Undersize Lyman Postells --- except for driving band

[mehavey]

Brand new mold arrived today.

Anyone else had this happen...?

http://i47.tinypic.com/fwu3dl.jpg
I could understand (though not like) all the bands being undersized, but just the forward ones?

[geargnasher]

I have two of them, both made in the past few years, that cast about .4555" x .45655" with 20:1. Base band is small, too, though. Send it back to Lyman if it won't cast a round, .457" with 20:1 at least.

Next time buy a different brand, preferably a custom maker who still cares about what alloy you use and what size you want your boolits. I highly recommend Accurate Molds, and since they don't do group buys they aren't years behind in production like most of the others.

Gear

[runfiverun]

well they are improving..
1 outta 5 is a step up from normal.

[Larry Gibson]

Before you "send it back" check the Lyman #3 or#4 cast bullet manuls and see what the alloy was that they based the nominal .457 on. I don't think itwas a 30-1 alloy.

Also are you using the same castin technique with a dipper as shown i the Lyman manuals? Using a bottom pour, or just pouring into the mould can easily cause undersize bullets, especially with larger bullets such as yours.

Larry Gibson

[mehavey]

Casting technique has been/remains a full dipper held in tight contact w/ the sprue hole for a lazy three-count, then released slightly to put a liquid "dollup" on it to harden. ('Has been a dependable technique for sharp fill-out/clean bases since`68 when I figured out bottom-pour was always a frustrating [dice] shoot..)

As originally noted, I could understand all bands being undersized, ...but different sizes like that? `Tis a puzzlement.

I'll shoot it ahead of 75gr 1F tomorrow and see if there's a pony in that pile.

Meanwhile, I've also got a Paul Jones 540 Creedmore on order.
http://www.pauljonesmoulds.com/45001.jpg
...and can always shoot some more of Dave Jennings' superb Postells in the meantime.

But still... `tis that puzzlement. [smilie=b:

[Idaho Sharpshooter]

now you know why most of the BPCR guys have gone to Jones or Brooks, and a few to Mr Gullo.

Maybe this is Lyman's new bore riding groove design...?

Rich
Sua Sponte

[John Boy]

... and see what the alloy was that they based the nominal .457 on. My understanding is their CAD program calculations are based on Lyman #2 alloy

[geargnasher]

My understanding is their CAD program calculations are based on Lyman #2 alloy

Lyman load data has been based on #2 and 20:1 both.

Gear

[44man]

Pretty common with Lyman and RCBS. Hard to get the right size.

[mehavey]

100 Yrd Results this evening:

http://i49.tinypic.com/2vvj7lg.jpg

http://i45.tinypic.com/30cops4.jpg

I dunno, guys.
This is a tough call.

:groner:

[Larry Gibson]

Hmmmm.....459 and excellent accuracy when cast of 20-1, the alloy it was designed for........don't "send it back"...send it to me:D

Larry Gibson

[9.3X62AL]

Maybe this is Lyman's new bore riding groove design...?

OUCH!

Even at nominal .457" diameter, how many (more like, HOW FEW) 45 caliber rifle bores are well-served by a .457" casting? The three 45-70 rifles I've owned (2 Marlins and a Ruger #1) have/had throats mic'ed at .459"-.461". A beater Trapdoor now in the safe has grooves running .462".

I "get it" that lead/tin alloys can "bump up" boolit diameters more readily than can smokeless fuels, but what's the point of relying on such gymnastics when a mould can be cut to fit well as easily as it can be cut undersized? THAT I don't get, at all.

[mehavey]

Hmmmm.....459 and excellent accuracy when cast of 20-1,
the alloy it was designed for........don't "send it back"...
send it to me

Unfortunately (or fortunately) that was Dave Jennings' Lyman 457132/Postell from Montana Bullet Works
-- not the offending Lyman mould that I received a few days ago. :(

Somehow, I don't think going from 1:30 to 1:20 is going to solve a 4 thousandths difference between that one
driving band and all four other bands. But...... I've gone ahead and ordered up some #2 from RotoMetals "...just to see." [smilie=1:

[Larry Gibson]

You might just try it anyway with 20-1. Also I might suggest not; "dipper held in tight contact w/ the sprue hole for a lazy three-count" but instead as soon as the cavity is full rotate back to sprue at top while the alloy is still molten and then "put a liquid "dollup" on it to harden." I hold the mould over the pot when doing such and let most of the full Lyan dipper of alloy flow into and over the sprue hole and plate.

.457 is the nominal diameter for the Lyman mould anyway. So .002 shouldn't be hard to pick up....possibly more. If the mould doesn't work out I would really like to see that mould before you send it back to Lyman(?). I will pay the shipping.

