Weight variance in multi cavity moulds
- Thread starter shuz
- Start date
CWLONGSHOT
Well-Known Member
Virtually none.
ESP ones made on new equipment. Variances have not been visible for a long time.
ESP ones made on new equipment. Variances have not been visible for a long time.
Michael
Active Member. Uh/What
That is what I call good timing. Not sure if a 2-cavity mold would be considered "multi", I just finished weighing out approximately 220 Saeco 645's, and 125 Saeco 745's that I cast up this last week. 95% of slugs from the front cavity ran between 417-418grs, with the rear running 418-419grs. On the Saeco 745, the average difference was 0.5grs difference between the 2 cavities, 530gr +/-, but the extreme spread for each was larger by 1gr. Could have been me, different day, but same alloy of consisting of 24/6/1- lead/COWW/tin. Cast with a dipper, 6 secs on each cavity to help ensure complete fill. Sprue cut with gloved hand whenever possible, no dimples, just nice smooth smears.
Some folks don't weight sort at all, for me, it depends. Getting ready for a match in UT in early June, life starts at 200yds and ends at 1125. Had few out of each mold the were 2-3gr light, but visually looked perfectly fine. I would rather weigh than wonder if the miss was me, the wind, or the bullet.
Some folks don't weight sort at all, for me, it depends. Getting ready for a match in UT in early June, life starts at 200yds and ends at 1125. Had few out of each mold the were 2-3gr light, but visually looked perfectly fine. I would rather weigh than wonder if the miss was me, the wind, or the bullet.
fiver
Well-Known Member
most of your newer molds are cut on a CNC machine with the same 'cherry'
cherry would most definitely be a misnomer, it looks more like a ??? well,, it looks more like a skinny routing bit that got stuck on a nail and twisted out of shape.
old school steel molds will generally be more likely to have a variance, since i usually make a lap and cut all my own cavities before actually doing a production run with them i keep my variances down pretty good.
i do have a 2 cavity 22 cal rcbs mold that casts .1gr different between them and it kind of drives me nuts when i weight sort them.
cherry would most definitely be a misnomer, it looks more like a ??? well,, it looks more like a skinny routing bit that got stuck on a nail and twisted out of shape.
old school steel molds will generally be more likely to have a variance, since i usually make a lap and cut all my own cavities before actually doing a production run with them i keep my variances down pretty good.
i do have a 2 cavity 22 cal rcbs mold that casts .1gr different between them and it kind of drives me nuts when i weight sort them.
I tried this with one of the 1st NEW 2cav mold I ever bought, #452424. I was in such a hurry to cast with it that I rushed right home and fired up the lead pot.
While it heated up I cleaned & dried the mold. Stuck on the handles and started casting. The front cavity was a little sticky, bullets from the rear cavity jumped out of the mold without a tap. Was using COWW with about 10% Linotype. Perfect fill out, some weighed 260gr, some 261gr. Didn't do anything to the mold for next time. Just dropped bullets from rear cavity on left side of pot. Bullets from front cavity on right.
Out of 100 rear bullets, the culled weighed 261gr, 100 front bullets, the culled weighed 260gr.
I shot them out of a NM Blackhawk, unsorted; 2 inch groups at 25yrds. Sorted, couldn't tell the difference. Over 8.0grs of Unique, a load under max in the Lyman handbooks since before I was Born.
Why do I remember this from 46yrs ago ? When I can't remember the guy's names who bunked on either side of me in Recruit training, 5yrs earlier ? 5-6 concussions.
By Wednesday I won't remember this.
While it heated up I cleaned & dried the mold. Stuck on the handles and started casting. The front cavity was a little sticky, bullets from the rear cavity jumped out of the mold without a tap. Was using COWW with about 10% Linotype. Perfect fill out, some weighed 260gr, some 261gr. Didn't do anything to the mold for next time. Just dropped bullets from rear cavity on left side of pot. Bullets from front cavity on right.
Out of 100 rear bullets, the culled weighed 261gr, 100 front bullets, the culled weighed 260gr.
I shot them out of a NM Blackhawk, unsorted; 2 inch groups at 25yrds. Sorted, couldn't tell the difference. Over 8.0grs of Unique, a load under max in the Lyman handbooks since before I was Born.
Why do I remember this from 46yrs ago ? When I can't remember the guy's names who bunked on either side of me in Recruit training, 5yrs earlier ? 5-6 concussions.
By Wednesday I won't remember this.
CWLONGSHOT
Well-Known Member
I had one that left a "mark" lasting almost two months!!! Yup I have had three that I know of as well. None fun.
Concussions take a ravaging toll often times decades to see repercussions of them.