Lyman 454485, why?

[J Miller]

A member of Levergunluvers fourm posted a large pic of all the Lyman molds.
http://www.three-peaks.net/bullet_molds.htm
In there, down towards the bottom is the bullet #454485. This is a GC version of the 454190. Considering that the 454190 is basically a .45 Colt factory duplicate bullet, I'm curious if anybody here has any idea of why Lyman produced a GC version of it.

I actually have a double cavity 454485 mold and have cast some from it. But they don't shoot near as well as the 454190 version. The lack of GC does affect it's performance.
And I've never bought any .45 Cal gas checks. I keep saying someday I should, but I never do.

I wonder how this bullet with a GC would work from a rifle?

TIA

Joe

[felix]

The center of gravity had been moved foward by cutting a gascheck shank. That will throw off the balance. Adding a check might help some, but copper/zinc is considerably lighter and will do only slightly better. You MIGHT overcome your problem somewhat with satisfaction when you apply the check and shoot the boolit quite fast. ... felix

[44man]

Felix, although you are right about the weight change, it is minimal but he is losing a drive band and it is like shooting a much shorter boolit for the rate of twist. I bet if he puts a check on it, it will shoot just like the other one.
Plus, the base doesn't seal like a flat base and they shoot like a bevel base which has never shot for me so I remove it from the mold.
Guys just don't understand the relationship between twist and boolit length and few boolits designed for a check will shoot good without it unless it is already too long for the rate.
I had a 30 cal gas check boolit that would center a nickel at 100 yd's go through paper sideways at 50 yd's without the check. I put some in my lathe and cut the check portion off, still sideways at 50. Balance---maybe, but I still say it did not match the twist rate.

[J Miller]

What I'm trying to find out is why this modification of a proven design was made.
The 454190 is a very accurate bullet out of every gun chambered for .45 Colt I've shot it from.
So, why mess with success? Why the modification of this bullet to a GC design?
That is what I'm trying to find out.
I don't know when this mold was made, but I do know it hasn't been offered by Lyman for many years. And the mold I have was quite old when I got in the early 70s.

As for the accuracy thing, the twist and bullet length vs weight is still confusing to me. That 454485 bullet doesn't show the accuracy that the 454190 does because it doesn't have the same length bearing surface for the same weight?
But bearing surface length alone does not cause inaccuracies. For instance the Lyman 452460 200gr SWC is a flat base bullet with two grease groves and a shortish nose. It has a short bearing surface length, and with the two grease grooves even less actual bearing surface. Yet it is a superbly accurate bullet. I've used it from the .45 ACP chambered semi-autos I've owned, and I shot it from .45 Colt and .45ACP revolvers and rifles with great results. It's bearing surface is shorter than the 454190 bullet. So there must be a correlation between the bearing surface length and the bullet weight.

As I said I'm confused about all this. I'm not very scientific really. I try 'em and if they work I'm happy, if they don't. Well I try something else.


Joe

[44man]

Anytime boolit length is changed, the velocity also has to match. If the bore has a fast twist, a short boolit has to be shot a lot slower. If you have a slow twist and try to use too long a boolit, you might not be able to drive it fast enough for stability. Everything is relative. If you attain high velocity with a gas checked boolit with accuracy, then leave the check off, you must slow it down to get it to shoot. You can't use the same load!
If you are shooting a short boolit at ACP velocities and slow .45 Colt velocities, they will work fine but step them up and you will find a difference. Each boolit needs a load workup. If you shoot one good, don't expect a change like leaving the check off, to shoot with the same load. It only takes a tiny change in a boolit to go from great to useless. Two boolits exactly the same but with a small difference in the grease grooves can also require a total load workup.
When you work up a load, you are speeding up the spin on the booit with each increase and when it is optimum for it's length, it shoots best. It is not the actual velocity of the boolit that makes it accurate but the stability.
Spin a gyroscope real slow and it wobbles, speed it up and it runs smooth until it slows down where it goes crazy and flops all over.
You CAN over stabilize a rifle bullet and it won't shoot for beans until it gets down range where it will "go to sleep", so to say. At handgun ranges, it won't happen.
Boolit spin is very important.

[MT Gianni]

I don't see it on the chart or at cast pic's. but I thought the GC version was 454490?

[J Miller]

MT Gianni,

If you'll count six rows up from the bottom of the big mold pic I linked to above you'll see the 454190 forth from the right, and the 454485 on the extreme right.
The 454190 is the plain base bullet, and the 454485 is the GC version.

Joe

[MT Gianni]

I see that but I have seen a 454490 not listed on either chart for sale as a gc version. Just curious about the numbers.

