RCBS Mould Whiskers

[harbor2]

Greetings to everyone. I have been lurking for awhile and what a wealth of information you all have here and I hope I can get some advice or how to's for my problem.
I recently bought my first RCBS mould, .45-230-CM I'm having trouble with it whiskering through the vent lines. My alloy is 30-1 and I pour with a dipper. I initally boiled the mould and looked for any burrs or crud. I cannot see daylight in the closed halves. I tried pouring with the spruce plate loose and not contacting the plate with the dipper's snout but the bullet's base will not fill out. Should I drive the alignment pins in deeper and if so how do you do that and how much?
From what bullets I have been able to use they shoot pretty good out of my S&W M22. Thank you in advance for any advice.

harbor2

[leadman]

Sounds like your dipper must hold alot of lead. The pressure from the lead in the dipper is forcing the lead into the vents.
Try lifting the dipper off the sprue plate shortly after the mold is filled. This will probably take a little experimenting to get the timing right. Let a little lead form a puddle on the top of the sprue plate.

[harbor2]

Thank you leadman for the reply. I have rested the ladle on the top of the mould and with a rocking motion poured the lead and leaving a large puddle but not touching the fill hole. I still get bad bases. I switched from a Lyman ladle to a RCBS ladle. THe Lyman has a bigger flow than the RCBS. I was able to get some usable bullets on the front cavity but not the rear one. And with the RCBS poured it traditionally against the spruce plate. I have several Lyman moulds and have never had this happen. I think my next experiment will be to try a harder alloy. Maybe I have too much tin in my mix. The bullets come out real shiny like a silver bullet.

[Calamity Jake]

The last 4-5 new RCBS molds that I have delt with have had vent lines that were to deep.
No amount of tweeking of anything fixed them.

Send it back, RCBS will replace it.

[harbor2]

Thank you for your reply Calamity, I'll send the mould back to RCBS. Have a good one.

harbor2

[Char-Gar]

95% of the time, bullet whiskers are caused by a speck or two of lead on the block faces causing the block not mate perfectly.

[HORNET]

If your pin height is correct, you could try heavily smoking both mold faces (after pre-heating) and then wiping across them with a gloved hand. The smoke can help partially block the vents. This assumes that you have verified correct alignment pin height. I know Lyman has good instructions on setting pin height.

[beagle]

You might try coating the mould faces with spray moly lube (several coats) while warm and keep it out of the cavities. This will accomplish the same thing of partially clogging the vent lines./beagle


If your pin height is correct, you could try heavily smoking both mold faces (after pre-heating) and then wiping across them with a gloved hand. The smoke can help partially block the vents. This assumes that you have verified correct alignment pin height. I know Lyman has good instructions on setting pin height.

[Marlin Junky]

A Rowell#1 may solve your problem.

MJ

[harbor2]

Thank you all for your help. I will check for pin heidth but I suspect the vents are too deep. I have several Lyman's and I have never experienced this before. MJ, what is a Rowell #1?

[Russel Nash]

It's a super duper special laddle that pours off the bottom. They come in various sizes. I can't remember the website right off but it is something like advancedcarmover.com .

[harbor2]

Thanks Russel I will do a search on the Rowell dipper.

harbor2

[shotman]

Leads too hot You said a 30/1 thats near pure need to keep temp down to around 500

[Bret4207]

The base is the important part. If the rest of the boolit is perfect I could live with scraping the whiskers off with my thumb nail. I'm betting the smoking/mould release will clog them up nicely though.

[Ben]

I'm with shotman.......I think your alloy is way to hot.

[Ol'Scudder]

In case you haven't found the source for Rowell ladles, the Antimony Man has them - and a good man to deal with. Size #1 should serve you nicely:

:http://www.theantimonyman.com/ladles.htm

[SciFiJim]

the bullet's base will not fill out.

I have this problem with cavity nearest the sprue plate hinge of a TL358158 mold. The solution that I found is to pour that cavity last and jiggle the mold gently while the sprue is still liquid. I think that it may not be venting enough under the sprue plate.

