Casting/powder coating/ loading questions

[SpeedyR]

enjoying the info posted. I've got lead and molds to try out in the near future. I also picked up a junk convection toaster oven and some PC from smoke on cast boolits. I'll have to check on my molds and see if they are GC or not. The main molds I have are a 300gr 44mag/special Lee, a custom group buy 6.8spc Lee mold (I think around 110gr?) and a custom NOE mold for 300BO around 247gr. I've never casted before so once we get thru the current situation I'll be asking for some pointers.

I've got a partially filled 5 gallon bucket of COWW in the garage, might try to clean them up and cast into ingots/muffin tins in the next few days. Already sorted out the non lead stuff, but smelting them is gonna be dirty and not sure I want to spare one of my limited supply of N95 masks for the task.

 

[Freshly Minted Georgian!]

If the base of your cast bullets is square and flat you shouldn't need them. Anything short of perfectly flat and perfectly square is gonna cause you a problem and you should consider a gas check. Adding a check will provide you a flat, concentric and square base to your boolit. Some claim that it also acts in essence as a "wiper" to help scrub the bore of lead fouling from the bullet itself although I've never noticed an appreciable effect there. Leading obviously gets worse the faster you push a boolit. My general rule of thumb is to try wherever possible to use a gas check for any rifle calibers, including hotter pistol rounds being fired from rifles.

 

[pistolpat]

If the base of your cast bullets is square and flat you shouldn't need them. Anything short of perfectly flat and perfectly square is gonna cause you a problem and you should consider a gas check. Adding a check will provide you a flat, concentric and square base to your boolit. Some claim that it also acts in essence as a "wiper" to help scrub the bore of lead fouling from the bullet itself although I've never noticed an appreciable effect there. Leading obviously gets worse the faster you push a boolit. My general rule of thumb is to try wherever possible to use a gas check for any rifle calibers, including hotter pistol rounds being fired from rifles.

Subsonic loads shouldn’t cause any leading problems right?

 

[biker_bill]

Subsonic loads shouldn’t cause any leading problems right?

Right and many of us have proven that.
Keep them slow!

 

[rosewood]

So the gas check is just to aid in accuracy?

It depends. Something you have to try in an individual gun. In my higher velocity/magnum type loads, I almost always use gas checks and the shoot as good and sometimes better than jacketed bullets.

Molds are made specific for gas check or not. They have a rebated base for the gas check to slip over. I suppose if you are making your own gas checks, you could make them to fit a base without the rebated rim, I have no experience with that.

As for leading, it is generally caused by hot gases slipping around the bottom of the boolit, melting the lead and pushing it around the boolit as it travels along the bore. Too soft lead going to fast can also shear off lead in the rifling. The gas check helps to seal the bore and keep the hot gas directly off the edges of the boolit. The gas check also grabs the rifling to impart the spin on the boolit even if the lead is a bit soft. I have a Lee 130 7mm gas checked boolit that I push well over 2000 FPS in the 7mm-08 with no leading issues. I have had leading with a 200 grain RNFP in a 45 ACP doing only about 800 FPS. Boolit fit in the throat and barrel has a big effect on leading also. If it is loose, you get a lot more leading, tight fit, seals gases and reduces leading. Powder coat in my experience has stopped leading where I have had issues. Using the Lee 175 grain .401 mold, I powder coat those boolits and they shoot better than any jacketed boolit in several of my 40 S&Ws.

Gas checks can cost anywhere from 2 cent to 4 cent each, so that can make your total cost go up also, something else to consider.

Rosewood

 

[Frankmako]

Yes and no. Also the gas check will let you run the bullet faster.