30 cal hollowpoint?

GEMIHUR

Member
I'm impressed, guys!
You've shown much on the expanding influence that a hollow point's depth of cavity has to do with it's performance.
Thanks for the schooling.
 

JWFilips

Well-Known Member
For target work I would always choose a HP version of a bullet Then it's solid counter part
The balance of the bullet is better thrown to the base the the mid point.
This is just my observation
 

fiver

Well-Known Member
that's a very good observation to make JW.
all of my drawn designs are rear biased, but not h-pointed.
 

L Ross

Well-Known Member
For target work I would always choose a HP version of a bullet Then it's solid counter part
The balance of the bullet is better thrown to the base the the mid point.
This is just my observation
Tis a pity making HP bullets is such a ginormous pain in the behind. Single cavity is bad enough, dealing with that pin, and heat control is just too tedious for volume work.
 

CWLONGSHOT

Residing in New England
Tis a pity making HP bullets is such a ginormous pain in the behind. Single cavity is bad enough, dealing with that pin, and heat control is just too tedious for volume work.
I was in this camp BEFORE I got my hot plate!!

The key to HP casting is HEAT!! FORGET about low temps. Crank that pot UP! (Ya can crank it down afterwards.)

I cast ALLOT of HP and this is my truth.
CW
 

Rick

Moderator
Staff member
Can't agree with that CW. Your right the key is heat BUT it's not the pot temp that's important it's the mold AND the spud temp that is critical. If your alloy is 700 degrees you are at least 300 degrees over liquidus temp of the alloy, if you can't keep the mold at casting temp with that 300 degrees there are other issues. Cranking up the pot temp much past 725-750 will only serve to burn the tin out of the alloy through oxidation far faster.
 

Spindrift

Well-Known Member
All my HP- moulds are MP, brass moulds. Some 2-cav, some 4-cav. Actually, I don’t think they are so difficult to cast with. The 4-cavity moulds are heavy, though. But after pre-heating, and perhaps 5 pours, they cast well. I have found it is important that the sliding pins attached to the HP pins slide freely, under gravity. This is achieved by not tightening them completely.
 

CWLONGSHOT

Residing in New England
Can't agree with that CW. Your right the key is heat BUT it's not the pot temp that's important it's the mold AND the spud temp that is critical. If your alloy is 700 degrees you are at least 300 degrees over liquidus temp of the alloy, if you can't keep the mold at casting temp with that 300 degrees there are other issues. Cranking up the pot temp much past 725-750 will only serve to burn the tin out of the alloy through oxidation far faster.
Not doubting your experience man. I read and know you know your stuff.

But I stand by what I said. Know, Im not a newb and have been at this long enough to have tried and failed many things about casting this is what works for me. Not that its the only way.
Question asked and answered as to my method.
I shoot them into many materials from water to papers/wet papers to sawdust. I know what my alloys do what & to what diameters they reliably expand. So if Im doing anything to my alloy... I LIKE THE RESULTS!
CW
 

Rick

Moderator
Staff member
It's not a matter of my experience, it is the metallurgy of Sn in Pb. The purpose of putting Sn in the melt is that Sn reduces the surface tension of the lead and allows it to much better fill out the details of the mold. The metallurgy is that Sn cannot do that above 750 degrees. Plus of course the faster oxidation. But hey, if your happy . . .
 

CWLONGSHOT

Residing in New England
It's not a matter of my experience, it is the metallurgy of Sn in Pb. The purpose of putting Sn in the melt is that Sn reduces the surface tension of the lead and allows it to much better fill out the details of the mold. The metallurgy is that Sn cannot do that above 750 degrees. Plus of course the faster oxidation. But hey, if your happy . . .
Again man, not doubting you!! ;) Its all good and again I respect and appreciate what you and everyone brings yo the table. But, all must also realize theres may not the only way! ;)

If ya look, I never did tell ya the temps I run, just that ya need to turn up that temp! I know many casters glue to there PID or thermo and never raise that temp!

CW
 

Rick

Moderator
Staff member
Not arguing with you CW. Simply putting out the info for those that wish to learn, many people read the forum including folks new to casting.
 

CWLONGSHOT

Residing in New England
Not arguing with you CW. Simply putting out the info for those that wish to learn, many people read the forum including folks new to casting.
EXACTLY!
ABSOLUTELY, we aint arguing! We are conversing different points of opinion! Intelligent folks comparing notes.
You have stated irrefutable facts. Ill not doubt them!
My point is as I stated:
HOTTER TEMPS MAKE BETTER EASIER HOLLOW POINT BULLETS!
Your is;
BE CAREFUL WITH HEAT, TOO HOT& YOU WILL LOOSE YOUR TIN!!!
;):p:):):)

CW
 

Rick

Moderator
Staff member
Well that and at a 700 degree pot temp you have roughly 300 degrees over liquidus temp to keep the mold and spud at a good operating temp, far more than is needed. So . . . What will 400 or more degrees get you? ;)