[harbor2]

I will try a lower temperature with the 30-1 and a harder alloy too. I use a little Coleman cook stove and I just keep it on high through out the session. I normally cast for my Sharps in 45-70, 400-500 gr bullets. So at a lower temp and try some harder alloy maybe it will do the trick. I appreciate the help from you all.

harbor2

[runfiverun]

usually if the base isn't filling out properly it's either venting under the sprue plate loosen or tighten it some.
or the plate isn't getting hot enough.
you might also need a larger sprue hole to help the fill out.

[Le Loup Solitaire]

Hi, Whiskers once upon a time were considered a sign of good pressure and a real good alloy like Lino or something close to it. Its the tin that does it. They were removed by rolling the bullets around on a towel or else by scraping with a fingernail etc. But who needs extra steps/work? If the bullet is well filled out then having whiskers isn't necessary, With a 30:1 ratio they shouldn't be there so the vent lines are as already pointed out are probably a little too deeply scored and the suggestions for plugging/clogging them are the good way to go. Old time molds didn't have vent lines and the bullets casted were good ones. There was even a practice of adding them if needed. Now about those bases... Bases don't fill out properly for one of a very few reasons (in random order) 1) contaminated metal-usually zinc. 2) metal not hot enough. 3) oil or some other hydrocarbon still in mold. 4) trapped air-improper venting.....this is is sneaky because it can be traced to two sources. A) the sprue plate is too tight....a sprue plate should swing freely on its own weight--It should sit flat on the blocks-not sloppy loose in that it can move up and down, but that when the mold is tilted 45-90 degrees it should slide freely. It might not be visible, but there is sufficient space for air to get by. A lot of folks have the idea that a tightly sitting sprue plate insures a sharp flat base (and that is important) and they crank the plate down to the point that it has to be moved back in place with some effort or resistance. Wrong! The second possible/probable contributing factor to the trapping of air under the plate is the notion that a whopping fat stream of molten alloy,slamming down from a bottom pour pot is needed to effectively fill the bullet cavity. Pressure is an important factor...that is true, but a stream that is slightly less than the diameter of the pouring hole in the sprue plate...you might find that it works quite well and it lets some of the air under the plate escape...especially in the base of the bullet area, as the cavity fills to the top. Ladles generally do not pour perfectly concentric steams of alloy so there is usually some room for air escape in addition to what is getting out under the sprue plate (and the vent lines). If it is a nozzle type and the nozzle is not stuffed tightly into the pouring hole (which it shouldn't be in order to allow the puddle to form for shrinkage) then some air if there is any, will also be able to escape. I think that it is important to try some of these variables so that the mold delivers the quality of castings that you are satisfied with. Enjoy casting and good shooting. LLS

[harbor2]

Well I tried most of the day to get some good bullets cast but didn't have much luck. I cleaned the mould again and tried loose spruce plate and a free pour from the spout, no whiskers but the base wouldn't fill out. Blackened the cavity with wood match contact pour the plate, whiskers and not quite filled out bases but better. Kept the heat down but didn't make any difference. I tried a harder alloy and no luck. I think I will send the mould back to RCBS and see what can be done. I appreciate all your time and the wealth of knowledge here. Thank you LLS for the very informative post. Have a great weekend.

harbor2

[Rick N Bama]

I had a new RCBS 9MM-147 that whiskered from day 1. I sent it back for a replacement & the new mold cast just fine with no whiskers at all.

Rick

[harbor2]

Thank you Rick. I'm sending the mould off tomorrow. Hopefully it won't take to long to get it replaced.

harbor2

[armyrat1970]

I have this problem with cavity nearest the sprue plate hinge of a TL358158 mold. The solution that I found is to pour that cavity last and jiggle the mold gently while the sprue is still liquid. I think that it may not be venting enough under the sprue plate.

Now that's something I never gave a thought to. Jiggle the mold a little before the sprue cools. Thanks SciFiJim. Gonna try it.