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Wm Cook
12-11-2017, 06:37 PM
If someone could take a shot at explaining to me what I'm doing wrong I'd appreciate it.

The boolits are 22 cal. The little ones on the left are dropped out of an aluminum NOE mold. They literally fall out of the mold and they all look spectacular. Temperature was run about 370 and I was pouring and removing them from the mold as fast as I could move. The bullets on the right are from a Lyman 225438 and should come out at about 44 grains. Both were cast from the same alloy, same day. The pot is an old Lyman XX bottom pour.

The NOE are fine but the Lyman's looks are ugly as sin.

I scrubber the Lyman mold multiple times. I tried acetone, soap/water, boiling water and Comet paste etc.. I tried temperatures running from 290 to 380. I tried casting fast and casting slow. The mold is 10+ years old but its seen little use. Since I ruled out temperature and alloy as variables I guess I'll have to go back to scrubbing the mold once more. Maybe over the years it picked up some kind of film that's messing up the finish on the bullet.

Is it possible to polish the cavity with anything harsher than Comet paste?

209340

Pipefitter
12-11-2017, 06:45 PM
Have you tried shooting any of them yet? You might be surprised. I see no wrinkles or frosting, maybe a touch more tin would help.

gwpercle
12-11-2017, 06:59 PM
If you have cleaned the cavities with acetone then the cavity isn't contaminated, might be a venting problem. The NOE's look well filled out so it must not be an alloy problem.
After cleaning the cavities with Comet you might need to re-season the cavities by just casting a bunch of boolits . Iron/steel moulds need to be re-seasoned like a cast iron cooking pan .
Are the sprue holes large enough...sort of looks like not enough flow or a venting problem....is the Lyman blocks scored or smooth unvented ? Pictures ?

If these are the best it will do then do like Pipefitter suggest...size , lube and shoot ....results may surprise.
Gary

OS OK
12-11-2017, 07:57 PM
The Lyman's look like they reflect the interior of the cavity, you have good fill-out. If you want smooth and shiny you might try polishing with some rubbing compound for car finishes...it doesn't cut awful fast but it will smooth things a bit.
If I changed things at all, I'd run the pot up to 385*C., that mould has a lot of steel to heat compared to the size of the casts.

Those look fine to shoot to me though.

243winxb
12-11-2017, 08:18 PM
Iron lead molds are more porous then aluminum. The Lymans looks ok. Shoot them.

Bzcraig
12-11-2017, 11:48 PM
I would just shoot them. Though not as prudy as the NOE boolits, they look plenty good enough to shoot. If you're bent on making them smoother, search using 'beagling.' I don't believe you're doing anything wrong.

runfiverun
12-12-2017, 12:13 AM
you still have something in the lyman mold.

beagling won't help the situation.
scrubbing might but I bet a little lap polishing would get those high spots broke down.

check your mold out through some high magnification, or run a pointy stick around in the cavity's and see if you can feel any roughness.

country gent
12-12-2017, 12:23 AM
A light lapping with tooth paste may help some. clean vent lines with a scribe or awl ice pick. As a last ditch stone a small bevel on top edge of blocks under the sprue plate. this makes a final vent line right at the top.
Theres a lot of "block" there and little lead going in. your sprues are probably as heavy or heavier than the bullets, so heating the blocks up and keeping hit may be part of the problem. You might try a little hotter lead as mentioned above. Also preheating blocks on a hot plate to 350* - 400* before casting may help.
I would size lube and shoot some as is first and see how they do. Test them first and then try to "improve" them after you know how they perform.

Wm Cook
12-12-2017, 12:34 AM
As far as accuracy, I shot eight 5 shot groups today with the 44 grain Lyman’ s and although a couple groups showed promise there would have been none under 1 ½” @ 50 yards. Today I was using Unique 2.5 - 3 grain (1,214 - 1,434 fps), half with small pistol and half with small rifle. Neither primer showed an advantage. Velocity was fractionally slower (24 fps) with the small rifle and the standard deviation was slightly better with the small rifle.

Let me preface this by saying that I’m not a grey beard when it comes to casting, but I’ve logged a lot of time behind 6PPC’s shooting short range (100/200) benchrest competition. I’m only saying that because I ruled out bench technique as a problem and the rifle can shoot sub MOA @ 100yards with J bullets.

So as it is right now, I’d say the Lyman boolit "as I am casting them" are not accurate enough for anything but tin cans at 50 yards.

