Fast or slow burning powder for cast in 9mm?

A question came up in a discussion with a friend the other day..

In general, what is the preferred powdertype when loading cast boolits for 9mm luger, taken that all other factors are equal?
Sized to fit barrel, boolit weight, alloy hardness, velocity et.c.

A slow burning powder or a fast burning one?
Are any type better suited than the other, in general?

I have never had any luck with lead in 9mm, poor accuracy, leading, unstable boolits and so on, to the point where I have put casting for 9mm aside.
But now, since I have reached such great results in my other handguncalibers, I'll give it a new try..

I use vithavouri powders, and in the manual they lists loads from N320 to 3N38 for the same 124gr boolit..

My goal are top accuracy and velocities around 1000f/sec

I would suggest N-312 and/or N-320, I like BE, W231/HP-38 and these are the closest powders.

Yes fast burn rates and, as always Check a reliable load manual.

The problem most people have in loading 9MM is:
1) Swaging the boolit size down when seating the boolit
2) Swaging the boolit size down when crimping the boolit

As in most cast reloads, slug your barrel and go .001 to .003 over
Pull the first boolit you load and make sure it is still the diameter you want. If it isn't you need to either pre-expand the case neck or crimp less.

I just started shooting 9mm,never owned one before...my gun shoots cast wonderful!!toss up between fast tg.
And slower hs6,,them are my favorites,so far.

I have 3 9mm's, a pistol, a semi auto carbine, and a single shot rifle. All shoot well with 3 to 4.5 grains of Red Dot under a 120 to 158 gr cast. Mostly I use a .38 special bullet as it casts just a smidge bigger and 2 of my guns showed keyholing with standard .356 bullets.

.359 cut the keyholing entirely and tightened groups up nicely.

Fast or slow is your call. But for me, make mine Red Dot!

I also use HP-38 and W231-- but with my Walther P1 and P38 seem to get my best results with Titegroup. All use cast bullets

I don't use your powders but red dot works good for me. Find a burn chart that lists both.

I use N320 in the 147 grain loads that go through my Glocks with factory barrels. My casts are sized to .357" after HiTek coating.

At the present I am using N 340 in my 1911 with a 124 grain. It prints good on paper and clean. I do have some N320 and just bought some N350.

Well, I know all about the need for proper boolit fit to the gun, and the risk of sizing down the boolit during the loading seating/crimp process.

This is more about the powders burnrate and gas pressure carecteristics in combination with lead.. if a fast burning powder powder or a slow one is to prefer? In general?

The questions/speculations that came up during the discussion and got me thinking was:

-If a boolit is proper sized but of a soft alloy a fast burning powder will accelerate the boolit to fast and jump the rifling and cause leading, poor accuracy and even tumbling. A slow burning powder would be a better use due to a lower gas pressure and more even acceleration through the barrel and better grip to the rifling.

-A proper sized boolit of a hard alloy can use both slow and fast burning powders. No leading, and accuracy are more of a load development thing.

- A undersized but soft boolit would benefit from a fast burning powder (within limits) due to that the rapid pressure makes the boolit initially expand to fit barrel. A slow burning powder would cause gas blowby and bring the problems that comes with that.

- A undersized hard (to hard) boolit will have gas blowby with both slow and fast powders, and the problems with that.

There are alot of factors, especially with 9mm. Fit and hardness is important, but how will the powder burnrate help or cause any problems?

Your thoughts and experiences on this?

Swede 45, Nice information on the 9mm. Thank you. Do you have a preferred powder and cast boolet weight for the 9mm?

Tigweldit: No, I've had so much problems with 9mm in the past. To the point where I gave up on the caliber. Now I'll give it a try again and tries to gather as much information and knowledge as possible to save me from the same problems all over again.
These are just thoughts, not truths, that came up with a friend that has the same bad experience of lead in 9mm as me..

The question is:
If all other factors are the same: proper size, adequate lube, alloy hardness, velocity, boolit weight and so on.. Is then a fast or slow powder to prefer?

Swede,
That is probably the best written, most concise observation I have read on he subject...
THANK YOU

95% of my 9mm loads are loaded with a fast powder. I'm using Clean Shot.

The other 5% are loaded with RamShot Competition...another fast powder.

Are Vithavouri powders the only available? Alliant Power Pistol and Red Dot are fantastic, covering the full power range. With power pistol and miha cast 125 hollow points/eastwood clear powder coat I have made excellent full power target ammo. With red dot and 125 grain commercial hi tek bullets I loaded them to barely cycle the gun so the brass would fall into a tools bag beside my right foot. It really depends what exactly you are trying to do, with what is available to you.

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Think about this
The shorter the barrel the faster the powder needs to be
You need to get enough energy transfer to the slide to ensure proper
Function
I like the idea of a hard sharp slap as opposed to a long slow push
So I go with Bullseye plus i get a lot more rounds per pound

I am assuming the pistol is recoil operated: a slower burning gun powder requires a heavier charge to maintain the same pressure as a lesser charge mass of a faster burning gun powder.
Recoil is the total force of acceleration of the projectile and acceleration of powder gasses.
The equal and opposing force you feel in your hand when the gun fires.
I have never used bulleye, I understand it has application very similar to red dot.
If we load two different 124 grain hollowpoints to 1050 feet per second, one with power pistol, and the other with bullseye, which one do you think will more positively cycle the gun?

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Im about 550 rounds into a load work up,on a new 9mm,,accuracy seems to favor the slower burners,,hs6,#7,and unique have been shooting small groups with heavish boolits.

Try all the suitable powders you can and shoots lots of groups. Hardly any firm rules on this.

I like fast powder in my nines . Use bullseye 3.5 to 4 gr with 115 to 124 gr bullets. I have tried slower powder like hs6 and others but it only shot better in my 40 s&w carbine. In my pistole in 40 it doesn’t seem to matter. At 25 yards the carbine liked hs6 loaded on the hot side right below or to max book loads. Maybe I just can’t shoot a pistole accurate enuf to tell the difference but the carbine I can tell. Really haven’t got any leading using fast or slower powders when sized right.