how to explore new loadings from scratch

[P7M13]

I'm kinda curious since #7 is a slower powder could i start with the max load for that for 460 Rowland and dail that back like 5-7% for starters and slowly work up?

I wouldn't suggest that.
Burn rate and energy density (joules per gram, etc) dictate powder crossover compatibility, i.e. using one instead of another.
Without knowing accurately the values for each, is a form of roulette -- some of the worst odds in any gambling house.
Do you have a chronograph?
It's a good idea to know the internal capacity of your case with the bullet seated to your desired OAL. There's a bunch of threads about surplus powder 7383, which is prone to extreme pressure spikes with compressed loads. Those threads outline the following method to determine case capacity.
Suggest you take a 45ACP case (if your cheap), 460 Row if you want the real deal, drill out the primer flash hole to 1/4". Seat and crimp a bullet to the desired OAL, then fill the case with your powder from the bottom to determine the 100% case fill for a given powder.
Then, for energy comparison, if you look at 10mm loading values for a 200gr bullet, (10mmLoaded.com, iirc), 9.8gr of #7 yields 1063 fps MV. 11.20gr of #9 yields 1185 fps MV. The two are apples to grapefruit. Be careful.

 

[DizzyJ]

These guys have echoed what my thoughts are on the subject. If a common powder is not listed, it's for a reason. The component manufacturers spend a lot of time, money, expertise and development generating load data for these cartridges.

Experimentation with certain powders not listed may be frustrating to downright dangerous depending on the circumstances.

 

[po18guy]

Call the powder company for suggestions. Work up or down as needed.

 

[Dr Prepper]

I feel your pain.
Wasn't aware you had been to 460, so tossed that one over the fence.
You seem experienced, but I'll flog the horse.
To me, this is "tread carefully" territory. You're upping the pressure significantly on a low pressure round to get the velocities that Rowland is touted for. Even though the barrel is designed for higher pressure, bad pressure spikes in pistols can lead to some major owies and a trip to the ER. IF my gun was an all metal frame, I would feel a wee bit better about that. Glock? Oof.
Damn, I hate to sound like "that guy."

I think in this case (no pun intended), Quickload is your friend. Know anyone who has it?

In my experience, if you don't find a powder listed for a specific cartridge, and the powder has been around a while, there's good reason.

General rule of thumb, powders burn most efficiently when they are in a 85 - 100% fill scenario. Some get really ugly below, and some when above, more so when compressed. A bullet set-back on chambering, leading to a KB in your hand is a good example of the latter.

Not having loaded for the Rowland, I can't offer any wisdom. What I can offer, if you make it down to Portland, is some Longshot or 800X for you to try. I was holding on to those because they're ideal in 10mm. #9 is too, so I can swap you some.

Yeah. Thats right. I think i read on the can now that i think about it, that #9 is good for heavy 10mm loads which also kinda said to me that it would work in 460.
I do have some heavy 10mm's as well.

 

[Dr Prepper]

I wouldn't suggest that.
Burn rate and energy density (joules per gram, etc) dictate powder crossover compatibility, i.e. using one instead of another.
Without knowing accurately the values for each, is a form of roulette -- some of the worst odds in any gambling house.
Do you have a chronograph?
It's a good idea to know the internal capacity of your case with the bullet seated to your desired OAL. There's a bunch of threads about surplus powder 7383, which is prone to extreme pressure spikes with compressed loads. Those threads outline the following method to determine case capacity.
Suggest you take a 45ACP case (if your cheap), 460 Row if you want the real deal, drill out the primer flash hole to 1/4". Seat and crimp a bullet to the desired OAL, then fill the case with your powder from the bottom to determine the 100% case fill for a given powder.
Then, for energy comparison, if you look at 10mm loading values for a 200gr bullet, (10mmLoaded.com, iirc), 9.8gr of #7 yields 1063 fps MV. 11.20gr of #9 yields 1185 fps MV. The two are apples to grapefruit. Be careful.

Sorry re reading my post i miss spoke. I meant to say since #7 is a *FASTER powder than #9 i could somewhat use it.
I like the idea of calling the powder maker.
To answer someones replay i get that component makers spend alot of time and money on loads work ups. But 460 rowland isnt really one of them. Its just not a common cartridge.

 

[Dr Prepper]

I wouldn't suggest that.
Burn rate and energy density (joules per gram, etc) dictate powder crossover compatibility, i.e. using one instead of another.
Without knowing accurately the values for each, is a form of roulette -- some of the worst odds in any gambling house.
Do you have a chronograph?
It's a good idea to know the internal capacity of your case with the bullet seated to your desired OAL. There's a bunch of threads about surplus powder 7383, which is prone to extreme pressure spikes with compressed loads. Those threads outline the following method to determine case capacity.
Suggest you take a 45ACP case (if your cheap), 460 Row if you want the real deal, drill out the primer flash hole to 1/4". Seat and crimp a bullet to the desired OAL, then fill the case with your powder from the bottom to determine the 100% case fill for a given powder.
Then, for energy comparison, if you look at 10mm loading values for a 200gr bullet, (10mmLoaded.com, iirc), 9.8gr of #7 yields 1063 fps MV. 11.20gr of #9 yields 1185 fps MV. The two are apples to grapefruit. Be careful.

Yes i do have a chrony, and careful is my middle name. at least now it is..

I actually started collecting reloading gear about 12 years ago and refused to load ANYTHING till i got a good chronograph. Kinda glad i did too. Velocity and pressure signs are kinda interesting to say the least.

Yeah im thinking about doing some h2o cap measurements as well as powder charge volume tests.

Im starting out with longshot, a tried and true recipe.


Regarding the shotgun loading i couldn't find any recipes for the newer grey AA hulls. I think i still have some older AA hulls. Id have to check.
Mostly id like to take some wally world birdshot loads (still new factory loaded) and cut them, empty them maybe down charge 10% maybe 12% and then reload them with the same components except with the slug or 00.
I've clearly watched too many tauofelatermous videos! Lol.

 

[Dr Prepper]

i couldn't find any recipes for the newer grey AA hulls.

At least not yet, I haven't hardly looked much. Admittedly.

I thank ye all very much for caring for my safety. One can easily get carried away in this hobby, just hopefully not by pallbearers!