Anyone use Blackmon's boat tail die?

[ohnomrbillk]

I have a Blackmon 224 7s Swage set.

My my work hours haven't been conducive for phone calls for normal sleepers, and I haven't had much luck getting an email response.

I have the 4th die for boat tails. It looks like you maybe use the die and internal punch as an alternative core seat, and then the external punch it included is used for point form.

Is that correct?

[just bill]

I have the .308, it has 2 punches. 1 one for the punch holder which forces the core into the die to seat, expand the core and jacket and forms the boat tail in the base of the die with the base punch. The boat tail is finished in the point forming die.
Bill

[Smokin7mm]

That sounds correct. I do not have blackmon dies, but my RCE dies are set up that way and that is the way they work. The boattail die is used in the core seating and forms the boattail. Then the external punch that has the recess for the boattail is used in the point forming.

Bret

[ohnomrbillk]

Thank you

Do you measure the OD of the jacket after core seat to determine how far the punch goes into the die?

[just bill]

Thank you

Do you measure the OD of the jacket after core seat to determine how far the punch goes into the die?

You have my curiosity as to why you would have to measure the jacket diameter after seating the core?

[ohnomrbillk]

You have my curiosity as to why you would have to measure the jacket diameter after seating the core?

Right or wrong, the old timer that first introduced me to the Swage process would use a micrometer to measure the diameter of the jacket after the core was seated to adjust punch depth. At some point, despite lowering the punch more, it does not expand any bigger. The lease amount of punch entering the die that results in the target diameter is his idea of perfect punch adjustment.

How ie do you know how far to adjust the punch?

[just bill]

Never thought about it that way. I can see how that would prevent the boattail from bulging. Interesting.
Bill

[Smokin7mm]

Final bullet diameter is achieved in the point form die. After seating a core it should measure just under final diameter. If you are talking adjusting the core seating punch, I do it mostly by feel. I do measure to make sure it is bumping up properly but if you use too much pressure you can separate the jacket. Also on commercial jackets that are tapered you need to select the punch that is the best fit for the amount of seated lead. Too small and you will get bleed by. Too large and it will start to cut the jacket leading to separation of the jacket.

Bret

[aaronraad]

Right or wrong, the old timer that first introduced me to the Swage process would use a micrometer to measure the diameter of the jacket after the core was seated to adjust punch depth. At some point, despite lowering the punch more, it does not expand any bigger. The lease amount of punch entering the die that results in the target diameter is his idea of perfect punch adjustment.

How ie do you know how far to adjust the punch?

I agree..."least amount of pressure"

Does your core seated jacket measure the same OD (+/-0.00010") across the base compared to the punch lead line?

A repeatable core seated jacket diameter means you are more likely to produce repeatable point forming diameters...until the point form die wears to a 'significant' amount, not surprisingly at the start of the ogive.

Stopping <8° boat-tails from collapsing to under the shank/ogive diameter during the point forming step is a fun game to try. :violin: