Mould casts too small

[Dead Dog Jack]

What is the standard list of troubleshooting when your mould drops rounds that are smaller than the actual mould size?

I'm not an expert at casting, rather a newbie. My rounds are measuring .004 smaller than I expect them to be. (I measured them about two weeks after casting them) You don't think they could be shrinking, do you? I don't quench.

Any general ideas would be great.

[longbow]

In my opinion 0.004" is a lot.

What is your groove size and what size are you casting?

If the mould is casting undersize from what it should then you should check with the manufacturer to see if you can get a refund or replacement.

If it is casting to spec +/- a bit but you have a large groove diameter you could try Beagling which should increase diameter by up to 0.003".

You could also lap the mould but in my experience 0.004" is a lot to lap out.

What you should be aiming for is boolits at 0.001" or larger than groove diameter.

What make and model for the mould?

What gun?

What is the groove diameter?

Longbow

[stubshaft]

What mold are you using? what alloy?

[Echo]

If it's a Lyman, forget it - they wouldn't re-cut my 452374, but offered to replace it at a considerable saving. Problem I saw with that scenario was that I might get another undersize mold.

[geargnasher]

Sounds like a Lyman mould to me. Throw it in the trash and spend your good money elsewhere, like RCBS, Lee, Saeco, or one of the many excellent custom mould makers.

Gear

[Dead Dog Jack]

The mould is an RCBS 45-265-RNHB. I was under the impression that it was supposed to drop .455 bullets (I'm reloading the Webley cartridge), but it is dropping .450 and .451. Perhaps I had the wrong impression to begin with? The gun is a Colt New Service in the original .455.

The lead is from sheathing taken from a building floor when they were tearing it apart. I didn't add anything to it.

[Ben]

I'd feel a lot better about my chances at the roulette
wheel vs. buying a new Lyman mold.

The old IDEAL's are another story........

Ben

[mooman76]

If the mould is dropping too small RCBS will make good. The lead you are using sounds soft and soft will drop slightly smaller but not .004/5 smaller.

[HenryC460]

The mould is an RCBS 45-265-RNHB. I was under the impression that it was supposed to drop .455 bullets (I'm reloading the Webley cartridge), but it is dropping .450 and .451. Perhaps I had the wrong impression to begin with? The gun is a Colt New Service in the original .455.

The lead is from sheathing taken from a building floor when they were tearing it apart. I didn't add anything to it.

MiHec has several Brass 4-cavity 45-200 SWC moulds that are dropping 0.457" boolits with straight wheelweight alloy. I don't know the price, but they appear to be a few he made while setting up to make a run of 0.454" and 0.452" moulds. Maybe they're bargain-priced, seeing as they weren't what he planned on making.

It's post #145 on this thread:

http://castboolits.gunloads.com/showthread.php?t=116811&page=8

[Bob Krack]

The mould is an RCBS 45-265-RNHB. I was under the impression that it was supposed to drop .455 bullets (I'm reloading the Webley cartridge), but it is dropping .450 and .451. Perhaps I had the wrong impression to begin with? The gun is a Colt New Service in the original .455.

The lead is from sheathing taken from a building floor when they were tearing it apart. I didn't add anything to it.
I have an RCBS 45-255-Keith style and it drops at .452-.453. Mostly .452.

The people down on Oro-Dam Boulevard in Oroville, CA are great to deal with. Call them or communicate however you must and see what you can work out.

Been there several times (lived 10 miles away) and they were always great.

Bob

[foxtrapper]

What are you using to measure your bullets? Dial calipers are not the best tool to measure, pick up an inexpensive micrometer. Good luck!

[243winxb]

The lead is from sheathing taken from a building floor when they were tearing it apart. I didn't add anything to it. You could try using an alloy with a high antimony content or Linotype, this will increase the diameter. But .004" is a lot to increase.

[JeffinNZ]

I've said it before, I'll say it again. Married it. The girth will increase naturally.