Choosing powders for 458 Lott from Quickload/Gordons Reloading Data?

[Nhoro]

Hi all,

Some theory questions to the experienced reloaders:

When choosing powder for a certain bullet/cartridge combination, what do you look for ?

So I have Quickload data and Gordons Relaoding Tool freeware. So looking for a certain velocity, you can use different powders. Some produce the same velocity at a lower maximum pressure. Some produce the same velocity at lower lower load percentage. What do you tend to choose and why ?

For example , S321 powder produces 2230 fps with 72 grains and 90.1 % load ratio with pretty high pressure(minimum load due to load %) (recommended powder from bullet manufacturer)
IMR 4895 produces 2211 fps with 72.5 gr with 93 % load ratio and much lower pressure(often recommended for Lott)
VV530 produces 2208 fps with 71 gr with 93.3 % load ratio and medium pressure.
VV135 produces same velocity and load in grains with about 101.1 % load ration and higher pressure.

Hit me with some reloading theory

 

[Luvthunt]

What bullet(s) weight for above powder charges?

 

[Nhoro]

515 gr Peregrine VRG -2 solids -so monlithic copper similar to North Fork

 

[shark_za]

Generally you want to be closest to 100% load ratio as this give the most consistent burn and Standard Deviations.
Anything over 90% is great. 101% is bad. Lowest predicted pressures and work up slowly.

 

[Shootist43]

Nhoro, of the three powders you named, I'd take the IMR 4895. your load density is above 90% and the pressure is low. How does the 2211 FPS compare to factory offerings using the same bullet? Contrary to some, I don't mind slightly over 100% load density, although I refrain from loads over 106%. How does the 2211 FPS fare as far as barrel time is concerned. Would slightly slower or faster times be more accurate?

 

[bruce moulds]

Generally you want to be closest to 100% load ratio as this give the most consistent burn and Standard Deviations.
Anything over 90% is great. 101% is bad. Lowest predicted pressures and work up slowly.

i would not say 101% is bad at all.
bruce.

 

[Nhoro]

Thanks for your comments. They confirm what I was thinking. Further background is that I do quite a few kids camps so the rifle is carried a lot. If it is used, it will be at 10 yards (apparently that is National Parks definition of when your life is in imminent danger !) So I am aiming for 2200 fps and an uncompressed load. Reliable in 45 degree heat and if it sits around for a year. So not really looking to push the boundaries.

 

[shark_za]

I guess a little compression can be ok. Where would you draw the line?

 

[bruce moulds]

as long as the load is safe, as much powder so that the case does oy bulge.
bruce.

 

[Nhoro]

Nhoro, of the three powders you named, I'd take the IMR 4895. your load density is above 90% and the pressure is low. How does the 2211 FPS compare to factory offerings using the same bullet? Contrary to some, I don't mind slightly over 100% load density, although I refrain from loads over 106%. How does the 2211 FPS fare as far as barrel time is concerned. Would slightly slower or faster times be more accurate?

Thanks, I agree that IMR 4895 then VV N 530 look most promising. Ironically, due to lock down, I have loaded a couple of rounds with IMR 3031- cos that is available right now due to the lockdown. I know the Vihtavuaori powders are good and usually (before lockdown) they are pretty available through a local importer. The makers of Peregrine push S 321 as the best powder-I think because of the low load density-They go to 80 gr as a max load. I would rather avoid Somchem powders as I think they are a bit lower quality and I want reliability. IMR 3031 is pretty close to S 321. So that was how I ended up with 3031- lockdown but I will be able to switch later.

Factory ammo is around 2300 fps with 500 gr solids and Peregrine max loads with their 515 gr are 2350 fps (S 321 powder and I am sure pretty heavy compression.So I am idling along at 2200 fps. And I cannot hear any powder moving when I shake the cartridge so I am closer to 100 % than 90 %. I guess a drop tube would maybe create the theoretical 93% load density.

Background is that I do quite a few kids camps in Zambezi valley and National Parks have decided that 10 m is about when your life is in' imminent danger'. So I am looking for absolute reliability- I would have 1 shot at 10 m.

 

[Nhoro]

Feedback-69 gr of IMR 3031 was a bit disappointing-2003 and 2020 fps but with nicely rounded primers and easy extraction. So after all my questions,Quickload was quite a way off ! Anyway, I will load some more cartridges this week when I can. Probably need about 72-73 gr of IMR 3031 which according to Quickload will be about 97 % load density. So it looks like Peregrines own data is the most accurate, 72- 80 gr of S321 which is fairly similar to IMR 3031

 

[Luvthunt]

In the 90s there was an article written in Handloader mag on the Lott the conclusion was IMR 4320 was the powder to use if you choose not to use Win 748.
Many powders such as IMR 4895,H4895,Rl 15, Imr 3031 Imr4064Win 748 and some I do not remember were tested.

 

[Shootist43]

Nhoro, do you have QuickLoad on your computer or are you using someone else to work up loads for you? Did you determine your fired case capacity or just use the "standard?"

 

[fourfive8]

Nhoro,
A very simple and direct way to determine 100% load density with a particular powder and bullet that will be crimped at a crimp groove in a particular case is to use something like a wood dowel. Use a fine pen or sharp pencil to mark the dowel at the bullet base, as shown in the pic, with the end of the dowel at the place where the case mouth will be crimped in the crimp groove. Add the powder to a sized and prepped case in small increments until mark on dowel is at case mouth when measuring the powder location in case. Weigh the powder. That is the weight of the 100% load density with that bullet, powder and case.
Pics of process using a 375 HH and Woodleigh 300 gr soft point . simple, direct, low tech, accurate

 

[Nhoro]

Nhoro, do you have QuickLoad on your computer or are you using someone else to work up loads for you? Did you determine your fired case capacity or just use the "standard?"

The guy I reload with has the program. In Zimbabwe, reloading needs a separate licence that now involves further rules on top of the gun license. It involves explosives law, extra lockups etc etc. So most guys reload through the local gunclub or through a friend-like I do. I used standard case capacity.

 

[Nhoro]

Nhoro,
A very simple and direct way to determine 100% load density with a particular powder and bullet that will be crimped at a crimp groove in a particular case is to use something like a wood dowel. Use a fine pen or sharp pencil to mark the dowel at the bullet base, as shown in the pic, with the end of the dowel at the place where the case mouth will be crimped in the crimp groove. Add the powder to a sized and prepped case in small increments until mark on dowel is at case mouth when measuring the powder location in case. Weigh the powder. That is the weight of the 100% load density with that bullet, powder and case.
Pics of process using a 375 HH and Woodleigh 300 gr soft point . simple, direct, low tech, accurate

View attachment 360654
View attachment 360656

Thanks

 

[Shootist43]

Here is a screen shot from QuickLoad showing a 500 Gr. Peregrine Bullet and IMR 3031 Powder in a 458 Lott.

 

[Nhoro]

Thanks Shootist43. That looks like I expected- The load is close to or around 100 % at 69 grains. and probably needs 3-4 more grains to get there. Did you by any chance run a ladder and maybe a powder comparison sheet ? Things are so complicated in Zim. I can probably get a reasonable supply of Vihtavuori powder- 130 and 530 were suggested by the local supplier. Interestingly those are sort of similar to IMR 3031 and 4895 so it seems those sorts of burning speeds are sweet spots.

 

[Shootist43]

Here is a load using V V 530C

V

 

[Shootist43]

Nhoro if you determine the weight in water contained in a fired but unresized case (with a convex bubble) QuickLoad's simulations will be much more accurate. Most often the actual volume is slightly higher than "standard."