And I think it’s the quality of the cast. My discard rate is pushing 60% to get what I could shoot. I have a Lyman 2660415 FN 55gr that I’ve put some time into. My records show that between 2.2 and 2.6 grains of Bullseye (1,095 to 1,325fps) I've shot multiple groups between .444 and .863 at 50 yards. And I can easily reach the lands with the 55 grain Lyman. The 37 grain NOE is jumping .038 to reach the lands so I don’t hold a lot of promise for that one.

But……(this is starting to sound like a soap opera isn’t it) the far cavity on the 55grain Lyman is not releasing it boolit worth a darn.

So if anyone is still listening I have two last questions.

Would I be able to use a brass brush (Harbor Freight) to clean the 44 grain mold with the Comet paste. I'm thinking there are contaminants stuck in the cavity.
And I promise this is the last question. What do you do about a cavity that won’t let go of its cast



So the plan is to scrub the mold once more, run the temp around 380, inspect the vent grooves in the mold to make sure they are clear and give it another go.

Thanks for listening to all of my whining, Bill.

PS. Maybe I should change my user name to Whining Bill.

17nut
12-12-2017, 12:55 AM
I bet the NOE is an aluminium mould and the Lyman is iron.
They are different beasts and need different casting techniques.
All my iron moulds like to run wery hot and as temp rises they start to cast perfect.

john.k
12-12-2017, 12:58 AM
If I knew ,i would tell you.I have a recent Lyman 314299 2 cavity,and no way will it release bullets when it gets up to temp.The first few come out with a few raps,but after that the bullets stick into either side of the mold,sometimes stick top/bottom,so opening the blocks leaves bullets crossed between the blocks.I have resorted to a brass pick that i hook the bullets from the mold,as no ammount of pounding on the handles will knock them out......I give up,and grab a RCBS 45/300,and start casting,the bullets fall from the blocks with an occasional shake of the handles......change to a Lee 429/240,same story,bullets fall from the blocks........I reckon its the steel molds.......Lyman no longer use cast iron.

Wayne Smith
12-12-2017, 09:01 AM
Have you monitored mold temp? Iron molds need to be run at a hotter mold temp. Alloy temp alone won't do it.

OS OK
12-12-2017, 10:17 AM
As far as accuracy, I shot eight 5 shot groups today with the 44 grain Lyman’ s and although a couple groups showed promise there would have been none under 1 ½” @ 50 yards. Today I was using Unique 2.5 - 3 grain (1,214 - 1,434 fps), half with small pistol and half with small rifle. Neither primer showed an advantage. Velocity was fractionally slower (24 fps) with the small rifle and the standard deviation was slightly better with the small rifle.
Let me preface this by saying that I’m not a grey beard when it comes to casting, but I’ve logged a lot of time behind 6PPC’s shooting short range (100/200) benchrest competition. I’m only saying that because I ruled out bench technique as a problem and the rifle can shoot sub MOA @ 100yards with J bullets.

So as it is right now, I’d say the Lyman boolit "as I am casting them" are not accurate enough for anything but tin cans at 50 yards.

And I think it’s the quality of the cast. My discard rate is pushing 60% to get what I could shoot. I have a Lyman 2660415 FN 55gr that I’ve put some time into. My records show that between 2.2 and 2.6 grains of Bullseye (1,095 to 1,325fps) I've shot multiple groups between .444 and .863 at 50 yards. And I can easily reach the lands with the 55 grain Lyman. The 37 grain NOE is jumping .038 to reach the lands so I don’t hold a lot of promise for that one.

But……(this is starting to sound like a soap opera isn’t it) the far cavity on the 55grain Lyman is not releasing it boolit worth a darn.

So if anyone is still listening I have two last questions.

Would I be able to use a brass brush (Harbor Freight) to clean the 44 grain mold with the Comet paste. I'm thinking there are contaminants stuck in the cavity.
And I promise this is the last question. What do you do about a cavity that won’t let go of its cast



So the plan is to scrub the mold once more, run the temp around 380, inspect the vent grooves in the mold to make sure they are clear and give it another go.

Thanks for listening to all of my whining, Bill.

PS. Maybe I should change my user name to Whining Bill.

