How much variation in bullet weight is too much?

[Noah Mercy]

I'm just getting started in loading BP in my 45-70 and I cast some bullets from a Lyman 457124 mold. I have a group of 15 bullets with weights varying about .7 grains from lightest to heaviest. (I tossed a few underweight ones that I suspect had voids.) Is this too much to expect good long-range accuracy from? If this is too wide a spread, what should I be looking for as far as tolerances? I appreciate any help, pards.

[Cuts Crooked]

Howdy Pard,

Fer long range stuff like that I don't accept ANY variation. I 'spose there may be an allowable limit, I never looked into the matter, but I feel better about zero as the number! I also keep only the heaviest, never sorting them into weight groups. Don' know if this is the norm, it's jist what I do. (BTW, I'm not the best shot in the world, nor do I have all that much experiance behind me. I just bought my first Buff gun last year so my opinion may be suspect)

Fer main match calibers I don't even bother to weigh them. So far I've been very happy with performance in the main match guns just as they drop from the molds.

[Noah Mercy]

Thanks, Cuts. I agree about main match stuff. I get about a three grain variation in my 250 grain 45 Colt bullets using straight wheel weights, but the groups I get are small enough that I can hit a 200 meter ram every time with my handguns if I hold my tongue just right. (With the rifle, it's not even a challenge.) If you don't mind me asking, what percentage of your bullets come out identical? I'm using a very old mold (hey, wasn't that a brand of cigs?) and I'm wondering if I need to just go and buy a new one, or if it's my casting technique at fault. (I'm only getting about 20% of my bullets to drop at an identical weight.) My buff gun alloy consists of 8 pounds of pure lead with 2 pounds of linotype. With this mix, smaller handgun cartridge bullets cast great, but I'm not happy with the bigger rifle slugs.

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[Cuts Crooked]

I count myself lucky if I get 50% at the heavy/exact weight. However this is with my inexpensive Lee molds. My casting tech is to place the uilt in guide on my Pro 4 so that it just clears the mold and lift the operating rod all the way up until metal pools on top of the mold.

I used to pour with a ladle and my percentages of perfect slugs were much lower. Others tell me that they have better luck with ladle pouring than they do using a bottom pour pot!?!?! Like I said, I ain't no xpurt!

In an aside, I have one of the new DD/PRS multi cavity molds from LEE in 405 grain configuration. I was surprized to see that my percentage of good slugs remains about the same. I was expecting more variation with the six cavity mold!!! If I were a major competitive type I would look into buying some of the higher dollor molds like RCBS or even a good custom mold. Unfortunately I cannot find a custom makere who can turn out a PRS style smold other than Lee.

[Delmonico]

I allow 1/4 grain under my standard for my mould.  Anything over will have a bump on the sprue.

The percent is very small with a standard of 509 grs.  (RCBS 500 BPS)  I use 24-1.  I reject about 50% on them, but when I miss it ain't the bullets fault.  The 457122 mould I use for huntin' loads I allow 1/2 grain. 

Cuts, don't worry bout what works for others when castin'  do what works for you.  My different moulds often require different styles ta get what I want.  My RCBS BPS mould requires I inject the lead in the sprue by holdin' it to the spout and liftin' and holdin ta the count of 10.  Now I have been told this won't make really good bullets and it won't with any other mould I own.  But I end up with about 99 percent that most folks would be tickled about. 

Never fear, the Lee moulds will make as good a bullet as any other non-custom mould.  Just wish they made some styles they don't, would same me money, no I would spend the same amount of money but I would have more moulds ta show for it.

[Cuts Crooked]

I would spend the same amount of money but I would have more moulds ta show for it.

LOL!!! No kidding on THAT score! I'm squirling away the pennies fer a new custom mold once the design is complete. Dick Dastardly, of DD/PRS fame, is working up a new 500 grain design in a semi-spitzer style, with bore riding nose and a pair of those fabulous PRS style lube grooves. (those are the greatest thing to come down the pike in a long time where BP is concerned..at l;east to my notion!) I GOTTA have one of those! My 405 grainer is the cats pajamas when it comes to shooting long strings without bore maintainance! But it's abit light fer the really long stuff that needs to be knocked over. My biggest concern is case capacity with these. Those large grooves take a up a lot of room that is desparetetly needed for powder in the 45-70 chambering. DD has commented that he is looking at a three groove design as a possibilty, and that would make it a No Go for me. All I can do at this point is wait & see.

I am a bit unhappy with Lee over their new policy concerning custom molds....they want 100 )I think) orders before they will waive the set-up fee now. Used to be 25. 

[Noah Mercy]

With regards to case capacity with longer bullets...if ya' don't mind using a BP sub, Hodgdon 777 will allow you to reach higher velocities than an equal quantity of BP. Another option is to use a compression plug from Buffalo Arms to squish the powder down .2-.4" without deforming the bullet by using it to compress the powder. This has the added advantage of helping the powder burn very efficiently, leaving almost no fouling. (Check out my thread about the results I got with my 45 Colt using a plug to compress the BP.) If I can scrape together a few pennies myownself I intend to buy a Hoch nose pour mold. I think they're some of the finest molds made and they have a lot of good designs available. I'd love to get my hands on one of the 405 grain prs molds, though. (I like my Lee molds and get great bullets from them.)