RCBS .45-300 FNGC problems

[W.R.Buchanan]

Here's a story!

I recently sent a .45-300FNGC mould back to RCBS for rework. It was dropping bullets that were .4588 to .4592 measured on both axis'. Obviously these bullets would not completely size in a .459 die.

End result is that they went thru the target sideways at 50 ft.

I wrote RCBS a detailed letter explaining what was wrong with the mould and what I wanted done to it to make it right. I basically wanted the driving bands recut to drop bullets cast from WW material at .461-462, so I could size to .460 to accomidate my .4588 groove dia.

A week later here comes the mould with a QC report stating that "this mould was sized perfectly to drop and size to .458". and "Deemed Ideal" for this size bullet.

***!, did you not read the letter?

I wrote RCBS QC and General Manager a SCATHING Letter back,,,, and I mean Burn Your Eyebrows OFF,,, Scathing,,,, indicating that I had some idea of what I was talking about, and that I had already deemed the mould NOT ideal by virtue of the sideways thing, and that was why I sent it back to them in the first place! I wasn't looking for second opinion.

Also the spud that the gas check crimps on was too small and they just fell off. So this mould was definately about .001-.002 too small, and most assuredly not "Ideal"

I got a call back from the new General Manager a few days later, and we talked about this issue for about 45 minutes. He is well aware of Cast Bootits :castmine: He was eager to please me and totally willing to make changes that were positive in their process. It was a productive discussion, and should result in some postive change.

I informed him that nobody uses linotype for common boolits, and that they needed to look at using Wheel Weight material like everyone else does. This would result in larger cherries being used, and since they make all of their own cherries in house, it will not be a big disruption to production to make a cherry that is .002 -.003 larger than what they are doing now. Incidentially a cherry lasts thru about 45 mould blocks before it is trash, so this is even less of a burden to their process than I had previously thought it might be.

I found out that ALL RCBS moulds had been originally spec'd out dimensionally using linotype material for the shrink rate. They are now looking at changing this idea as linotype is not the normal material used by the majority of bullet casters. Besides Lyman uses Wheel Weights for their moulds, and they are RCBS's direct competetor for this level of tooling.

We talked about different methods of cutting the cavities including Circular Interpolation and how they could integrate this into their process. He was aware of Mihecs method but they hadn't been able to make it work, so I suggested some points on cutter design and process sequence that they are trying.

Also we discussed in depth their altering of the sizing of their mould cavities to drop bigger bullets that can be sized down to accomidate different groove diameters. He was not aware that there was so much variation in the industry on bore dimiensions, and especially on the .44 caliber barrels..

They are making me a new .45-300FNGC mould that drops Boolits at .461-.462
and I will relate how it works, what size boolits it drops, and everything else about this project as soon as it comes to pass.

Randy

[doghawg]

I have that mold and am completely satisfied with it. Mine drop at .4585" with ww's. They advertise the mold at .458".

And...if your bullets are going sideways at 50' it sure as heck isn't because the bullets are off by four ten-thousandths.

[PacMan]

I would say that the bullet turning sideways at 50 yards has little to do with the bullet being .002 under size on one axis before sizing.
I would hazard a quess that twist rate and velocity had more to do with it than the .002 along with other things that may be off.
What gun was you shooting the bullet in and at what velocity?

[Piedmont]

Is it smarter to spec. them for wheel weights when they are on the way out? I think they make them small so they will chamber in any gun. This avoids complaints and returned molds. It seems to me the original poster is expecting custom moulds at production prices.

[W.R.Buchanan]

Lyman specs it's moulds with Wheel weights or at least that's what I was told by their production manager. Getting RCBS to revise their process is something that is needed, and agreed to by the General Manager. All they are doing is increasing the size of thier cherries and if it works for me they will probably resize all of them. A cherry makes 45 moulds, So they go away pretty fast, and making one .002 bigger is not going to cost any more than making a new one anyway. the original sizes were based on the shrink rate of linotype for all moulds. This is not common practice.

They didn't know they had a problem, (mainly because enough perople havn't complained) and if you saw the response I got from them the first time it would be easy to see that the people involved didn't know anything whatsoever about casting bullets.

The new guy is at least willing to listen, and discuss options intelligently. We talked machine shop for 45 minutes on the phone. He wouldn't have done that if I was a crack pot.

Gun is a Marlin 1895 Cowboy in 45-70 purchased in 2005. Groove dia is .4595.

These bullets sized to .459 do not size completely (40% at best) and gas checks fall off.

The mould is undersized!

Load is 30 gr of 5744 for about 1350 fps.

The mould is undersized, and the bullets do not grip the bore well. simple as that.

