Swiss GP90 mold.

jordanka16

Active Member
I think this is pretty darn close. I think the slightly shorter length is due to the lack of an iron cap and hollow base, a smaller meplat would be nice as well.

Otherwise if I could get a drawing I could have accurate molds cut a hollow base nose pour and then have erik make the base pin for it.

 
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Ian

Notorious member
Draw up exactly what you want to duplicate the original patched bullet exactly, but with a .180" flat point. Contact Tom via his email at Accurate Molds dot com and ask him to cut you a nose-pour, hollow base mould to your specifications. Once you get the mould, send it to Erik Ohlen at Hollowpoint Mold service dot com and have him make you the required pin. Easier and cheaper to do single-cavity and traditional, knobbed spud. Then you can paper patch the thing and duplicate OEM ammunition.

Personally, I think you'll have better luck just slinging a .31-caliber, gas-checked torpedo through there or doing like Bill mentioned earlier with extra-long-necked brass to get the bullet closer to the ball seat, but you never know until you try.
 

jordanka16

Active Member
I think to do it right I will need to source an original bullet, to get good measurements and also measure the hollow base, get it as close as possible minus the round nose.

And in the meantime try out what you suggested, with the really long .315 or so gas checked bullet. I have dies and brass on the way so I'll just need to figure out a suitable mold, the 314299 doesn't look too bad. Thanks guys!
 

fiver

Well-Known Member
the 299 is a good design.
the problem is in Lyman's execution recently.
you might be getting a 314299 at 314X304 or a 309 body with 299 on the nose.
the latter seems much more common these days.
 

Joshua

Taco Aficionado/Salish Sea Pirate/Part-Time Dragon
Brad is selling a NOE 311299 four banger. Looks like it is still available. A layer or two of PC would get you up to .315”.


Josh
 

Ian

Notorious member
Even with that stupid skinny base band (result of trying to make a plain based and gas check design from the same drawing) that bullet has made some true bughole groups on many occasions from my Throatus Colossum 336. Marlin has used two distinct throats in their rifles, a SAAMI one which steps at the case mouth and has basically a chamfer to the rifling, and the one where the neck diameter keeps on going for another quarter inch and then sorta flows down to bore diameter (it could accommodate a heeled bullet easily).
 

fiver

Well-Known Member
the key is the nose shape closer to the drive bands.
it is the interference fit that lines everything up on the other side.
 

jordanka16

Active Member
Excellent I think I'll try that one out, it's a good multipurpose mold I can use in my .30-30 as well, which is actually a marlin 336. I think I'll leave it at .311 for that purpose
 
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Bill

Active Member
The downside to shooting a regular 30 cal bullet in the 54.5 mm case is that the necks will be .323 each time each time you fire it, then you will have to squeeze them back down to .308 which works the brass a bunch

Bill