new caster learning

[scion19801]

well i tried a few changes since my pot is pouring better. lowered my temp down to 790 from 850. now i'm not sure whats going on. pellets still weigh in at .2 grains of variance. turned down temp due to a lot of whiskers on the pellets. that cleared up with the temp drop. but now my accuracy is gone, even after a deep clean on the barrel. not sure if its due to the slightly lighter pellet drop weight or if something is up with the scope. seems like when i adjust the scope it requires a few taps to get it moving. so that can't be good. almost like the erector tube is sticking.
shots on paper are scattered as well. not as tight as they were. And beyond 72 yards the pellets destabilize.

[scion19801]

figured out my issues. Bad batch of pellets. they look good but something isn't right with them. so they are going back into the pot and my temp is going back up. seeing alot of outside whiskers and inside base not filling out right at the pin (only on rear cavity) inside. I think the amount of flow i'm now getting is the cause of the outside whiskers.
Then second issue. my scope all the sudden has taken a dump. wont track or adjust as it should. have to tap it a few times with any adjustments made in order for it to change locations. NOt cool. Replacement scope should be inbound soon. Luckily i have it where it should be after trying a previous batch of pellets.

[Wayne52]

I tried casting with 1% tin and get whisker's with my pot, eventually I'll get one that I can control the temp with, just a small 4lb pot. I cast everything with pure lead from Rotometals.
The one that I have now is an old Lee 275 watt.

[scion19801]

i just finished a batch at 825°F. still getting the occasional bad inner base, and both cavities were doing it this run. as long as i'm careful to cull them out, then roll test and they all hit as expected. weight is still down on them at 26.6-26.8 gr. still more experimenting to do to get them back where they were. but things are improving.

[Hoosier Daddy]

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[triggertreat]

I typically only get whiskers when pressure pouring at 850°.  At 735° I haven't seen any whiskers.  I stopped doing the pressure pour method as I prefer to coat the plate to keep the mold and plate temps up.  Pressure pouring lets the mold cool down too quickly when aluminum.  Probably a better deal with a brass mold.  My only issue with the pellets is getting the meplat to cut clean and even.  I don't know how critical that part is in flight.

[Wayne52]

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Scott are you thinking about doing some casting ?

[scion19801]

so here is the best pic of my latest defect that i'm dealing with.
I adjusted the pot back to 850. I can feel the heat coming off my mold through my glove so i know mold temp is about right. it would seem it is a cold pin issue??? but i don't know how that can be. I get a few good pours nice inner base then it will drop a few as pictured. I wonder if i should scrub the mold down again? I've tried smoking both the pins and the cavities and it doesn't seem to help any.

On another note. I talked to Al @ NOE. wanted to know if the latest batch off 250-27 hunters were dropping on spec. He's gonna check and let me know. If they are, I'm gonna pick up another mold. I also inquired into the 250-41-FN slugs. they are in the que to be done for resupply, but he couldn't give me a time line on them. That is my next slug I wanna try, as i think they would be really good in my Airforce condor I have on order.

[Madd Hatter]

Have you polished the pins yet? I polished mine up so smooth I have problems picking them up with my old man fingers. The pellets fall off the pins with just a shake of the mould.

[scion19801]

No i haven't. But i also just found damage. Kinda bummed as now i got to get a new mold again. Right at the base of the front pin where it seats to form the bottom of the pellet mine is all worrbeld out and got a bad nick somehow on one spot right at the mold halves on the sprue plate side where the pin seats to seal the bottom. I always gently shake my mold upside down and slowly close it. so not sure how exactly it could have happened. I do recall dropping it on my rug, but was sure i didn't see any damage. I did have my rear pin go super tight on me as well last night while casting. knew something was up as pellets started getting harder to drop out in the back half cavity only. rear pin seat also shows sign of it starting to worrble out as well.
I got the new mold ordered. now i just hope this one is closer to spec. my current one was dropping .02" short.

[Hoosier Daddy]

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Scott are you thinking about doing some casting ?

I am thinking about it.
Reading threads like this fine one here.

[triggertreat]

so here is the best pic of my latest defect that i'm dealing with.
I adjusted the pot back to 850. I can feel the heat coming off my mold through my glove so i know mold temp is about right. it would seem it is a cold pin issue??? but i don't know how that can be. I get a few good pours nice inner base then it will drop a few as pictured. I wonder if i should scrub the mold down again? I've tried smoking both the pins and the cavities and it doesn't seem to help any.

On another note. I talked to Al @ NOE. wanted to know if the latest batch off 250-27 hunters were dropping on spec. He's gonna check and let me know. If they are, I'm gonna pick up another mold. I also inquired into the 250-41-FN slugs. they are in the que to be done for resupply, but he couldn't give me a time line on them. That is my next slug I wanna try, as i think they would be really good in my Airforce condor I have on order.

You can put a very tiny amount of two cycle oil on the tips of the pins to help.  I have noticed when I get mine too hot they will stick.  They say the lead shrink's when it cools from being so hot.  As mentioned previously, I cast my last batch of .249 slugs at 735°.  I didn't have any slugs sticking to the pins not once.  They fell right out each time.  I didn't polish nor clean the pins or use any oil on the pins...Just started casting from the last run days ago.

