1 side pretty 1 side UGLY

[charger 1]

Hey just lookin for opinions as to what would cause iron 405 45 cal RCBS to cast nice sharp edges on one side and the other not filling nicely or frosting severally. The stream is not perfectly straight outta my pot,could that be enough?


If somebody knows how to move this please move it up one catagory. Sorry folks was sleepin

[freedom475]

I had that same problem with a new RCBS I have. This is what I did to fix it.

Wipe mould faces and cavs down real well with acetone. Clean the vent lines out with a knife, then wipe again with acetone and a Q-tip.

Now just go to casting WITHOUT applying "drop-out or smoking cavs with lighter/match.

To keep from galling I do spray the bottom of the spure cutter and the top of the mould with "drop-out" with a boolit in the cavs to keep the "drop-out out of the cavs. ( because I don't have any Bullshop lube) This worked well for me. Hope it helps.

[KYCaster]

Is the ugly side always where the cavities are closest together? If so its poor venting that can be agrivated by too high a temp.

Like Freedom said, clean well, scribe the vent lines and hone a bevel on the top of the blocks. Loosening the sprue plate can also help, but that can lead to other problems.

Jerry

[sundog]

If you continue to have the problem after doing what has already been suggested, try this.

First, Drop-out is not all that bad a product, but do NOT spray it directly into the cavities. Spray some on a q-tip and mop the cavities, swirling the tip along the grooves it cleans as well as leaves a light deposit of graphite. Do not use too much. Cavities have got to be clean before you start. Sometimes this will do wonders. It will make boolits drop easier provided there are no other problems.

Next, RCBS notoriously makes the sprue plate holes too small. If you decide your melt is not going in properly open the holes one drill bit size at a time and hand ream the holes. The hole is not only the way for the melt to get in, it is also an additional vent. Then, and don't skip this step, hone flat the under side of the sprue plate making sure there are no burrs around the holes. Use a fine stone or crocus/emory paper on a flat surface. With holes opened up, sometimes melt temp can be reduced because you will have a better flow. This helps regulate the block temp also.

Large cavity blocks tend to frost boolits very readily when you get going good. You may need a to slow down a little or use a damp rag to set the mould on every throw for just a second. Experiment a little and see what that mould likes best. Each mould cast differently.

When all else fails clean the mould with brake cleaner and a bronze 'tooth' brush, even in the cavities.

How many times has this mould been used? Is it new? New moulds sometimes require a session or two before they come into their own.

[charger 1]

Thankyou all. Have done some of yer ideas but not cleaning the ventillation. Will get at that today. That makes sense cause once upon ago it casted fine..Thanks all