Filler Question.

[tacfoley]

Conventional wisdom suggests that we should use a filler in our muzzle loading revolver loads for two reasons.

1. To eliminate an air gap in the chamber which might result in an inconsistent burn rate.

2. To place the projectile closer to the breech thus allowing it to engage the rifling without a jump if it were to be seated deeper within the chamber.

My question takes us back to the time before the breech loading handgun ban in 1995 when smokeless powder was the most common propellant. Back then, the standard .38 Special revolver target load was around 2.8 grains of Bullseye behind a 148 grain Wadcutter lead bullet. The tiny amount of powder would have left a huge air gap in the .38 Special cartridge case and the Wadcutter bullet itself would have been completely seated within the case resulting in quite a big jump before the bullet entered the rifling. So, why is the use of a filler considered essential when using black powder loads, but doesn't seem to be necessary when using smokeless powder ?

Regards
Brian

It's because BP is an explosive compound, and the air contained in the space would enable an 'explosive front' to generate, causing, mostly, massive damage in a confined space such as bulging of a chamber, or bulging/ringing of an barrel - or at it worst, a burst barrel.

By contrast, nitro propellant compounds do not detonate, but burn, albeit quickly, as far as WE are concerned, but slowly as far a actual physics are concerned.

[Abasmajor]

It's because BP is an explosive compound, and the air contained in the space would enable an 'explosive front' to generate, causing, mostly, massive damage in a confined space such as bulging of a chamber, or bulging/ringing of an barrel - or at it worst, a burst barrel.

By contrast, nitro propellant compounds do not detonate, but burn, albeit quickly, as far as WE are concerned, but slowly as far a actual physics are concerned.

Thanks for the reply. I can understand the possibility of an explosive compound detonating in a contained air environment causing a problem, but wondered if the same situation would arise when using a black powder substitute such as Pyrodex or 777 which are classed as propellants rather than explosive compounds.

Do you believe in practice that not seating the projectile really close to the rifling would have a detrimental effect on accuracy ?

Brian

[loiner1965]

greener and others say an air gap in brass cased ammo is possible if 80% of capacity is used.
i know a few shooters who use no filler at all just 85 gn of bp in a .577 / 450 with usual wads etc in the neck.

[enfield2band]

I don't use a filler in my repro revolver. I use 22 grains of fine blackpowder and it is accurate enough at 25 yards even though the ball is away from the rifling.
If I fill the chamber up with powder so the ball sits close to the rifling the accuracy is abysmal.

I don't know if a filler improves accuracy.I find that lower charges are better in most revolvers.

It may be that the ball has chance to stabilise at short range with the lower charge.

[Fronteria]

I dont use anything other than blackpowder to fill chambers in my Colt Walker just 55 grains of black powder a .44 wonder wad and a .457 ball.
In my flintlock .520 all steel Scottish pistol I use 40 grains of black powder a 10 thou lubricated patch and a .500 ball.
Most satifactory and enjoyable to use.
If you buy a replica at least use an original load in it.