Casting with Lyman 452374

[Hardatwork]

When I cast with WW only my mold Lyman 452374 casts at 450" and 451.5". I need 452" What can I do to get the 452"or even 453" When I add Linotype I can get 451" to 453" but then my BHN is to high please I can use some help. I have heard of lapping the mold but what is it and how do you do that. Will it help.
Thanks

[bobthenailer]

try beagealing the mould or polishing the cavites with a dremmel tool and a cotton bob with some polishing paste. lapping the mould with a bullet cast from the mould with a rod inserted in the base of the bullet but dont close the sprue plate and pure the bullet and put compound on the bullet

[Hardatwork]

Will adding Tin increase the size of my boolits or casting temp. Just trying to work this out with out changing my molds they make a vary nice boolite it is just a little small.
Thanks

[fourarmed]

Adding tin will increase the size of the boolit, but probably not more than .0005" if that. Get a roll of aluminum duct tape at the hardware store. Cut strips about 1/8" wide and stick them below, between and on either side of the cavities on one face of the mold. That will give you your extra thousandth without modifying your mold. Don't get the aluminum FLUE tape. That will boost diameter about .003".

[dubber123]

To lap a mould, basically drill a hole in the sprue end of a boolit, thread a screw in. Chuck the end of the screw in a drill. Put a SMALL amount of an abrasive compound in the cavity, or on the boolit, (some use as fine as toothpaste, I use 320 grit valve lapping compound).

Gently close the mould over this contraption while it is spinning in the drill. Stop VERY frequently to clean any compound from between the mould faces, and to re-apply if necessary. The first .001" usually comes out very quickly. If there was any hesitation of a boolit to drop, be prepared to be amazed at how easily they will drop after this treatment.

[35remington]

Do you know for sure that they're too small for your barrel? How do they shoot as they are now?

[Hardatwork]

My Taurus is in for repair so last time out I had Boolits that were to hard 22BHN. heavy leading. I have cast new with just WW that are 11BHN and have not tried them but when I took Linotype from the mix the size got smaller 450" to 451.5 so I am trying to figure out how to get them back up to 452" or above.

[Hardatwork]

Thanks Guys I got my pistol back from Taurus and went to the range to try my softened boolits out much better but still some leading. my question is now would you try to soften the boolits more or increase the powder charge some . I am using Unique at 5.5 Gr. speed is 750 to 776 FPS.
Thanks

[44man]

What causes leading is a funny situation, some use softer boolits and some use harder. I use harder, from 18 to 22 BHN in all of my revolvers and also use different sizes of boolits with no leading. For instance I use .430 to .432" in my .44. My throats are .4324".
I have never had a problem with leading unless I made boolits too soft or used a poor lube. All of my loads are heavy hunting loads though. It does not seem to matter if a boolit needs to be forced through the throats with my thumb or if it drops through by itself. I might get a few tiny pieces of lead on the first patch and that will be all.
I shoot for months without a change in barrel condition and only clean when fouling makes the cylinder harder to turn.
I can not answer the leading question as it pertains to your gun. In my case, a few thousandths in boolit size has no effect at all.
Lack of case tension on the boolit might cause leading if the boolit is blown out before the powder burns right. There might be a lot more reasons for leading because of loading practices instead of boolit size or hardness then we realize.
I think more work needs to be done instead of blaming one thing on leading.

[Hardatwork]

So any suggestions as to what my next step would be. I lapped my mould did not see any change in size. maybe I should try a different powder. I have heard that Winchester 231 is a good choice. I cast for my 357 and 44 and there is no leading but I use gas checks with those. wouldn't it be nice to have a Range in the back yard . IT would save a lot of time and gas going back and forth gust to check something out.

Thanks for your time.

[runfiverun]

i hate to say this, but... i bet this is a new mold and is becoming a common theme with lyman now days.
if it is call them and tell them you have one of their latest in their series of molds that are too small.
and you want it fixed.
if it ain't, i would up the powder charge of unique to 7 grains.
or try the faster powder to try and bump up the boolit.

[Hardatwork]

It is a Lyman 452374 Got it about 4 weeks ago. Is this under size a problem with new Lyman molds? I have others that work fine.

[Hardatwork]

I called Lyman today and told then that the boolits that I had cast with the mold were coming out at 450 and 451 and they want me to send them a sample So if this is the norm for them then what is the use. wont the next mold be the same what would you do if you were me. I got it from MdwayUSA and I am thinking about calling them to see what they would do.

[mtgrs737]

Do the boolits come out frosty or shiney? If they are not frosty then you may be able to get a little larger size boolits by heating up the mould more to get the thermal expansion of running them hot. Let us know what you get when they are frosty looking.

I just bought a New Old Stock Ideal 429421 two cavity at the last big gunshow and it is dropping .434" using WW's! I have heard that the new Lymans don't cast much oversized and that is why I bought the NOS Ideal.

[Hardatwork]

I took the temp. up to 800 nice frosty boolits still under size. I guess I will half to send it in to Lyman for repair.They told me that it would take 3 weeks to repair. That sucks Took 4 weeks to get it from Midway it was back ordered and now I am going to weight again Just my luck. :coffee: