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Forester
01-07-2008, 11:53 PM
Ok, this may be a dumb question, probably is actually but I am confused--happens easily...

On a boolit with 3 or 4 drive bands should all bands be full diameter? If so, what would cause a mold to cast boolits with narrower drive bands as you move forward, aside from manufacturing mistakes? I am seeing this in an RCBS mold and a Hoch nose pour, most notably in the Hoch.


Edited to add: I just noticed that under my name it now says "Boolit Master" this simply can not be, every day I come to this forum I realize I know nearly nothing about casting!

IcerUSA
01-08-2008, 01:10 AM
That just relates to the amount of posts here as nobody knows it all . :)

Some of the moulds are made with the forward bands smaller , less resistance to ingraveing I beleave and/or to help with allinement with the bore , I'm sure someone with more knowlage will jump in here and give a better answer than me .

Keith

Buckshot
01-08-2008, 01:12 AM
Edited to add: I just noticed that under my name it now says "Boolit Master" this simply can not be, every day I come to this forum I realize I know nearly nothing about casting!

...............The fact that you're even miking your cast boolits shows enough interest and involvement for you to be a "Boolit Master".

Your boolits may have tapered drive bands due to mould design. I don't know which RCBS designs might be, or Hoch for that matter but Saeco offers some tapered designs as does Raphine. I'd bet money the Hoch os designed as a tapered slug and I'd be curious to know what RCBS mould you're using.

..............Buckshot

floodgate
01-08-2008, 02:05 AM
Forester:

Those "tapered" bullet designs were popular back in the Schuetzen era of the late 1800s - early 1900s, and were also tried with more modern rifles in the 1920s - 1930s. They were either seated directly into the barrel throat, followed by a powder-charged and primed case, or were just started by hand into the case and carefully single-loaded by hand. More recent experimenters have also designed them to fit special chamber throats.

floodgate

Forester
01-08-2008, 10:07 AM
...............The fact that you're even miking your cast boolits shows enough interest and involvement for you to be a "Boolit Master".

Your boolits may have tapered drive bands due to mould design. I don't know which RCBS designs might be, or Hoch for that matter but Saeco offers some tapered designs as does Raphine. I'd bet money the Hoch os designed as a tapered slug and I'd be curious to know what RCBS mould you're using.

..............Buckshot

I put a mic to just about everything.

The RCBS is the 45-300FNGC. I don't have it in front of me but the Hoch is a 45-420gr FNGC if I recall correctly.

The gas checks are also a little loose on the Hoch boolit so I am going to try annealing some checks tonight and see how they work.

leftiye
01-08-2008, 07:12 PM
It's a gauge of how well you resist the temptation to open yer yap! Guess I'm not doing too well?

Forester
01-08-2008, 07:36 PM
More details on the Hoch mold:

Rear drive band : .459"

Next: .458-.459"

Next: .457

Next: .455

Is a boolit like this at all likely to shoot well in a recent manufacture Marlin 1895 or am I [smilie=b:

I cast a few today with a new RCBS 405gr FNGC Santa brought me. When I got good boolits they look great, nice and round, all drive bands mic at .459" The mold seems very picky though,,it seems to like the alloy around 810* (too hot for nice shiney boolits :( ) and to cast very, very, very slow...if the mold heats up much at all the boolits go to junk. Had a high reject rate because of small holes in the boolit in the lube grooves.

Buckshot
01-09-2008, 01:52 AM
More details on the Hoch mold:

Rear drive band : .459"

Next: .458-.459"

Next: .457

Next: .455

Is a boolit like this at all likely to shoot well in a recent manufacture Marlin 1895 or am I [smilie=b:

The Hoch sounds like it's measurements are right on for a tapered slug. I don't think the RCBS 45-300 is suppsed to be a tapered design.

I cast a few today with a new RCBS 405gr FNGC Santa brought me. When I got good boolits they look great, nice and round, all drive bands mic at .459" The mold seems very picky though,,it seems to like the alloy around 810* (too hot for nice shiney boolits :( ) and to cast very, very, very slow...if the mold heats up much at all the boolits go to junk. Had a high reject rate because of small holes in the boolit in the lube grooves.

Get a shallow dish and then place a folded cotton face cloth or rag (needs to be cotton) in it and then fill with enough water so the cloth acts like a wick and remains damp. After dumping the slugs and on the way back to the pot to refill set the base of the blocks on the pad. Just say "1, 2, 3," to time while the blocks sit on the pad, and then refill. Modify the time as needed.

..................Buckshot