I experienced this same exact phenomenon with my 1894 Cowboy with a .431 bore shooting bullets sized to .429. Too loose for the bore , and they don't get gripped by the rifling well and as a result don't get spun up in time.

I'm not looking for custom anything I 'm just loooking for industry standard.

I knew I'd get S^&* for this post .

Randy

[PacMan]

No one trying to give any bs here. Not knowing that you were shooting a Marlin with .4595 grove dia. that you did not post in the orginal post cause some confunison.
Now having said that the specs for that mold is .458 which you said it cast at 458plus and going in it would appear to me that you expected it to cast a .460 plus bullet and slamed RCBS for selling an inferior mold. That same bullet shot in a friends Ruger#1 stablizes without any problem.
Some of the time the problem falls more in the rifles court than it does the mold.Same as with your 44mag. The way i see it is that the bore/grove dia. on the Marlins are out of spec.not the mold.

The GC falling off is not good and does need attention. The other side of the coin is that the larger you size the bullet the larger the shank may need to be to get a good crimp. Dealt with that problem with a .361 bullet that i was sizing to .360 for my Marlin. Sized to .358 they were tight but fit rater loose when sized to .360. The shank was a little to small for sure.

[cbrick]

Before anyone slams me for slamming RCBS, don't bother, I love RCBS molds and sing their praises every chance I get and I have about 25 of them.

That said, I cast with WW almost exclusively and have sent several RCBS molds to Erik Ohlen to have the driving bands enlarged because they cast too small for the firearm they were intended for. The variation in measured bore diameters across most all firearm makes is very real and the simple truth is that it is far easier to size down a couple of thousands than to make an undersized bullet shoot well and/or not lead the bore.

If RCBS does in fact increase their average as cast dimensions by a couple of thousands I for one would be an extremely happy camper. Erik may not be though.

As for the gas check shank being too small and the check falling off, I have never experienced this with an RCBS mold. As long as the check can be crimped on, a slightly small shank is much better than not being able to get the check on. I have long wished Hornady would spec their checks slightly larger for all calibers and brands of molds.

Bullet tumbling at 50 feet? I have to agree that sounds much more like a twist/velocity problem than an undersized bullet. An undersize bullet would be a definate leading problem but dang, tumbling at 50 feet?

Now if RCBS wants to make a real change with their excellent line of bullets molds they will start producing 4 cavity molds. Oh the joy of that. I have about 70 molds and in just about every case the RCBS bullet design out shoots the similiar bullet design from SAECO, the only problem with RCBS is being limited to a two cavity mold.

Rick

[PacMan]

I along with others would most likely buy more production molds if they would cast to a advertized larger dia. Now the guys who would get hurt the most are the custom guys that cut molds at larger dia. to meet the needs of guys requiring a larger dia. Us Marlin owners.
Having said that a person should not expect a mold to cast larger than the stated dia. on the mold.
To eliminate a mold dia. of .458 from their line would disapoint some for sure with .457 or so bores and flys in the face of the theory that sizing a bullet ruins it.

[cbrick]

flys in the face of the theory that sizing a bullet ruins it.

Not really a theory, it's an old wives tales from the days before virtually all sizer dies were made with a taper lead in. Still endlessly repeated but repeating it does not make it so.

The vast majority of casters size their bullets today and if sizing a couple of thousands is needed so be it. This is a far better situation than shooting undersized bullets. Bore diameters do vary considerably, my 30-30 has a great bore, clean sharp rifling, no loose or tight spots and it measures .3092" from one end to the other. I doubt very much it's only me, I have about 15 30 caliber molds and only a couple of them cast this large, thank goodness for Erik.

Rick

[W.R.Buchanan]

Please to understand I wasn't slamming RCBS. I was slamming the bozo that sent the mould back to me with a lame explaination. Also Please to understand, he HAS been corrected.

The new GM was very interested in what I had to say and we talked for 45 minutes. When he saw the reply to my to my original request sent back to me with the untouched mould, his first statement was "if the mould was right then why did this guy send it back to us with a detailed letter explaining exactly what was wrong?"

My whole intent of my converstation with RCBS was to get them to revisit the policy of specing mould dimensions using the srink rate of linotype as opposed to Wheel Weight Material.

Had this mould been dimensioned using the more common shrink rate, everything would be Hunky Dory.

I don't have any linotype material but I bet this mould would make .460-461 bullets with linotype. Which would size up just fine.

Nobody I know uses linotype for .45 cal bullets. In fact most use pure lead for bullets for Trapdoor rifles or other black powder applications. Most guys casting for .45-70's in newer guns are going to use wheel weights.