You seem to be juggling a lot of variables at the same time (.5 grain changes in load & running std. & mag primers)...looks like your getting frustrated too. You know bench-rest, then...you know you can't make wide changes and expect to be anything but 'all over the map'.
Now...this is just me, but...this is what I'd do. I'd find the load that shoots off of one of your barrel nodes, you may have overlooked the fact that if you are not shooting off a node and thinking that you are...well, that group is not going to dial itself in, it will swell in and out but it will not continue to decrease in diameter until it becomes a 'bughole'.
Small subtle changes ='s small differences 'in or out' of the group...the casts you showed should get you to a barrel node, I can't see why they wouldn't because they're uguly...I'd find the node first and then do all the fine tuning from there. As far as speed goes, I'd look at that last, what you see when your on the node is what you get.

c h a r l i e

country gent
12-12-2017, 10:48 AM
I would polish the cavities by lapping them very lightly with tooth paste simichrome polish or flitz. A sharp square edge can cause a mould to grip or not release the bullets as can a rough surface. The above polishes will just smooth the surfaces with out removing much metal. It will also help if bullets are out of round some. The process for lapping has been posted many times on this site.
Cast several bullets as good as you can get from the mould and id as to cavity and pour
drill a hole in the base and glue a pin in then with epoxy. this is the stem to grip the bullet and turn it.
remove the sprue plate and clean the mould with solvent and a brush.
Impregnate no 1 cavity bullet number 1 cast with polish and gently insert into mould closing carefully.
I use a tee handle for tapping to grip the stem and use a tapping action 1/4 turn back and forth 3-4 times rotate 1/4 turn and repeat thru 2-3 rotations.
repeat thru the cavities with this lap.
Next impregnate a lapp from cavity 2 pour 1 and start on cavity 2 repeating above.
Repeat again with a new cavity 2 lap starting with cavity 1
then repeat with lapp from c avity 1 and starting with cavity 2.
By repeating with the laps and cavities it keeps the cavites very close to the same size and round. Use a very fine polish.
Clean mould good to remove the polish and cast some with it measure and see if its improved.
You can check surfaces with a q-tip. pull it thru thru cavities and over the edges, if cotton is pulled the surfaces are rough.
Even on steel moulds a light smoking may help. A new mould may take 3-5 sessions to build up the patina on the surfaces to really cast a good bullet. Some heat cycle moulds to accomplish this also. Heat to 400* let cools slowly repeat 3-4 times heating and letting soak a short time then turn oven off with blocks inside and cool down. This helps get the surface patina built up before casting.

Wm Cook
12-12-2017, 12:35 PM
About the 44 grain Lyman dropping ugly bullets; after reading the post last night I took a good look at the Lyman mold and even though it had been repeatedly scrubbed (boiling water/Comet paste) it showed what looked like a buildup in the cavity and on the sides with the vent lines. No pinnacle’s or rust cavities, just a thin film of crud. But the crud in the vent lines certainly didn’t help with the quality of the cast.

My guess is that is the imperfections I was seeing in the mold cavity coupled with the fouled vent lines affected the final cast. So right or wrong I took a chance and soaked the mold in a 50/50 solution of Rustol and water overnight to dissolve anything that might have been built up corrosion. After scrubbing them with the small brass brush I could remove some of the contaminants and things are starting to look shinny again. Actually it was improved to a large degree. Rustol and I are old friends and it sometimes takes a couple days of soaking to get it as far as it can go. As that’s happening I’ll continue brushing a couple times a day. By tomorrow this time I should have the mold as clean as I can get it. I guess keeping it from rusting will be my next battle.

Boiling water coupled with one more brushing with Comet and I might be able to salvage the mold.

After all of that and as cg suggested, I’ll probably bring both molds up to 400 degrees a few times in the oven to get the mold tempered and then set up multiple sessions to break in the mold once more.

For the 55 grain Lyman I'll take it through the lapping process described by cg. That might help that far cavity to drop. Thanks very much for those ideas.

And I’m also going to order a hot plate today for the mold. I believe 170 is the recommenced temperature? And I’ll start running the pot in the 380 to 400 degree range and monitoring mold temperature.

On a positive note I took time to empty and clean the pot as posted in a stickie. I can’t lay my hands on it right now but the description called for Hydrogen Peroxide and white vinegar while using a brass brush. That worked splendidly. It came out spotless.

I’m optimistic thanks to all of you. Thanks for being there. It's a good thing to have a source to go to when you hit a wall and within hours have multiple recommendations fro those smarter than I. Bill.

runfiverun
12-12-2017, 02:21 PM
don't scrub the mold with a brass brush it will score/scratch the mold.

as a BR shooter you know how little things make a big difference.
shooting the 22's are little things, any weight variances in the bullets will open group size.

gwpercle
12-12-2017, 04:41 PM
As for not releasing:
1. Run a Q-Tip all around the edges , any burrs will snag the cotton tip and can be removed . If the cavities edges are burr free.

