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Pietta New Model Army Revolver - absurd trajectory issues.

Posted: Fri Jul 28, 2017 12:37 pm
by Dark Skies
I have a stainless example that is in (after a full overhaul) exceedingly good shape. Everything that moves in the action has been replaced and it's now super slick and well-timed. The barrel is in lovely condition, after a decent clean, and doesn't seem to have been used much at all. It is completely standard. No trick nipples or anything.
It has the traditional fixed sights - I opted for this over target sights because, well, it's more 'cowboy' - and why not?

I'm shoot it on an indoor range at 20 yards.
My current load is 30 grains by volume of Hodgdon FFFG
I use a lubed Ox-Yoke Wonder Wad on top.
I'm using pure lead balls - these, in fact:
http://www.ebay.co.uk/itm/44-454-Lead-R ... SwYGFUuQii

They really are very round - better than I've bought from specialists in fact. Those always seem to have a flat on them from the mold. They weigh, on average, 137.2 grains.

I don't use any fillers. I consistently ram the load to the same depth - not hugely compacted as hard as possible but snug.
There is scope for a good deal more powder. I'd say at that loading you could maybe get another ball and a half in there (not very scientific but a good visual image).

My problem is the trajectory is like a banana. It drops considerably over that 20 yards - I would say as much as three foot from the point of aim (although I've not measured it accurately with a tape).

At the moment to get rounds on paper I am aiming at the wooden crossbeam of the ceiling (it's a low roof) sighting through the rear V and directly through the bottom of the front blade. When I say bottom I literally mean the point where the foresight is attached to the barrel.

For various reasons Pyrodex and black powder as propellants are out. I'm stuck with Hodgdon FFFG on this range and there are no realistic options to shoot elsewhere.

The above being the case are others on here shooting the same pistol with the same propellant doing better than this and if so what load are you using?

I'm wondering if 30 grains is sufficient and maybe I ought to crank up the load.

I have a Pietta .36 Colt Navy which doesn't suffer to this extent and I regularly hit the bull with that - so it's not just that I'm a lousy shot. :)

Re: Pietta New Model Army Revolver - absurd trajectory issue

Posted: Fri Jul 28, 2017 1:10 pm
by WelshShooter
It might be down to fit of the ball. Do you get a nice ring of lead shaving when you seat them? I used to use .454 balls and they fit fine, but there were others who would shoot their .44's using .457 balls.

I would trying a cylinder with the use of fillers. You may be seating your balls too deep which could lose some steam by the time they are jumping to the rifling. I used to seat my balls such that they were slightly sub-flush from the face of the cylinder so that it could rotate. A good fitting ball will not jump out from the chamber due to recoil etc. so it shouldn't lock up the action.

What about the sights? I'm assuming you bought this used. Are the rear and front sights the correct ones or have they been altered in any way?

I don't think the load is too much. I used to shoot 24gr (equivalent blackpowder volume) of Pyrodex P powder with the .44 and that didn't have a rainbow trajectory at 25 yards.

Re: Pietta New Model Army Revolver - absurd trajectory issue

Posted: Fri Jul 28, 2017 1:25 pm
by Dark Skies
WelshShooter wrote:It might be down to fit of the ball. Do you get a nice ring of lead shaving when you seat them? I used to use .454 balls and they fit fine, but there were others who would shoot their .44's using .457 balls.

I would trying a cylinder with the use of fillers. You may be seating your balls too deep which could lose some steam by the time they are jumping to the rifling. I used to seat my balls such that they were slightly sub-flush from the face of the cylinder so that it could rotate. A good fitting ball will not jump out from the chamber due to recoil etc. so it shouldn't lock up the action.

What about the sights? I'm assuming you bought this used. Are the rear and front sights the correct ones or have they been altered in any way?

I don't think the load is too much. I used to shoot 24gr (equivalent blackpowder volume) of Pyrodex P powder with the .44 and that didn't have a rainbow trajectory at 25 yards.
The balls are a decent fit. I always get a nice lead ring. I load the cylinder out of the gun using a device I bought from Henry Krank - it takes some decent effort. I think .457 might be a little tight but I've not tried as yet.

Whilst I'm loathe to use a filler (it's just more fiddle-faddle) I'll give it a go and see what happens.

The sights are entirely standard - the rear notch hasn't been messed with and the overly tall foresight blade hasn't been touched either.

I did wonder whether instead of a filler I might try putting in a thicker wad. I've seen a Youtube on the process:

https://www.youtube.com/watch?v=YgNVPC2wmWI&t=4s

I've found a source for the materials and thought 'why not just use thicker wadding'?

