Maximum PCC energy

[milktree]

Say I wanted to optimize for maximum muzzle energy out of a 9mm carbine without exceeding safe chamber pressure: light bullet & slow powder? I have a bunch of 115gr. projectiles, so assume that weight. Which powder? HS-9? 2400? H110? Reloder 15? (That’s a joke)

Obviously such a recipe would work poorly out of a 4" handgun, I’m not looking for a “do-everything” recipe, I’m looking for one that has the most power from a carbine, even if it sucks out if a handgun.

As a follow up: same question, but .38 spl. 124gr. bullet, maximum energy out of an 18" barrel without exceeding .38 spl (+P) chamber pressure.

 

[NavelOfficer]

Kind of difficult to be specific w/o test equipment to accurately measure chamber pressures, but using published load data and the following:
How to Calculate Bullet Impact, you should be able to get close.

 

[milktree]

Kind of difficult to be specific w/o test equipment to accurately measure chamber pressures, but using published load data and the following:
How to Calculate Bullet Impact, you should be able to get close.

I can calculate muzzle energy with a chronograph and the bullet weight, that's easy.

I think it's reasonable to trust that published recipes will be safe (won't have excessive pressure).

The question is about powder and projectile choice. Does a heavy bullet allow for a wider selection of slower burning powders so I can use the full 16" of barrel, or am I better off with a light bullet?

 

[NavelOfficer]

Well, you have the solution, shoot, measure and calculate.
If muzzle energy is a result of bullet weight and velocity, calculate which combos give the higher result. Based on Hornady 3rd edition muzzle energies in 9mm, .38 Spl and .45 ACP are greater with light bullets going much faster. You need to test loads in your specific rifle and compare results.
FWIW, Lyman 47 lists rifle data for 9mm, but charge weights are not different from pistol. Longer test barrel length does show higher velocities, of course.
Most heavier bullets have load data for slower powders, not so much with light bullets. Hodgdon offerings CFE Pistol and Longshot generally give top velocities; H4227 (in .38 Spl. +P), too, but at twice the charge.

 

[38ExtraSpecial]

Say I wanted to optimize for maximum muzzle energy out of a 9mm carbine without exceeding safe chamber pressure: light bullet & slow powder? I have a bunch of 115gr. projectiles, so assume that weight. Which powder? HS-9? 2400? H110? Reloder 15? (That’s a joke)

Obviously such a recipe would work poorly out of a 4" handgun, I’m not looking for a “do-everything” recipe, I’m looking for one that has the most power from a carbine, even if it sucks out if a handgun.

As a follow up: same question, but .38 spl. 124gr. bullet, maximum energy out of an 18" barrel without exceeding .38 spl (+P) chamber pressure.

What is the end use?
Couple of things to note.
Maximum energy isn’t always right for the application.

A lighter bullet at a faster speed can show more energy but might not penetrate. Which could be what you’re looking for if you want to grenade varmints

Also bullets are designed to work at specific speeds. If you push it too fast it may not act as advertised as far and expansions and penetration.

Companies like Speer make bullets specifically for say 44 mag vs 44 special knowing the velocity variations.

Look into the guys running 9mm major through race guns and use the data with the slowest powders and you will probably get the most velocity from that.

 

[DW357]

Look into the guys running 9mm major through race guns and use the data with the slowest powders and you will probably get the most velocity from that.

This is what I was going to suggest.
I think the most popular powders would be HS-6, Silhouette, AutoComp, AA7, N350, or 3N37 to name a few.

@SJan would be the guy to ask around here on NES. I’m sure he’ll have some advice.

 

[M1911]

I believe 9mm major loads are well above SAAMI pressures. They are safe in race guns that are designed specifically for 9mm major, but it wouldn’t surprise me if they are dangerous in a carbine not designed or tested for those pressures.

 

[38ExtraSpecial]

I believe 9mm major loads are well above SAAMI pressures. They are safe in race guns that are designed specifically for 9mm major, but it wouldn’t surprise me if they are dangerous in a carbine not designed or tested for those pressures.

I believe the issue here is that there isn’t a saami spec for 9mm major.
Some guys have run Quick Load and see about 40k PSI for major loads.
Not too high over the 38,500 limits for +P which should be safe in almost any modern firearm. Check your manual to make sure.
That being said it will wear the firearms faster with a steady diet blah blah blah.
One other thing the 9mm major guys do it to seat the bullets as long as possible to increase case capacity. It doesn’t seem like it would make much of a difference but it does. In such a small case, little changes in capacity make a huge pressure increase or decrease.
See photo.
All that being said this is a small efficient high pressure cartridge. You probably won’t be able to get enough of a slow powder in there to have significant gains the way you can with a 357 magnum.
200 fps seems to be the average increase for a rifle barrel vs a standard 5” barrel.

 

[SJan]

This is what I was going to suggest.
I think the most popular powders would be HS-6, Silhouette, AutoComp, AA7, N350, or 3N37 to name a few.

@SJan would be the guy to ask around here on NES. I’m sure he’ll have some advice.

While I have a good amount of experience in the 9mm (AR) carbine, I do not play wit the 9 major race gun stuff.

My AR 9 load is for a 147g at 900 fps tuned for lightest perceived muzzle rise. Quite the opposite I assume than the OP. I would be hesitant to shoot what the OP will likely load out of my carbines without changing my recoil system.

I don't know the platform the OP is using, but if it's a blowback, I suggest slow and careful load development.

In my research and experience, the small case volume of 9mm does not gain much if any velocity beyond a 8 or 10" barrel length.

Regarding 9 major loads for race guns, the power factor ( bullet weight x fps ) is achieved safely in part by loading longer than Sammi spec. The 2011 magazines can accommodate 1.25"+ and the barrel chamber is cut accordingly. Again o don't know what the OP is shooting, but my AR 9 chamber will not accept that COL