[floodgate]

J Miller:

The reason #454485 was introduced (in Ideal Handbook #40, 1955) was that someone clearly felt a GC version was needed, probably for hotter loadings. It was dropped after 1978; presumably for the reasons noted in the various posts above. Ol' Elmer always felt that GC bullets in revolavers were answers looking for a question.

floodgate

[Bass Ackward]

I had a 30 cal gas check boolit that would center a nickel at 100 yd's go through paper sideways at 50 yd's without the check. I put some in my lathe and cut the check portion off, still sideways at 50. Balance---maybe, but I still say it did not match the twist rate.


My experience is just the opposite. I have a 150 grain spitzer in a 10 twist 30 that is just an average performer until you goose it to 2600 fps where it will move sub MOA. And that is 14 BHN. I suspect that hardneing it a little would allow me to move on up with it. But that is where the Mil Dots are calibrated, so it is counter productive to go any faster.

Meplat size, bullet weight, balance point, load conditions and most of all velocity contribute to .... proper twist rate utilization. What we as reloaders have to do is find the balance to make it work. Hardness is a sub-factor to bullet weight and velocity because if you can drive it to the velocity it needs under your conditions, then it simply ain't going to perform for you. You learn that when you shoot softer bullets for awhile. :grin:

Match the bullet hardness for the conditions is an old saying that simply allows you to bypass these factors without having to explain them cause we still can't draw the line. So for me it's a package deal. Eliminate bearing length and it would seem that I need to increase hardness to maintain formula balance. Hard being a relative term. If I was shooting 8 BHN, I may now need 12 or more without a check.

That's my guess why simply removing a check can work for some people and not for others. You might say that removing the GC is a test for the proper hardness. If you can shoot well without it, you had room to go softer in the first place. Or why a PB outperforms a BB for some and not others.

I am able to shoot BBs just fine. If you don't create obturation issues by going harder with the BB, and again that is a relative term, you may see better results. But you have to either change load conditions OR hardness before you can draw any conclusions.

It's all a trade off. And it's the same way with copper for me. I always have to drive a boat tail faster than I do the same weight / shape as a PB. So a BB is nothing but a boat tail cast and it better be hard enough to withstand more pressure / velocity. If your gun or load conditions require you to seal, you either need to be the proper size or obturate up. And a PB has the edge at that point. Plus it keeps the balance point back where the bullet is easier to stabilize. But BBs tend to make losy obturators.

[44man]

Now Bass, you know a 150, 30 cal is a great match to a 1 in 10 twist! Just make the bullet spin where it wants to. If you want to have fun, take some 180's or 220's and try to get them to shoot from a 1 in 12 or 1 in 14. You can't get the speed up high enough to make them stable!
All you have said is correct, it is a game of trade off's without a doubt. We just have to realise that there are limits on both sides, too long or too short for the rifling makes it next to impossible to make the boolit work.

[Bass Ackward]

Now Bass, you know a 150, 30 cal is a great match to a 1 in 10 twist! Just make the bullet spin where it wants to. If you want to have fun, take some 180's or 220's and try to get them to shoot from a 1 in 12 or 1 in 14. You can't get the speed up high enough to make them stable!
All you have said is correct, it is a game of trade off's without a doubt. We just have to realise that there are limits on both sides, too long or too short for the rifling makes it next to impossible to make the boolit work.


44,

Just realize that a 150 cast is probably like a 110 grain jacketed length wise. So it IS a VERY short bullet for a 10 twist.

And believe it or not, 12 and 13 twist is what the benchresters use for 180- 190 grain bullets.

[floodgate]

Gianni:

#452490 was also a GC, but was a "fat" SWC design, cataloged from 1961 to date (2007), at 255 grs.

floodgate

[shooter93]

If the bullet is shorter....I wonder if it was made to help the feeding in guns like Winchester 73 replicas....mine just barely feeds the 250 rnfp's

[beagle]

I've often asked the same question about these two designs. Can't understand why the 485 was made.

About 5 years ago, I picked up a old 454485 factory HP and due to the GC provision, it wasn't getting much use so we dehorned it and made it a PB. Shoots really well in the .45 Colt and also works well in the Ruger .45 Convertible in .45 ACP cases.

Then we HP'd an old 454190. It also shoots well in both calibers.

The only difference is that the #485 weighs about 1 grain more which is really insignificant.

I have tried the GC 485s in a .45 Colt rifle and they didn't set the house on fire with accuracy there either.

Based on these experiences, I use whatever is available on the bench./beagle