I sold my 250-41-FN.  I never could get those to shoot straight even after cutting off my choke on the Marauder.  I also received PMs from knowledgeable people telling me they are no good, and that nobody has had any luck with them.  All hearsay to me, but I know they're no good for groups in my particular Marauder.  I was finally done with them after they wouldn't cycle in my FX mag either.  Not their fault on that, but still a no go to keep around.  Maybe you can get them to cooperate in your gun???

[Madd Hatter]

No i haven't. But i also just found damage. Kinda bummed as now i got to get a new mold again. Right at the base of the front pin where it seats to form the bottom of the pellet mine is all worrbeld out and got a bad nick somehow on one spot right at the mold halves on the sprue plate side where the pin seats to seal the bottom. I always gently shake my mold upside down and slowly close it. so not sure how exactly it could have happened. I do recall dropping it on my rug, but was sure i didn't see any damage. I did have my rear pin go super tight on me as well last night while casting. knew something was up as pellets started getting harder to drop out in the back half cavity only. rear pin seat also shows sign of it starting to worrble out as well.
I got the new mold ordered. now i just hope this one is closer to spec. my current one was dropping .02" short.

Might have happened when you dropped it ☹️

[scion19801]

could be robert.

tiggertreat,
you may be onto something about the shrinkage. I think that may be whats going on. I had that same issue again when trying to cast up some more slugs. after cooling a bit they'd get a goofy indented circular spot on the outside and then it would cast ok, then get it again for a few, then clear up. I'm thinking its due to the lead being too hot. so gonna try a lower temp tonight and see if it clears up.

[scion19801]

ok. finally making some progress. Kinda! got a decent set of calipers that i can trust. checked them against micrometers and they both match. so i then checked my slug mold. Well cavities are nice and round, and at .250". Now how or what do i need to do to try and limit shrinkage? checked some of my different slugs playing with temps. slugs are all undersized. majority are .248" just a little out of round here and there.. this isn't good for accuracy.
Last cast session i noticed pulling in the corners when the sprues get cut. so I'm sure that is the out of round cause. wondering if I need to slightly open the sprue plate holes into the cavity or if that's not a good idea. Biggest thing it to getting the shrinkage amount limited. Do i need to go colder with lead or hotter yet to get more into the cavities and try to offset the shrink?

[Mark Davis]

My best weapon against shrink is a large puddle on top the sprue plate.
Difficult to achieve with fast flowing lead coming out of a bottom pour pot.

[scion19801]

new pellet mold arrived today. Hmm few changes. No longer do you get the blank pin. No issue there. Old pellets kinda fit in the new mold, except there is way more meat at the top sprue area. So the old pellets are short. Also old pellets don't fit the base pins. Short there as well maybe. I may have grabbed a short base pellet. hmm. Have to double check that tomorrow.
Got the first thermocycle in process. Doing cool down now. Burned up a cheap temp probe. Oops hit 395°F and went to 89.6 degrees. Opps. Found the limit for that probe. Now to find a probe that will fit and be comfortable to keep in place while casting. But then again touching the mold with my welding glove. I know I've never felt any of my molds get that hot. Quite warm, lol.
Guess I don't need to worry about my molds being too hot and now know I can really get them cranking. So it would appear I've been on the cooler side as far as the mold temp goes.

[triggertreat]

My best weapon against shrink is a large puddle on top the sprue plate.
Difficult to achieve with fast flowing lead coming out of a bottom pour pot.

+1  I leave a large puddle on each pour and watch for it to drawn in leaving a dimple to indicate a full fill.  This also keeps the cutter and the pins hot between cuts and refilling.  I find that if I pause to cut the sprue for about 10 to 12 seconds, the mold really heats up well, and can adjust the pause or the opening of the mold based on the drops sticking or not.  Basically broadly regulating the mold temp.  Also, the large single sprue cut is easy to catch by hand and toss back into the pot.

[scion19801]

just checked the new pellet against the old. oh i'm a happy person. the old pellets were .284" -.285" long and weigh around 27.2 gr. the new ones are .3" and 27.8 - 28 gr. this was with 800*F lead temp. way closer to spec now. Now i hope my accuracy just got way tight with these now.
did a quick few clips on my slug tune. at 50 yards i could see several follow the same spot , just a touch high and left of  my 1" target spinner. did get a couple to connect with my 6" steel target at 100 yards. I'm sure shooting these on my slug tune has them way over speed. but scope alignment isn't far off between the two.

edit:
new pellets are traveling at 878 FPS on the slug tune. oh man. Does this mean i just found the sweet spot for both slugs and pellets using the same tune? I think i did. I certainly hope so. then it will be just finding the difference for sighting in the pellets compared to the slugs. then I should be able to easily make a few scope click adjustments and go back an forth easily. This is what i've been hunting for...

[scion19801]

oh my... I think i finally found my holy grail settings. I have only a 10 click elevation adjustment to switch between slugs and pellets with my gauntlet...Finally got it dialed in. So lower left is slugs and so is upper left. others are the new pellets. mind you i didn't season or clean the barrel between projectiles. shot a clip of slug to pellets to slugs to pellets. only change was scope turret elevation of 10 clicks, back and forth between the two.
shows scope tracks pretty good. pellets really tightened up. but the other day was getting way tighter slugs groups, which i'm sure is from barrel needing to be cleaned again. kind of a accuracy torture test to jump back and forth.
target was at 33 yards which is the zero for both slugs and pellets.
slugs at 37 grain 795 Fps
pellets at 28 grain 878 Fps