Larry Gibson

[btroj]

Wow Larry, are you a customer service rep for Lyman?

I would never buy a Lyman mould for 45-70 unless my rifle was of .457 bore or smaller. I can get a mould from other makers that will cast the size I need without playing games with technique, temp, alloy and stuff. I want a mould that works, first time, every time.

[montana_charlie]

I don't remember where I read this, but it was from Lyman and it was a long time ago.

The .457xxx designation means that a bullet cast from that mould, in Lyman #2 alloy, can be sized down to .457" without damage ... 'damage' defined as 'noticeably modifying the original design'.

While .457" may be a minimum acceptable diameter on the small end of the Lyman tolerance range, the wording of the above indicates that a bullet larger than .457" is expected.

CM

[Larry Gibson]

Wow Larry, are you a customer service rep for Lyman?

I would never buy a Lyman mould for 45-70 unless my rifle was of .457 bore or smaller. I can get a mould from other makers that will cast the size I need without playing games with technique, temp, alloy and stuff. I want a mould that works, first time, every time.

No I'm not. However, like a few I don't set out to bad mouth the companies that have made our hobby/sport/avocation possible. A mould is simply a product that is mass produced. I seen defects in all of them. Even a very recent GB mould was "defective" for cast oversized bullets. The maker made it good. Point is nothing manmade is perfect. I've had 2 other GB moulds that cast grossly oversized with the alloy I wanted to use but I do not blame the maker as that was not the alloy the moulds were designed around. There are + and - tolerences on anything produced. If any makers mould only casts to nominal diameter it should not be considered defective. If you want a bullet over the nominal diameter it is best to get one from a custom maker who can guarentee that oversize diameter.

To "expect" a mould cast over sized is not a realistic expectation in my estimation. To criticise a mould because it does not cast to nominal when we don't use the right alloy the mould was designed for or because we don't cast correctly is also unrealistic in my estimation. I think we see to many moulds criticised (all makes) for the casters error.

I've had numerous moulds sent to me that supposedly cast undersize. None did when I used the right alloy and casting technique including a recent Lyman 454190 from a prominant forum member. Yes, there are defective moulds shipped by all the makers. The more new moulds you buy the more likely you might get one. Most of them stand by their products. However, before criticising the mould for being oversize or undersize make sure YOU are casting correctly and are using the right alloy.

Now, please, don't anyone get their feathers ruffled. I've made mistakes, I've not used the right aloy, I've even not cast correctly for the bullet/mould used and got poor bullets. Happens to all of us. If the mould is defective then so be it and I'm sure Lyman willmake it right. However, if it's not defective simply because it's not casting the size of bullet we want then lets not criticise the makers is all I'm saying.

Larry Gibson

[Cap'n Morgan]

I did several custom molds for 45 cal "money" type boolits. From what I've found, you should expect a shrinkage of approx 0.7% from a 20:1 alloy - a little more with less tin in the alloy.

If you have the right measuring equipment - or know somebody who has, you can measure the mold and calculate the ideal dropping size from that specific mold:

To find the bullet diameter from a known mold size, you just divide the cavity hole size with 1.007 (Notice the two zeroes)

To find the mold size for a given boolit diameter, multiply the diameter with 1.007 That is, for a mold to cast a .459 boolit, the cavity should measure .459x1.007=.462

[25ring]

Have you tried casting at a hotter temp? Just a thought.--Mike.

[John Boy]

mehavey, here is the Lyman Postell, 459, cast as is with clip on WW's (Bhn15.4) and 1/2% SN shot with BP that you might want to try...

100yds - 25 shots - 14 in the ragged hole -

http://i222.photobucket.com/albums/dd220/Meadowmucker/Targets/PDRM2558.jpg

[mehavey]

Got some #2 coming from RotoMetals

I'll tray that, and also the traditional WW and a "dash' of tin as you suggest. That was pretty much what I shot out of the
Smith for years in the N-SSA (and everything I shot when starting back in the dark kerosene days)

It's only lately in the last 15 years that I've tried to get fancy. :violin:

[mehavey]

Got some #2 coming from RotoMetals

I'll try that, and then also the traditional WW and a "dash' of tin as you suggest. That was pretty much what I shot out of the
Smith for years in the N-SSA (and everything I shot when starting back in the dark kerosene days) If the Lyman mould
will shoot w/ harder alloy, I'll keep it. if not, I'll see if the `85Marlin will eat it.

It's only lately in the last 15 years that I've tried to get fancy. :violin: