a question about cast bullet weight

[sam54]

cast both 429421 (lyman manual weight 245 grains) and 358429 (lyman manual weight 168 grains)

i am using wheel weights with 2 % tin in NOE molds.

my weights come out heavier than the manuals at 260 for the 429421 and 179 for the 358429

is this weight difference enough to reduce the recommended powder amounts listed in the manuals? if so is there a percentage difference i should use as an adjustment?

i get sticky extaction with the 358429 at 13 grains of 2400 (using sw 686)

the lee tl 430 240 comes out at 243 grain when i cast

[Moonie]

Always begin at the bottom and work up. Never assume top loads (or even medium loads) are safe in your firearm just because it was in the pressure barrel the manual manufacturer used.

Also note, Alliant shows 12.5gr as a max load for 2400 with 180gr. 11.3gr as a starting load. In fact I'm showing nobody shows over 12.5gr for 2400 with any projectile in the 180gr range.

[Larry Gibson]

The Lyman 429421 listed weight is with bullets cast of linotype. Your alloy has a larger % of lead and there fore would cast heavier bullets. COWWs + 2% tin run right at 255 gr when cast in my older Lyman 429421 mould.

The question then is what alloy is your NOE 429421 designed/cut for?

As mentioned we should always work up loads. the max expected load should be based on the weight of the actual bullet used not the numerical design number. 12.5 gr of 2400 is a max load for a 180 gr cast bullet regardless of the design and that really should be worked up to just to be safe.

Larry Gibson

[bangerjim]

Cast 'em and shoot 'em! I do not ever worry about slight variations in weight as different alloys yield different weights. The "book" weights are only an estimate as far as I am concerned.

Start low and work up.

banger

[LAH]

If you begin with starting loads you'll be alright. I have very few molds which cast at advertised weight.

[sam54]

good morning all and thanks for your reply's

the NOE mould that i referred to as 429421 is NOE 434421 245 SWC. NOE ally type is wheel weights and their listed weight is 258 grains (mine come out at 260)

the NOE mould that i referred to as 358429 is NOE 4360429 168 gr SWC. I cannot find the recommended NOE ally type. their listed weight is 168 grains (mine come out at 179)

If i understand the comments I received is that work up the load and pay more attention to cast bullet WEIGHT as listed in the manuals not mould type (i.e. 358429).

As an example my Lyman manual list 2400 for a 265 grain 44 rem mag bullet mould at 18.8 to 19.8, while the 245 grain mould is 18.5 to 20.6.

[bedbugbilly]

I am a "low tech" caster - I primarily use "range lead" so the alloy varies from batch to batch. As already stated, start at the low end of data and work up - the #1 rule of hand-loading.

But as far as boolit weight . . . I wouldn't know what to do if I ever had a boolit drop the exact same weight as the Ideal/Lyman manual says the mold is supposed to drop. Not being "smart about it" - I'm just saying mine never do. I can take a 100 boolits from the same casting session, same pot of metal and weight them all and they will vary in weight. I just follow the printed data for that particular mold given in the Lyman Cast Bullet" manuals that I have and they all seem to work just fine.

Granted . . . I have known and shot with shooters who are OCD about it all - they weigh each one and try to use all the same weight and scrap the rest back into the pot. More power to 'em - but I don't shoot competition any more and being that picky takes all the fun out of it - IMHO. Pistol or rifle - and all I shoot is cast - I really do not notice any difference in the performance/accuracy of my re-loads if the boolit varies in weight by a couple of grains or less.

[bangerjim]

^^^^^^^^^^^^AMEN, brother^^^^^^^^^^^^^^^^^

banger

[Old Coot]

You have to consider something else. The faster you cast and the hotter the mold is the larger and heavier the bullet will be.
Remember that old science experiment on thermal expansion: There was a steel ring and ball on seperate handles. The ball would not go through the ring when at room temperature. Teacher heats up the ring on a gas burner and the ball will now pass through the ring. Teacher lets the ring cool and ball will not go back through the ring.
The same thing happens with your mold. The hotter you get it and the faster you cast the larger the cavities will expand to.
Brodie

[CHeatermk3]

I could be mistaken but I think all of NOE moulds (if you click on the pic of the boolit) list the alloy as Wheelweights.

[mac266]

The weight difference is not because of a planned error in the manuals. Rather, it's just a difference in the exact alloy you use versus what the publishers used. That is why it is important to use a consistent alloy all the time -- the more consistent your alloy, the more uniform your bullets will be, the more accuracy you can expect. As others have said, your casting temp, rate of production, and mould temp all affect the bullet's size (and thus, weight) when it's dropped. So there will always be variances between what you do and what the book says. Just make sure you're consistent. Secondly, as others have said, the weight difference is one of many reasons to start at the bottom of your load charts and work your way up.

[BwBrown]

The factors that go into the variations - your mold using your alloy at the temperature of the day etc. etc. - are part of the real world reason why your rifle will shoot the best groups with 35.7 gr of Superblast7 and mine prefers 35.8

SO MANY variables! But using proper safe reloading procedures, a few tenths of a grain of your projectile combination (cast bullet, lube or powder coating, gas check) will seldom get you into trouble.