Cast 9mm v Powder/Case Volume

[Fizz]

I'm loading 124gr cast boolits from a Lee TL Mold (TL356-124-2R). The projectiles are sitting over 4.1 grains of Unique with 1.105 OAL.

I'm fine with how this performs and cycles my EMP 100%. However, I want to start seeing if the higher charges result in any better accuracy (not that the current performance is bad). Though, I suspect that the boolit's compressing the charge as it is.

Issue or non-issue?

Then again, I'm not sure my 3 inch barrel can utilize it anyway.

[mark501w]

Go to a lighter bullet.

[Fizz]

Go to a lighter bullet.

My thought was the same, but somehow Alliant posts a recipe of 5.8 Grains of unique behind a Speer 124 gr GDHP. I would think 5.8 grains is already spilling out of the case (exaggeration) before you even put the projectile in.

[CSACANNONEER]

There's plenty of room in the case.

[Fishslayer]

My thought was the same, but somehow Alliant posts a recipe of 5.8 Grains of unique behind a Speer 124 gr GDHP. I would think 5.8 grains is already spilling out of the case (exaggeration) before you even put the projectile in.

I load my 124gr Bear Creeks with 4.2gr of Green Dot. Data says I can use more but the case sure looks like it's getting full. I'm fairly certain I'm compressing the charge a bit as it is. The load I use performs well enough for range fodder so I just use that.

[J-cat]

Compressing Unique is no big deal. Have you compared case body expansion of your reload to factory ammo using the same brass? For example, in my Sig factory FC ammo expands to .390" and +P to .392". I keep my handloads to .390" or so.

[Fizz]

Compressing Unique is no big deal. Have you compared case body expansion of your reload to factory ammo using the same brass? For example, in my Sig factory FC ammo expands to .390" and +P to .392". I keep my handloads to .390" or so.

What point are you measuring since 9mm is tapered?

I know my boolits expand the case slightly more than FMJs but I know that's not what you're referring to.

[Ferrum]

There's plenty of room in the case.

^^^^ THIS!

With a 124g lead projectile seated to 1.105, there should be about 9.7g of useable case space. With a load of 4.1g of Unique, you should still have plenty of room.

[klewan]

If in doubt, just measure how deep the powder is in the case, measure the length of the bullet, then measure how much sticks out of the case. Subtract the stickout from the total length and the result will be how far into the case the bullet is into the brass. Take it from there.

[CalTeacher]

As already mentioned, don't worry about compressing Unique. My 9mm load is 5gr of Unique under a 125gr cast bullet. It shoots like factory 9mm and is a very clean load. I also load 5.8gr of unique under a 90gr frangible, which is also a compressed load. One of the benefits of Unique is that it fills the case making a double charge impossible.

[J-cat]

What point are you measuring since 9mm is tapered?

I know my boolits expand the case slightly more than FMJs but I know that's not what you're referring to.

I'm measuring the case body expansion at the widest point.

[tiller]

Fill ratio with unique is 6.2 grains to the top...


That is what I load 115's with ... And yes it's compressed