Bullet Weight vs Powder Type vs Recipe

[gungate]

I am confused how reloading recipe are formulated. For instance, I reload 6.5 Grendel. I use 123 grain bullets and the recipe (I use the Hodgdon recipe calculator) specifies to use Accurate 2230 (among others). If I move to a 129 grain bullet, there is no recipe using any Accurate powder. For the 123 I can use 2200, 2230, 2450, 2520, LT-30 or LT-32.

What I am considering is casting my own bullets. I found a mold that makes 140 grain bullets, for which I can find no recipe anywhere.

My question is, what is the process for developing my own recipe?

Also as an aside, why in the F are there soooooo many powders?

 

[85MikeTPI]

Find a close recipe, drop it by 10% and test, test, test

Mfg don’t have the resources to test every combo, so if you’re going off script, you take your time and test carefully

Many people forget to look at the bullet type and COAL of recipes, these could drastically change the pressures and why going off-script takes time and effort.

So many powders because of capitalism and so many features/options. You can probably get away with 3 or 4 on your shelf to suit all your needs, but others may suit a particular caliper perfectly and you’re able to squeeze that extra 10% performance from it over a more generic

 

[Rockzilla]

Lyman cast boolit manual or the new manual

Like said find load close, with the basic bullet shape, drop 10% then develop

-Rock

 

[mpollan1]

Also as an aside, why in the F are there soooooo many powders?

I often wonder that about calibers...

 

[E.Shell]

Generally speaking and in any given cartridge, faster powders are more suitable for lighter bullets, slower powders are better for heavier bullets. As you move up in bullet weight, faster powders are dropped off the list and slower powders are added.

The reason for so many different powders is that each manufacturer strives to provide powders with enough variation in burn rate to address many cartridges with multiple bullet weights. When you then multiply that by the number of competing manufacturers, you DO end up with a great variety.

 

[DanGuy48]

I am confused how reloading recipe are formulated. For instance, I reload 6.5 Grendel. I use 123 grain bullets and the recipe (I use the Hodgdon recipe calculator) specifies to use Accurate 2230 (among others). If I move to a 129 grain bullet, there is no recipe using any Accurate powder. For the 123 I can use 2200, 2230, 2450, 2520, LT-30 or LT-32.

What I am considering is casting my own bullets. I found a mold that makes 140 grain bullets, for which I can find no recipe anywhere.

My question is, what is the process for developing my own recipe?

Also as an aside, why in the F are there soooooo many powders?

What about this? Deselect “all” on left menu and select just 140 gr.

Shooter's Reference Load Data for 6.5 Grendel

shootersreference.com

 

[gungate]

What about this? Deselect “all” on left menu and select just 140 gr.

Shooter's Reference Load Data for 6.5 Grendel

shootersreference.com

Well shit, that is the first I have seen that page. I think that solves all of my issues. Thank you!

 

[DanGuy48]

Well shit, that is the first I have seen that page. I think that solves all of my issues. Thank you!

 

[Growler215]

Typical "recipes" are developed using an instrumented test barrel to determine the pressure for each tested load. Through testing, they then find the charge weight for a given test powder/bullet (with a specific brass and primer type) that gives the highest velocity without exceeding the SAAMI maximum allowable pressure for that cartridge. That's the "max" load. The "starting" load is then typically just specified as 10% less.

In addition to what others have stated about why there are so many different powders, I think the manufacturers have also tried to develop "value added" characteristics beyond just burn rate. Examples include the low temperature sensitivity of Hodgdon "extreme" powders, which give more consistent velocities under a wider range of temperatures, the "flash suppressants" added to some powders, and the "anti-coppering" additive in some powders.

Well shit, that is the first I have seen that page. I think that solves all of my issues. Thank you!

None of these 140 gr loads are for a cast bullet, so you still need to figure out how much to "back off" for a cast bullet. Typically you will get more pressure and velocity for a given charge weight with a lead bullet.

 

[gungate]

Typical "recipes" are developed using an instrumented test barrel to determine the pressure for each tested load. Through testing, they then find the charge weight for a given test powder/bullet (with a specific brass and primer type) that gives the highest velocity without exceeding the SAAMI maximum allowable pressure for that cartridge. That's the "max" load. The "starting" load is then typically just specified as 10% less.

In addition to what others have stated about why there are so many different powders, I think the manufacturers have also tried to develop "value added" characteristics beyond just burn rate. Examples include the low temperature sensitivity of Hodgdon "extreme" powders, which give more consistent velocities under a wider range of temperatures, the "flash suppressants" added to some powders, and the "anti-coppering" additive in some powders.


None of these 140 gr loads are for a cast bullet, so you still need to figure out how much to "back off" for a cast bullet. Typically you will get more pressure and velocity for a given charge weight with a lead bullet.

I was going to go with the minimum load and test with a chronograph. I know that doesn't equate exactly to pressure but I have no way to test pressures.