Core seating ???

Bro.D

Member
Need some help on core seating. My problem is this; While core seating, things will be going along just fine, then I will have maybe four or five in a row that will not let go of the punch. I get them off by cycling the press again. So is it an issue of just not quite enough pressure...am I running on the ragged edge of not enough seating pressure or could there be other issues? The core punch only shows, in my opinion, small amounts of lead buildup. More of a film than build up. I don't think the jacket is sticking because of lead on the punch. What else could it be?
Here is the second half of the question. For those that I had to cycle twice, would you use them in a match or would you cull them and use them for P-dogs or informal shooting? As best as I can measure they are identical to the jackets that come off with only one cycle. Will having to cycle them twice show up on the target? (100-200 BR) Thanks, Bro.D
 
Bro D Sound;s to me that the core seating punch is to small,you dont want any build up on it.The ones you made that you had to recycle through the press i would just use them for fireforming.kenny
 
Core seating

I think your on the edge. did you mike the diameter of the cored jacket?.
I think you may need a tad more core pressure. Easy does It.
Check inside of the cored jacket for bleed backwith a magnifying glass. there should be none.
If yo have bleed back your punch is to small. Sometime just a few 1/10000.
Be careful of lead build up on your punch . There should be none.
You need just enough pressure to make the jacket stick to the die walls.
i hope this helps.
 
Bro D

As a "former" bullet maker, I must say that you are looking forward to the happiest day of your life.:D..........jackie
 
Bro.D

Is it a new bucket of jackets?
I have had jackets ordered at different times that take different punches for the same weight bullet.
How much lube, over lubing causes jackets to pull out with the punch especially if the punch is too small with too much pressure or too large and contacting side wall of the jacket.
The leading on the punch can be taken care of by polishing with some 1000 grit paper and Flitz; I do this on all my punches.
Do you have the means to make your own punches?
If you do have the means make several in .0005 increments, I have made many now for my own use and a friends, very simple.
The punch used needs to have some clearance to the sidewall of the jacket, not much but some; if it scrapes the jacket wall you take a chance of trapping air and loose core adhesion.
Keep detailed records of what and how you do things, weigh lube xx grains per xxxx jackets, tumbled for xx minutes, clean and wash with ??, etc…. This is very important and especially if you do not have someone to guide you.
You only want enough pressure to expand the core into the jacket and push it to the walls of the core seat die, mic this dimension and record it. Increase the seating pressure until the dimension doesn’t change then back it off a little. Most make the mistake of over seating the core, I did in the beginning.
Are your dies carbide or steel? This makes a difference in the amount of lube used.

And the list goes on, just some things to consider. I was asked this question when I started making my own, are you making bullets to save money or to make a better/ more consistent bullet and was told that if you are making bullets to save money you had better by them. The guys that make BR bullets for a living in my opinion deserves every penny they get; it is a laborious, boring job.

Rick
 
So Jackie was that the day you stopped making your own bullets.;)
 
core seating

while your core seating try wiping the core punch with your fingers before placing core on see what that does
 
Here is what I'm going to do.

This is a new batch of jackets. The last batch worked perfectly with the equip. I have. And since I am somewhat new to this art/voodoo thing called bullet making I only have a few punches. On this new batch my .2104 punch is a little too loose. I feel sure this is why things are happening the way they are happening. .2108 scratches the inside wall of the jacket. Thus, it looks like I need a few more punches to fill in the gaps. I'm thinking a .2106 will be the deal. I will try the new punches first and then if that doesn't fix it I'll drop the lube down a bit. Thanks for all the help. Bro.D
 
Core seating

That depends on who made your dies.
Last i knew it was $35 to $50 per punch.
Simonson charged $35 that was a while ago.
Check with david detsch at diemaker.us
 
On this new batch my .2104 punch is a little too loose. I feel sure this is why things are happening the way they are happening. .2108 scratches the inside wall of the jacket. Thus, it looks like I need a few more punches to fill in the gaps. I'm thinking a .2106 will be the deal. Bro.D

I would work with core seating pressure before doing anything else. -Al
 
I have this same thing happen occasionally. If the core seating pressure seems to be right, don't change it. What I do is start the jacket back up into core seating die. DO NOT cycle completely. Just go in length of jacket, then back out. This will 99.9% of the time pull the jacket off the punch.

JimP
 
Bro D Heres somthing else you can try if your not selling bullets.You can make the cores fit to the punches you have.Say your making 68 gr try 67,if you go with the 67 say you will have to make new cores.if you go with a 66you could just squirt the ones down that you have.Kenny
 
Jackets inside are unique to lot...

Bro D Heres somthing else you can try if your not selling bullets.You can make the cores fit to the punches you have.Say your making 68 gr try 67,if you go with the 67 say you will have to make new cores.if you go with a 66you could just squirt the ones down that you have.Kenny

Good info here...........

Still your gonna have to get ya a "series" of punches rangeing .010 for a 66-68gr. weight range of bullets.... If ya want to go with a full 10gr of bullet weights (60-70gr) AND jacket lengths (.790 and .825) you will need a pretty large supply of core seat punches to accomidate. Say 20-25 .001 increments.

Most don't know or understand the "core seat punch issue" when they want to dive off into bullet making...

Another route.....
Call up Eric Stecker at Berger/J4 and buy by case/lots so that the bullets/weight your making WILL "mate" to your current punches.
case of J4 is 8000 .790 jackets and 7600 of .825 jackets.

Explanation:
When I say..."WILL "mate" to your current punches".
I mean you will take a known jacket (have alot of a one lot of jackets ) and make a weight range of lead cores and experiment till the punch FIT's the seated core height to internal jacket diam.. EXACTLY. No scrape and absolutely min or no lead bleed by... Now, you'll be set to make a bunch of mirror image bullets with a known set-up and final end results.
IMOP... A 6mm 14 twist rate, your ok with a .790 jacket bullet of 58gr - 65gr weight... Now the .825 jacket IMOP is at it's best in a 14 twist barrel in a weight range of 65-66gr. I'd recommend a 13-13.5 twist for the 68=> and a .825 jacket........ But a bunch of select HOF shooters got there with .825's @ 68gr in 1-14" barrels...........;)


This should set ya up for years of shooting till your punch increase in number and diversity.

good luck and make GREAT bullets!,
cale
 
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