouldnt shoot anything for crap. Surely not typical of johns guns. I sent it back to him twice and both times he checked it out and said there was nothing wrong with it. The only reason i didnt call him out on it is i know hes a completely honest guy. Well about the same time my buddy was working up loads for his new 50 ak and i gave him pile of bullets. It too wouldnt shoot and he sent it to ben forkin to check out along with some sample rounds and some of my cast bullets. Low and behold ben called and said my bullets were way out of round. I got thinking and remembered that i had just bought a new star 512 die because i lost the one i had in a fire. Got checking and that die was out of round and was causing the accuracy problems in both guns. It will effect accuracy! One other thing that can happen when casting is with a two cav mold the metal in the region between the two cavitys is the thinest spot of the mold and can get hotter then the rest of the mold and these hot spots can effect mold fillout. Most of the time it will show itself as a frosted look on the sides of the bullets where that area is. this will usually not happen with molds like 357s its more apt to happen with something like a 475 or 500 that have bigger holes that dont leave much metal between the cavitys. Some of my 50 cal two cav molds about have to be casted as a single cav.
 

·
Registered
Joined
·
253 Posts
Hello, Goatwhiskers. You state in your post that these are Lyman moulds..and so doubt the problem is there...But that is precisely where the problem is! I have been fighting with Lyman moulds for years..sometimes you find a winner..but oftimes they are a bit out of round..although .008" is a bit unusual.
I think the problem comes from their method of cutting..the blocks are clamped in jig, and then fed simultaneously
into the revolving "cherry" cutter. There might be dirt of tiny chips that hold one block out further than the other, hence, that block gets cut a bit deeper.
The owner might take a look at the alignment pins..one might be too far out, holding blocks apart.
 

·
Registered
Joined
·
1,185 Posts
You might want to go ahead and size and lube a few of those bullets. They will be as round as your barrel, by the time they have traveled their own length, so the biggest problem you might have is leading. You likely won't get match winning type accuracy, but they may just shoot well enough for most applications.
 

·
Premium Member
Joined
·
475 Posts
Discussion Starter · #6 ·
Guess I will try a few of these. Using a Lee sizer, it reduced the major diameter but they were still .003-.004" out of round. Messing around, discovered that if I push the bullet thru the sizer backwards the driving band gets squeezed around such that it is only .001" out and that only in one spot. Hardly touches the rest of the bullet. Probably be OK for practice work. Goatwhiskers
 
1 - 6 of 6 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top