Not Happy with Molds Available – Design your Own

[USSR]

Having 2 brass molds for my 45-70, one of which was made by Accurate Molds, I decided I needed something that would cast about a 300 grain bullet. You see, my Uberti made Winchester 1886 only weighs 7.1 pounds, and from the bench the 345 grain and 405 grain bullets pound me pretty good. Besides, who doesn’t enjoy getting a new brass mold. Since I knew what to expect from Tom at Accurate Molds (top quality/easy casting), I went to his website looking for a .46 caliber bullet in the 300 grain range. Unfortunately, there was nothing there that appealed to me. I starting looking at his .45 caliber molds. His 45-290H mold was exactly what I had in mind. So, I contacted Tom about the possibility of bumping the diameter up on this bullet to .460”. No problem he said, however, since it was to be used in a 45-70 rifle, he suggested a slightly smaller diameter on the front band by pointing out that SAAMI spec’s for the 45-70 has a short throat and needs the smaller diameter. So, that was what the mold specifications were: .460” diameter instead of .452”, and the smaller diameter front band. Had my first casting session today, and am very pleased with the result. Here’s a drawing of the original 45-290H mold.

Don

 

[Joshua]

Nice looking bullet.

It kinda looks like a Lee 457-340-F that had an 1/8” milled off it’s rear.

Josh

 

[Ian]

Except the Lee has a parallel nose and an abrupt step between nose and front band diameters.

Don, what mould number did Tom give the one he cut for you?

 

[USSR]

Ian,

He stamped the mold 45-290H, which was the starting point. Personally, I think it should be called 46-300DK, since it is a 46 caliber bullet and weighs 298 grains.

Don

 

[Ian]

I'm a big fan of lighter bullets in the big-bores. No sense in enduring the punishment of 500+ grain recoil if we aren't shooting 1,000+ yards or slaying buffalo.

 

[Joshua]

So, a few questions. Is the curved front band, more or less acute, as it relates to centering the bullet in the rifling, when compared to the Lee’s straight sides and abrupt front band?

Or, do the Lee’s longer straight sides/bearing surface compensate for it’s lack of gentle transition?

Or, is this one of those, “it depends on how the throat is shaped/every rifle is different and likes different things” situations?

Josh

P.s I still like how it looks!

 

[USSR]

Hi Joshua,

I can't answer your question, so I've asked Tom if he would. Hopefully, he will drop in.

Don

 

[USSR]

Joshua,

Just received an email from Tom saying he is no longer a member of this website, so perhaps one of the guys here will be able to answer your question regarding the curved front band .vs the Lee's long straight sides.

Don

 

[Outpost75]

As FYI I had Tom do 45-290H as a heavy .45 Colt bullet for the Ruger revolvers and the H&R Handi Rifle. I wanted a full-diameter front band north of the crimp groove which fit the cylinder throats. .452 is the maximum tolerance, and by specifying nose tolerance negative the bullet can be pan-lubed without sizing and chambers freely in either rifle or revolver with perfect alignment. I dislike an abrupt step and reduced diameter nose which do not contact the origin of rifling in a rifle chamber. Ideally the ogive of the bullet should be lightly marked by the lands upon chambering, but loaded rounds extracted without firing should not debullet or show evidence of being set back into the case by engraving force. Hope this answers your question.

Larry Gibson fired this pressure test for me in his 10-inch T/C Contender using a strain gage with the Ohler M43 system. 4-5/8 inch revolver velocity is 860 fps, and 20-inch Handi Rifle is 1087 fps with 7.5 grains of Bullseye. Pressure is 17,400 psi, which slightly exceeds SAAMI MAP, but is well within safe design limits for modern Colt and 1873 Winchester clones and the medium-frame Rugers. Bullet weight is 295 grains in 1 to 30 tin-lead from Roto Metals, which is my favored hunting alloy. No issues whatever with leading using 40-60 olive oil/beeswax. Penetration is astounding, accuracy stellar and recoil is very manageable. I see no need for a heavier load.

 

[Ian]

I didn't know about that one or I might not have designed the 45-297G which maintains a strict 1.615" maximum OAL at maximum case length in order to fit and feed in any .45 Colt arm.

