Pietta New Model Army Revolver - absurd trajectory issues.

[dromia]

What is the recoil like with your load?

I suspect that the problem is that stuff you are using as propellant, it is very unpredictable outside the loads that Hodgdon have on their site, go outwith that and you are on your own. If your load is not exactly one of those recommended by Hodgdon, which are not maximum and minimum recommendations, with that stuff then think your self lucky that it is only the trajectory that you have to worry about and not a blown up revolver and the attendant damage to shooters that can cause.

How often does it need to be said never go outside the manufacturers recommended loads and as has been said umpteen times that tripple seven stuff never use any other load than that provided by Hodgdon, it is not black powder it is smokeless powder for use in black powder firearms but has only some of black powder's properties.

If you are using one of the recommended loads and getting that trouble then I still suspect that it is the powder, it very finicky in its performance and variations in chamber dimensions and/or internal shape will effect how it performs.

If you still feel that it is revolver issue then you need to go somewhere that allows real black powder to be used and try it there to sort out whether it is a powder issue.

Even if your revolver had the accuracy curse of chambers with smaller diameters than the bore you still wouldn't get such a drop with any respectable load of black powder, you would struggle to get groups however.

Regardless of the eventual cause(s) of the issue you are having using loads other than those specified by Hodgdon is a high risk approach.

[Dark Skies]

The recoil is negligible - although it's a weighty gun to begin with it's certainly nothing like this:
https://youtu.be/-lb8E3qQVKY?t=86

I think I'm right on the upper recommended limit - a lot of settling goes on if I flick the side of the powder measure.

I took it to the range last night and put a few balls down range with the lower limit with little change.

HOWEVER, I did notice that on four of the shaved rings on ramming the ball home they tended to break on one side. I haven't as yet measured this but my current thinking is that the balls I'm using ( .454 that are actually .450 ) may be a smidgen too small and the broken rings may be indicating this. I've ordered some .457 balls to see if I get a regular, reliable, unbroken ring of lead to see if matters improve.

[tackb]

I'm with sim g , your accuracy is good just in the wrong place , I'm going to go with a revolver issue rather than load. It's accurate but putting the group in the wrong place which is sights

[The Lord Flashheart]

I'm not altogether convinced, as Sim G asserts, that my load is already 5 gr x volume over the manufacturer's recommendation. If I give a slight tap of the measure when filled the powder settles by almost 5 gr - so it may be more accurate that I am right on the limit of Hodgdon's chart.
Having said that I'll try dropping the charge by 5 gr x volume and see if it has any affect one way or t'other - it may be that there's no noticeable difference in which case at least I can squeeze more bangs per tub of propellant.

Sim G is correct. If you check the data sheet https://www.hodgdon.com/wp-content/uplo ... l_2008.pdf they give just two loads for your revolver, 20gn and 25gn. I'm sure their site used to have a warning about deviating from the stated load and to avoid any filler with Triple 7, but I can't find that on their site now so maybe things have changed.

Using a .457 ball will just shave more off, as ramming it into the cylinder effectively sizes it to the cylinder's diameter.

I'd suggest trying a Pyrodex P or BP load of the volume which others have stated, with either a wad or filler so that you lightly compress the charge when seating the ball. I prefer to seat the ball just below the cylinder so as not to foul when it is rotated. I know others who seat it deeper and it still works. There is no need to ram it in as tightly as possible. From what you said earlier about fitting an extra ball and a half in, perhaps you are compressing the powder way too much. I don't know if this would generate the results you are seeing. I have found a 15gn BP or Pyrodex load shoots as accurately as 20-30gn at 25 yds. More powder gives a different point of impact with more smoke and a bigger bang but no better accuracy.

I know people who shoot cap and ball revolvers well past the first flush of youth and don't get a crazy trajectory. I think your load or loading is the issue rather than a fault with the gun.

Good luck with getting this sorted

Donald

A BP newbie here, just going about acquiring his first pistol...

I have seen the Hogdon Load data you mentioned and was wondering whether the 20-25 grain load data given is a range rather than an either/or situation whereby only 20 and 25 grain loads are recommended?

[dromia]

Nowhere on the Hodgdon data does it say maximum or minimum loadings.

It has only two loads recommended for that awful stuff 20 gns and 25 gns by volume, not by weight!

Load outwith this at your peril.

[The Lord Flashheart]

Nowhere on the Hodgdon data does it say maximum or minimum loadings.

It has only two loads recommended for that awful stuff 20 gns and 25 gns by volume, not by weight!

Load outwith this at your peril.

It doesn't but then again it doesn't make a point of specifically mentioning that it is not a range, as powder manufacturers seem to go out of their way to do with everything else.

For example, the published load data for the various rifle cartridges that use H4895 do not list the full range of charges on the lower end that elsewhere Hogdon says may be reduced by up to 40% for reduced and youth loads in perfect safety.

Hence I was wondering what the reason might be for a 20 grain load being safe, a 21 grain load unsafe, ditto until 25 which is then safe again?

[Dark Skies]

Nowhere on the Hodgdon data does it say maximum or minimum loadings.

It has only two loads recommended for that awful stuff 20 gns and 25 gns by volume, not by weight!

Load outwith this at your peril.

Surely, if it has only two stated measures, then 20 grns X volume is the lower limit and 25grns X volume is the upper limit?
That's just logic, surely?

If I had my way I'd ditch the powder and ball altogether and get one of those .45 cylinder conversions from the States that allows me to shoot modern .45 cartridges through it - but I can't because the law forbids it.

So it is with Hodgdon I'd love to shoot with black powder on our range - I really would but I can't because our club forbids it and nowhere within practical distance presents an alternative as yet. It really isn't helpful to be told how crap smokeless alternative powders are - s'truth, I have to drive 100 miles round trip just to get that.

[The Lord Flashheart]

Apologies for the thread hijack Dark Skies...

[dromia]

You don't have to believe me, it is your hands and face, worse still it might be someone elses.

Twist the "logic" any way you want but that is not what it says.

I don't know how many times on here I have warned about Tripple 7's propensity to dangerously pressure spike when loaded outwith the data, but as I obviously cannot be believed I will leave it to you to do as you will. Last time I bother offering you advice.

[The Lord Flashheart]

Erm...

I was hoping to pick your brains for knowledge, not engender feelings of being unloved.

I was wondering if there was some arcane explanation for what seems a counterintive situation rather than hoping to blow my face off, if you see what I mean?