Testing The .40

[hanshi]

I recently chronographed my .40 and thought it might be interesting to post the results.

38" barrel, Goex 3F, .390" ball, .020" patches lubed with Hoppes, felt op wad, measure thrown charges, screens set 15 feet from muzzle.

CHARGE                AVERAGE VEL.                   SD                        COMMENTS
____________________________________________________________________

30 grns                    1371 fps                      20

35 grns                    1449 fps                      18

40 grns                    1678 fps                      5                          (favorite)

60 grns                    1848 fps                     17                         (favorite)

65 grns                    1920 fps                     20                         (fast)

[northmn]

Interesting results.  Seeing the difference that only 5 grains makes causes me to wondere if I should not use a smaller diameter powder measure. 

DP

[caliber45]

Hanshi -- When you're through testing for velocity, and want to do some accuracy work, try a .400 ball, .20 patch and 55 grains of 2F Goex. Works great for me. -- paulallen, tucson az

[Dew]

Hanshi, I was wondering what barrel you have? I'm building a .40 with a  36 in. green mountain on it. Just wondering for a comparison. Any one of those loads more acurate than another? Thanks, Dew

[hanshi]

My barrel is a 38" , GM "B" weight swamped.  I've been considering getting a .395" mold to try.  I'd expect velocity to be a shade higher with the larger ball.  A .400" ball would possibly be much harder to load than I'd be comfortable with.

Average velocity increase was 78 fps for each 5 grains increase in powder which is not bad at all, the largest (229fps) when going from 35 grns to 40 grns; just an increase of 5 grains.

Not surprisingly, both the 40 grn charge and the 60 grn charge are both very accurate.  Except for 30 grns, none of the others was tested for accuracy.  30 grns did well at 25 yards but was not fired at any further distances.

[Daryl]

tks hanshi - my 42" .40, with a .398" ball, I think it was, and .022" denim patch, lubed with LHV made 2,240fps, or thereabouts with 65.0gr. 3F GOEX. With 75gr. GOEX 2F, that speed was virtually identical as-was the accuracy.  48" twist, Goodeoin barrel.

I might have been using a .400" ball with .020" patch. with a nicely smoothed crown, I find the .400's load virtually the same as the smaller ball with thicker patch.

This is the crown on the .40. To the actual top of the lands, is amost 1/4" down into the bore- a very short cone.  The balls and patch form/draw/swage together quite easily, with never tearing the patch.  I can actually shove the patched ball into the muzzle, with hand pressue alone on the knob of my starter - the pure lead ball swages that easily with this shape.
Since this picture was made, I've shortened the barrel to 36" & put it on a 1/2 stock.  I recrowned it, similar, but not quite  as deeply coned - just 3/16" from, larger than groove diameter, out to the tops of the lands.  It loads identically, if not a tich easier yet than the longer cone. As before, the barrel will still give me 1/2" groups at 50 yards, with this load.

[Leatherbelly]

  Hanshi,
    Until recently I owned a forty. My pet load in a 38" by 48"twist straight Rice barrel was 50gr.of 2f,22 thou denim, .395 RB, and a wwwasher mix with neetsfoot oil lube. Try it if you run out of 3f. I got much the same results as you did with 40 gr of 3f. Very accurate,no wiping. BTW, this barrel was coned but I still used a shortstarter.I like a S/S 'cause it helps get the ball past the rifling without tearing the patch. Maybe that's a falicy but I can't knock the accuracy this wonderful little rifle has. Love those little forties!

[hanshi]

Daryl, I have a .50 with a crown that looks like the one pictured and it loads quite nicely.  My .40 has not been modified but loads easily with the .390" x .020" combo.  I'm anxious to try a .395" ball.

CanvasBack, the 40 grn load has been my standard load for some time, now.  It has been an accurate and economical everyday load.  My barrel is 1-48" also.

As an aside, while chronographing my .36, another flint shooter was there with a very nice self-built .40 rifle.  He fired a few rounds across the skyscreens with his rifle.  His barrel was either 42" or 44", can't remember, and he was also using a .395 ball.   His load of 50 grns 3F gave only a bit less velocity than 65 grns in my 4+" shorter barrel and .005" smaller ball.  I would hazard to guess that simply going to a .395 ball would result in a significant velocity increase.

[Daryl]

Taylor used to shoot just over 40gr. in his 44" Kuntz. The powder measure he initially tried, threw about 43gr. IIRC.  He shot that load all winter, 2 winters ago then finally acquiesced to putting it on paper with that 43gr. 3f load at 50yard or beyond - don't remember.  He rarely shoots any other rifle and now uses the much more accurate charge of 65gr. 3F. with his WWWF lube and .395" ball - about a .021" patch.  

[roundball]

The .40cal Lancaster I just picked up has a straight 38" GM square bottom groove barrel...good heft / balance without being nose heavy...be a while before I can shoot it but looking forward to at least the same accuracy I had out of my 32" GM .40cal barrel on a Hawken stock

[David R. Watson]

I have a .40 with a 1:48 twist made by H&H in 1980. I shot a .410 RB with .017 pillow ticking ahead of 60 gr FFF when I was competing...Flintgun with a Bob Roller lock.
Funny thing was that it shot dime size groups at 50 yards, but the highest score i ever fired at 100 yards was a 36 and this was off a bench.
The oversized RB was turned into a jellybean and I don't think the 1:48 could stabilize it at 100 yards. I got out of ML competition and never tried smaller balls and the rifle has been sitting since 1982.
Back then the "shooters" at Friendship were going to space guns and I fell into the same mindset which sort of took away from the whole idea of shooting traditional firearms.

[hanshi]

My .40 has a 1-48" twist, as well.  I would think 100yds would be a cake walk with your load.  Perhaps, as you say, ball distortion is the culprit.  If I were you I'd give .390 and .395 balls a serious try.

[Standing Bear]

Flint and percussion guns Douglas .40 barrels w/ 1/66 twist.  .395 ball .018 patch and 75 gr FFg.  Still good at 100 yds.

[Daryl]

Ineresting, TComp.  My Goodoien .40, has a 48" twist, and with 2F GOEX and an oil patch, it also requires 75gr. of that powder to match what 65gr. delivers in speed and accuracy - both just over 2,200fps.  That was with a .019" pocket drill cloth and a .400" ball.

[Standing Bear]

Never chronoed the percussion (both are 42" barrels) but the flinter was makin an average 2150 fps with the 75 gr of Goex FF.  IIRC the std deviation was 9.

Wind can move a .40 ball but at those speeds, It ain't in the wind for long.