Re: Pietta New Model Army Revolver - absurd trajectory issue

Posted: Fri Jul 28, 2017 4:51 pm
by redcat
Are you sure the powder measure is set right? That sounds like an awful lot of space in front of the ball for that amount of powder.

Redcat

Re: Pietta New Model Army Revolver - absurd trajectory issue

Posted: Fri Jul 28, 2017 5:23 pm
by 1066
I can't see this as a trajectory problem - with that charge and a good fitting ball you should be getting, at a guess 900 fps. The actual drop is just an inch or so at 20 yards.

Something else is amiss. Did you have a new chamber when the pistol was rebuilt? ie. Although the balls are a good fit in the chamber with a ring of lead being shaved off, does this make them too small for the barrel? Need to slug the bore.

Your powder has absorbed moisture or degraded in some other way? Your caps are weak and not igniting your powder well? Your barrel is badly fitted/bent?

Get someone else to shoot it - try different powder, preferably proper black powder.

Re: Pietta New Model Army Revolver - absurd trajectory issue

Posted: Fri Jul 28, 2017 7:02 pm
by Dark Skies
redcat wrote:Are you sure the powder measure is set right? That sounds like an awful lot of space in front of the ball for that amount of powder.

Redcat
I'm pretty sure. I AM sure. But I'll check regardless.
I'll make a point of physically measuring the gap using the depth gauge of a set of Verniers too - for a more accurate assessment.
1066 wrote:I can't see this as a trajectory problem - with that charge and a good fitting ball you should be getting, at a guess 900 fps. The actual drop is just an inch or so at 20 yards.

Something else is amiss. Did you have a new chamber when the pistol was rebuilt? ie. Although the balls are a good fit in the chamber with a ring of lead being shaved off, does this make them too small for the barrel? Need to slug the bore.

Your powder has absorbed moisture or degraded in some other way? Your caps are weak and not igniting your powder well? Your barrel is badly fitted/bent?

Get someone else to shoot it - try different powder, preferably proper black powder.
As far as I am aware the chamber is the original - but I did buy it secondhand so can't be 100%

Pretty sure the powder is pretty good. It had to be ordered in so it was fresh to me a few months back. In any event I've used it in my .36 and that's shooting well.

Caps are new too - CCI #11

The barrel appears to be fine - I think I'd notice - I have an almost Rain Man eye for things like that. I have natural plumb and am a keen, and quite possibly annoying, picture-straightener. :)

I'll definitely give slugging the bore a shot. I'll also get one of the better BP shooters at my club to put a few through it and see if they fare better.

Cheers for the input all.

Re: Pietta New Model Army Revolver - absurd trajectory issue

Posted: Fri Jul 28, 2017 7:04 pm
by channel12
I've never anything other than black powder in my Remington pistol. I use 24g of either fine or medium which approximately 1.6 cc using a Lee scoop measure. What volume does your 30g of hodgdon give?

Re: Pietta New Model Army Revolver - absurd trajectory issue

Posted: Fri Jul 28, 2017 7:13 pm
by Dark Skies
channel12 wrote:I've never anything other than black powder in my Remington pistol. I use 24g of either fine or medium which approximately 1.6 cc using a Lee scoop measure. What volume does your 30g of hodgdon give?
I'm probably misunderstanding you - my powder measure is marked in grains by volume. So I'm hoping 30 grains by volume is accurate. It's one of those simple sliding tube measures with a knurled locking nut.

Re: Pietta New Model Army Revolver - absurd trajectory issue

Posted: Fri Jul 28, 2017 7:21 pm
by channel12
Dark Skies wrote:
channel12 wrote:I've never anything other than black powder in my Remington pistol. I use 24g of either fine or medium which approximately 1.6 cc using a Lee scoop measure. What volume does your 30g of hodgdon give?
I'm probably misunderstanding you - my powder measure is marked in grains by volume. So I'm hoping 30 grains by volume is accurate. It's one of those simple sliding tube measures with a knurled locking nut.
It sounds like you doing correctly, measuring by equivalent volume of bp. 30g of black powder would give you plenty of bang and velocity.

Re: Pietta New Model Army Revolver - absurd trajectory issue

Posted: Fri Jul 28, 2017 9:11 pm
by Hrun
I use 21 grains of Pyrodex FFG, a thick wad and ball in an 1858, and there is no way I could fit another ball and a half in.

Sounds to me and my limited experience your load is light?