Bullet making pics.

I am very happy to see that thread back to life. Thanks to all.

Unfortunately, I am still unable to reach all the other threads I bookmarked a few years ago before I started in bullet making. Never got any answer from Elmer about the new platform search function failing to find any, despite I have the very exact thread title in the bookmark. PITA.


On my own very little experience, I was never able to understand that search/quest for "stretching" the jacket at core seat.

Just at the moment it get seated in place, the core is secured to the jacket by banding / shrink fit. I mean the Op expands the jacket to the tool diameter using the lead flow pressure, then once the punch pressure get released, the freshly seated jacket want to "spring back" and so tightly hold the core into its tiny muscular arms.

In my mind, stretching the jacket means lowering it's section around the core, so less effort from the jacket onto the core. Not a good direction to go.

Stretching the jacket means the Op has overtake the stroke needed to fully achieve THE maximum possible core / jacket / (die) diameter expansion // VOLUME // in between the core seating punch and the reciprocating punch/ejector.
 
dwconder said:
but more pressure you place on jacket you I think need to stop before it stretches I see no loss in accuracy let me know what you think you need to mic your dia. as you pressure your jacket the die will only make what the id of the die is.
Click to expand...

I remember reading here some cracked core seating die horror stories .....
 
Every one has a different method of seating cores. Hottenstein and Bart 2 of tue best in the business both seat cores differently. Figure out what works best for you. I don't believe you can over seat a core. If you do it'll pop the jacket. Back off a half a turn and go to seating. Personally I like to seat right to the point before you see thr frost line. That's a faint line around the seated core appearing on the jacket. The weak spot. That's how I was taught and it works for me.
 
Sleepy Hollow said:
Every one has a different method of seating cores. Hottenstein and Bart 2 of tue best in the business both seat cores differently. Figure out what works best for you. I don't believe you can over seat a core. If you do it'll pop the jacket. Back off a half a turn and go to seating. Personally I like to seat right to the point before you see thr frost line. That's a faint line around the seated core appearing on the jacket. The weak spot. That's how I was taught and it works for me.
Click to expand...
Randy Robinett mentored me when I started bullet making and continues to do so to this day. Once you have a basic seating pressure established, it's good to experiment and start your own learning curve with your dies.
 
Dave Coots said:
My question is, if the jacket is not stretched a little, how do you know the core is fully seated in the base?
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Dave, Bart told me he seats core til the jacket grows 0.001 in diameter. So to 243.1
Kenny taught me to seat my jackets til that little frost line appears at the top of the core. Then back off a quarter turn or so. Kenny way seems to work for me. My jackets grow about 0.003. My bullets are 67 gr on .83l25 jackets. Lead line measures out to be 64-65% and they shoot sweet
 
Liseo said:
This parameter is for boat tail and flat base bullets?
Click to expand...

Boat tail for me.

Sleepy Hollow said:
Dave, Bart told me he seats core til the jacket grows 0.001 in diameter. So to 243.1
Kenny taught me to seat my jackets til that little frost line appears at the top of the core. Then back off a quarter turn or so. Kenny way seems to work for me. My jackets grow about 0.003. My bullets are 67 gr on .83l25 jackets. Lead line measures out to be 64-65% and they shoot sweet
Click to expand...

Robert

The dimension Bart spoke about is at the base?
 
OliveOil said:
I am very happy to see that thread back to life. Thanks to all.

Unfortunately, I am still unable to reach all the other threads I bookmarked a few years ago before I started in bullet making. Never got any answer from Elmer about the new platform search function failing to find any, despite I have the very exact thread title in the bookmark. PITA.


On my own very little experience, I was never able to understand that search/quest for "stretching" the jacket at core seat.

Just at the moment it get seated in place, the core is secured to the jacket by banding / shrink fit. I mean the Op expands the jacket to the tool diameter using the lead flow pressure, then once the punch pressure get released, the freshly seated jacket want to "spring back" and so tightly hold the core into its tiny muscular arms.

In my mind, stretching the jacket means lowering it's section around the core, so less effort from the jacket onto the core. Not a good direction to go.

Stretching the jacket means the Op has overtake the stroke needed to fully achieve THE maximum possible core / jacket / (die) diameter expansion // VOLUME // in between the core seating punch and the reciprocating punch/ejector.
Click to expand...
OliveOil, while these are valid considerations, the lengthening of the jacket occurs only at the core-face : jacket-wall junction - the result of the core bleed-by initiating a "pinch". We are exceeding neither the tensile strength, nor, the elastic limit of the gilding metal. As noted by Dave Coots, a visible and uniform bleed-by assures complete evacuation of air - monitoring length, as core-seating pressure is applied, is a good method, which avails consistently uniform results.

Measure a handful of raw jackets, recording their lengths and place them [sequentially] into your blocks, drop cores and proceed seating. The jackets, as the base forms, will continue to shorten (lack of pressure will allow cored jacket to stick on the punch). Continue adding pressure until
having reached the shortest average, subsequent cored jackets begin lengthening by about 0.002" - 0.003". They'll all release from the punch (presuming a good punch fit) and should have uniform diameters. Per previous posts, lube and dies - especially tool steel vs. carbide - may make for differences. You will figure out what your dies "want"!

The individual from whom I purchased my Rorschach .224 die-set instructed me to, "apply pressure until the jackets are pinched off, then back off 1/8 to 1/4 turn . . ." I deemed THAT a little excessive (worried that I may BREAK the die - AND didn't/don't like that [accompanying] LOUD crack!).
I devised a somewhat different methodology: measuring both diameter AND length.

There are, as stated above, many ways to, "skin this cat"! ;) Experimentation is golden! Maintain records - over time, those will point the direction to turn with the next jacket LOT . . . o_O RG
 
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R.G. Robinett said:
OliveOil, while these are valid considerations, the lengthening of the jacket occurs only at the core-face : jacket-wall junction - the result of the core bleed-by initiating a "pinch". We are exceeding neither the tensile strength, nor, the elastic limit of the gilding metal. As noted by Dave Coots, a visible and uniform bleed-by assures complete evacuation of air - monitoring length, as core-seating pressure is applied, is a good method, which avails consistently uniform results.

Measure a handful of raw jackets, recording their lengths and place them [sequentially] into your blocks, drop cores and proceed seating. The jackets, as the base forms, will continue to shorten (lack of pressure will allow cored jacket to stick on the punch). Continue adding pressure until
having reached the shortest average, subsequent cored jackets begin lengthening by about 0.002" - 0.003". They'll all release from the punch (presuming a good punch fit) and should have uniform diameters. Per previous posts, lube and dies - especially tool steel vs. carbide - and lube may make for differences. You will figure out what your dies "want"!

The individual from whom I purchased my Rorscach .224 die-set instructed me to, "apply pressure until the jackets are pinched off, then back off 1/8 to 1/4 turn . . ." I deemed THAT a little excessive (worried that I may BREAK the die - AND didn't/don't like that [accompanying] LOUD crack!).
I devised a somewhat different methodology: measuring both diameter AND length.

There are, as stated above, many ways to, "skin this cat"! ;) Experimentation is golden! Maintain records - over time, those will point the direction to turn with the next jacket LOT . . . o_O RG
Click to expand...

Thanks RG, your words are gold, as usual.
..... And copied to my personal database before the damned thread vanished again !!! :D
 
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