My load is a much more conservative 6.2 grains of Bullseye, but the only guidelines I had were some extrapolation of existing data and QuickLoad models. Thanks for sharing Larry's pressure data.

 

[Ian]

The reasoning for my load, it's a little over SAA max pressure of 14KPSI but I'm using modern guns. It appears that the M43 data is in MPa, which equates to 25-26KPSI from the readings. 6.0 grains is just under maximum pressure according to this model with the 297G loaded thusly:

 

[USSR]

As FYI I had Tom do 45-290H as a heavy .45 Colt bullet for the Ruger revolvers and the H&R Handi Rifle.

Thanks for that design, Ed. Reducing that front band from .460" to .457" works out really well for the 45-70.

Don

 

[Joshua]

Thank you for answering my question Ed.

Josh

 

[Ian]

Josh, a visual for you:

 

[Joshua]

OK, let the drift begin.

And, this is why the XCB bullets work so well, by the way there seems to be a whole lot a different mold versions that are associated with the XCB rifles. May be better to call it a family of bullets.

I’ve searched for a picture/drawing of the MP 30 silhouette and haven’t found one. It also fills that same throat gap well, doesn’t it?

I recently bought an NOE 316-155 FN from Brad, that I hope to push harder (up to 2300fps) in my Arisakas. I believe that it was part of a group buy that was based on this drawing, they were available in .311”, .314”, and .316”.
Hopefully that long taper before the crimp groove will allow it to center up and be supported well in the throat. In this drawing it still however jumps from .308 to .311 when it hits the first driving band.

Well I’m gonna go cast some right now. Also have a Lee .312-155 six banger I’m gonna break in.

Josh

 

[Ian]

The "XCB" bullet is as old as time, we just revisited the matching taper thing one more time, or several actually. The original .30 XCB bullet was designed by yours truly and is cataloged as Accurate 31-190X. Someone else designed the pre-NOE bullet at Accurate, I forget the number but it's still there. He wanted more point and collaborated with some other people to add other ideas to it and the NOE version was born. It doesn't work very well, actually. The NOE 310-165 has a lot of things wrong with it but it does pretty well in the .308 Winchester precisely because it does NOT match the throat. It fits in the correct places though, and steers straight while absorbing the engraving pressure incrementally instead of all at once as the matching taper designs do, this reduces riveting stress on the base of the bullet as well as sideways distortion during the launch. The NOE bullet needs a tougher alloy to work well, whereas other designs with a self-aligning nose which give support in the right places and wiggle room where it's needed (not just a single, straight taper) tend to work with a larger spectrum of alloy at high velocity.

You will not find a drawing of Bob Kell's .30 Silhouette design anywhere. He will not release it. Best you can do is acquire a mould from MP Molds and measure castings if you're curious, or just shoot them and be happy.

I have one of those NOE molds in .311, it casts .313 on the body and .302x.304 on the nose with straight wheelweights which makes it pretty much useless for anything except a wallowed-out SKS or AK. If it were cut to the drawing it would be better, but he jump in diameter is very much a problem and an oversight (or just pure lack of understanding) of the designer.

Ed Harris designed the Lee 312-155 for the Soviet round and it is a fantastic bullet in many things .30 and .31 caliber. It has a concave taper to the nose, subtle yet effective. Lee puts too little gas check shank on some of them (they vary by whoever sets up the machine that day) but still work very well. I look forward to a report on how yours turn out from this casting session.

Fiver and JT re-worked the original Ed Harris design and cut some moulds very close to Ed's (closer than Lee is making them now) but sadly that venture died on the vine. I would like to make some tweaks to the .30 Silhouette for the purpose of powder-coating and may end up just grinding my own cherry and making it myself since it is beyond the capabilities of Mountain Molds and Accurate Molds to do and NOE can't ever make a mould cast the size specified.

 

[fiver]

to tell the Truth we got Ed's actual original drawings for that one.
very, very minimal changes were made to the design.

I still slap myself for not dibsing a mold before taking off to work for 5 weeks straight and missing the whole mold cutting thing.
it's not like it would have taken any more effort than a phone call or an e-mail to get one.