Maximum combination of propellant & projectile for Investarms muzzleloading firearm

[cgoding]

My manual states that my .54 flintlock has a maximum either .530 RB or 405 grain maxi ball.
I have 430 grain .54 caliber maxi balls
Should I shoot them anyways?

 

[Phil Coffins]

Yes.

 

[Marc H]

I would use the information, as written, in the owner's manual.

Marc

 

[justinoldguy]

My manual states that my .54 flintlock has a maximum either .530 RB or 405 grain maxi ball.
I have 430 grain .54 caliber maxi balls
Should I shoot them anyways?

Yes, your rifle will safely handle any conical within reason. However, Safe and Best are often two different things. I've been shooting muzzleloaders for 50 plus years, and I have found PRB's to be the projectile I prefer by a large margin. When I was young, I got caught up in ballistics charts and ft.lbs of energy, and wanted the most "powerful" load. Now that I am older, and hopefully wiser, I have found that moderate loads are a far better option.

 

[tenngun]

You gun can more then handle the bigger conical. Provided it’s seated well you could run two of those and a double charge and only your shoulder or the guns wrist would suffer
Howsomever all ml are short ranged weapons for quick clean kills. You will find moderate accurate charges behind a ball to be an effective killer in ml ranges
I used to ‘load for bear’ but found out over the years it was just a waste of powder.
A .54 ball on a hundred grains of three f will make two holes in an elk at a hundred yards

 

[French Colonial]

I do not shoot conicals but in modern guns the stability of the bullet is dependent on length of the bullet and twist rate.

The heavier the bullet for a given caliber, the longer it is and the faster the twist needs to be to stabilize it.

Does going from a 405 grain to a 430 make a difference here?

 

[tenngun]

I do not shoot conicals but in modern guns the stability of the bullet is dependent on length of the bullet and twist rate.

The heavier the bullet for a given caliber, the longer it is and the faster the twist needs to be to stabilize it.

Does going from a 405 grain to a 430 make a difference here?

You would have to shoot to find out. TC made its maxie ball in .54 , I think it was 430, and it stabilized in 1/48 round ball barrel.
Today most RB rifles are slower twists 1/66 is common. I had a green river barrel in 1/66 and got hunting groups at one hundred yards with a maxi, I never hunted with it just ran a box to see.

 

[dave951]

Remember that the manuals were edited by lawyers. That said, keep it sane and don't get caught up in chasing "max" loads and you'll be fine. Accuracy and bullet placement is what gets game, not bullet speed and near misses. If the bullet is accurate at a moderate load, you'll be fine.

 

[nkbj]

My manual states that my .54 flintlock has a maximum either .530 RB or 405 grain maxi ball.
I have 430 grain .54 caliber maxi balls
Should I shoot them anyways?

Just out of curiosity, what does the manual say is the maximum powder charge with a 405 grain maxi?

 

[tenngun]

People often get caught up in the enemic power of an ml. It’s low velocity and low fp
Modren guns need high speed to get expansion and this energy transfer to the target. And keep that velocity down range
A .50 is already bigger then a modern bullet fully expanded, and the soft lead is excellent at transferring power to the target, in its much decreased range
One of the toughest lessons to learn is stay in range, concentrate on shot placement and throw the ballistic book away.
Get close, get your shot and get meat on the table

 

[nkbj]

Cogoding,
The Investarms probably has a 48" twist which in a .54 bore is not a "slow" twist at all and will likely shoot the 430 grain bullets just fine.

Passing thoughts... in working up your loads the best accuracy for target work or hunting will likely be found at some point less than a maximum charge of powder so again, I'd say not to worry.