I see linotype as something to use for .30 cal bullets for a rifle when you are pushing 2000 fps, and don't want to heat treat. IE why use it?

This was a case of using the same material to develop all of their mould dimensions across the board, when they should have used a more common material for most all of the larger mould's dimensions. You just can't assume everything acts the same. You have to test every product individually. This was not done apparently, but is now being looked at.

Some good will come from this.

Randy

[MikeS]

When did Lyman start spec'ing their moulds using WW? I was under the impression that they spec'ed their moulds with their #2 alloy. And as for getting RCBS to spec their mould to WW might not be the best idea. WW's are going to sooner or later start drying up, and when they do, everyone is going to have to start using another alloy to cast their boolits with. Add to that the fact that WW alloy is a moving target, and has changed over the years, so if you're casting with WW's you collected over the last 20 years, your alloy is going to be different than somebody that goes out today, and get's a 5 gallon pail of WW's today. A much better idea would be for RCBS to use a commercially available alloy as their spec'ed alloy, much like SAECO does. SAECO uses Taracorp's Lawrence Magnum alloy to spec their moulds, and it's composition is almost identical to RotoMetal's Hardball alloy, the only difference being the Taracorp alloy has 1/4% arsenic in it, and the Hardball alloy doesn't. Even if those 2 companies (Taracorp, and RotoMetals) were to go out of business, or just stop offering that alloy, as it's composition is known, it wouldn't be hard to duplicate. I wonder if RotoMetals could be talked into changing their Hardball to include the 1/4% arsenic, and reduce the lead content by the 1/4%, then the 2 alloys would be identical. I'm not saying that Hardball is the best alloy to spec a mould to, only that it's a known alloy, and so is easy to either get, or mix up.

I just looked at an RCBS mould listing, and according to is, the only boolits that are spec'ed with linotype are their rifle & silhouette moulds. An across the board change to any one alloy would be stupid, they probably need to leave the SIL boolits in linotype (I think that's what silhouette shooters use, but could be wrong), and spec the other rifle boolits in RotoMetal's Hardball, or even Lyman #2 alloy.

[MT Chambers]

I have the same Rcbs .45-300 mold and it drops them undersized and the mold isn't very useful for me anyways.

[cbrick]

I just looked at an RCBS mould listing, and according to is, the only boolits that are spec'ed with linotype are their rifle & silhouette moulds. An across the board change to any one alloy would be stupid, they probably need to leave the SIL boolits in linotype (I think that's what silhouette shooters use, but could be wrong), and spec the other rifle boolits in RotoMetal's Hardball, or even Lyman #2 alloy.

Very few silhouetter's use straight lino, at 12% antimony it is far too brittle for shooting steel targets. The 55 pound 200 meter T-1 steel ram just stands there looking at you when the bullet shatters on them. Don't ask how I know. :roll:

Rick

[fredj338]

I have an older mold that drops ww bullets right at 0.4595" & I size to 0.459". The shoot quite well in my 1886 Browning & Marlin GG. One could always lap them slightly larger.

[Lloyd Smale]

while your on the phone jump them about making some 4 cav molds. I think there molds are great. Much better then a lyman 2 cav. Just would be nice to get them in a 4 cav.

[theperfessor]

I love my RCBS molds. I'd love them even more and would probably own 5x or 10x as many as I do now if they would offer them in four cavity versions, at least the ones intended for use in handguns. I can live with a one or two cavity rifle bullet mold, but not in 9mm/.38, .41, .44, .45, ... you get the picture, but RCBS doesn't.

[W.R.Buchanan]

I offered up points that they might look at and he agreed. I don't think they will change everything they do, but if they do have a close look maybe they will change the bullet moulds that would be used with WW or Lyman #2 which is close to WW.

Linotype is a bit farther away from WW than Lyman #2, and since it is harder it shrinks less. That is where the problem lies.

For most bullets above .30 cal linotype is not the material of choice. WW, Lyman #2, and a variety of other softer concoctions are the materials of choice. Therefore those moulds should be developed using shrink rates for the softer alloys.

I don't see an across the board change for everything. Hopefully they will change what is needed.

I will mention 4 cav moulds to him next we speak. But the short answer is, The reason why they have not produced them in the past is because they have a single Bridgeport mill fixtured to cut mould blocks in a fixture that closes the block halves onto the cherry.

It isn't big enough to swallow 4 cav blocks.

Until they can successfully get their CNC machinery to cut mould blocks the way Mihec and others do it, I don't see 4 or 6 cav blocks happening. They are actively trying to get these machines to run this new process, and when they do get it figured out, I see them expanding their line.

Randy