2. Coat the cavities, top of block and underside of sprue plate with Liquid Wrench Dry Lubricant.
You can use the spay and wipe off excess or I apply a thin coat with a Q-Tip ( I have a little bottle of the Dry Lube ) Now I know this might sound strange, but if there are no burrs the Liquid Wrench Dry lube will make them just about jump out the mould...some don't believe me but try it just once and see.
I usually coat a cold mould, bring it up to casting temperature and start casting....usually this one treatment last the whole session. The stuff is one heck of a release agent !

I find Comet way too course for lapping a mould, I tried it once and stopped when I saw how rough it left cavities...automotive buffing compound followed by automotive polishing compound works much better than rough Comet or toothpaste .

Avoid brass brushes like the plague....they will ruin a Lyman mould !

Gary

243winxb
12-12-2017, 04:57 PM
High temperature will cook the mould clean while casting. Maximum pot temperatrue of a Lee pot will do it. Get all that misc stuff out of the porous iron. Frosted bullets is what to look for.

45-70 Chevroner
12-13-2017, 02:37 PM
The melting temp. of lead is around 600 degrees. Your temps must be off. Actual poring temps should be at least 700 degrees. At the temperatures you posted the lead would not even be melted.

MUSTANG
12-13-2017, 03:13 PM
Get an inexpensive hot plate such as this:

https://www.amazon.com/Cuisine-ESB-301BF-Maxi-Matic-Single-Electric/dp/B00C8C5I7I/ref=sr_1_5?ie=UTF8&qid=1513192252&sr=8-5&keywords=hot+plate

Rest the Lyman mold on the hot plate to warm to casting temps and keep temp up during the casting session if you set the mold aside for a few minutes during a casting session.

John Boy
12-13-2017, 03:54 PM
The Lyman 225438 mold - I'm guessing - looks like a reside in the cavity from a lube that was used on the mold - excess lube when lubing the pins? Did you put any lube in the mold and if so. what was it? If it was beeswax - that's the reside inside the cavity

gwpercle
12-13-2017, 04:09 PM
For grungy crud cleaning nothing beats acetone soaking and a tooth brush scrubbing . Gently use a 0000 steel wool pad for the stubborn spots .
Gary

MT Gianni
12-13-2017, 08:10 PM
Ditto on the hot plate for iron molds and it improves aluminum as well. I would pour as hot as I could this time of year in MT to keep the Lyman mold warm with a small cavity and large block. Run your lead up to almost 800F but not over and try to cure any impurity. After you fill the cavities dump another ladle of lead across it as it "cools". If there is a contaminant in it, burn it out.

Ia.redneck
12-13-2017, 11:54 PM
Did you try holding the mold against the nozzle? (pressure casting)
I've used that to fill out a stubborn mold

rintinglen
12-14-2017, 03:19 PM
There is a sticky on polishing out cavity irregularities by an AnZac fellow named Weet or something like that. Read it and give it a try, it may not make your rifle shoot better, but it will make your mold cast better.
: "Expanding a boolit mould the "WEET" method". (In parts) In the Molds maintenance and design section.

BigBore45
12-16-2017, 01:17 AM
Looks like the mold wasn't hot enough. Warm it up a bit on the pot before you cast.

HangFireW8
12-23-2017, 10:22 PM
The melting temp. of lead is around 600 degrees. Your temps must be off. Actual poring temps should be at least 700 degrees. At the temperatures you posted the lead would not even be melted.

He said he tried 290 to 380:

290C = 554F
380C = 716F

I think he's in the right ball park, but it wouldn't hurt to try a little higher. Better venting and pre-heating (as mentioned), and/or polishing (as mentioned), the answer is in there somewhere.

bigcountry022885
12-23-2017, 10:45 PM
He said he tried 290 to 380:

290C = 554F
380C = 716F

I think he's in the right ball park, but it wouldn't hurt to try a little higher. Better venting and pre-heating (as mentioned), and/or polishing (as mentioned), the answer is in there somewhere.

Most of my molds wont fill good unless I'm at least 720 so I try and keep my pot between 720 to 740 but I also have a temp controller and I have a hot plate to put my molds on so they are close to running temp befor I even pore I usually will through a few bad to start and then it's gold from there on out


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