Walker Range Day

[Legionnaire]

Finally had an opportunity to get to the range with my Walker today. Great fun. I shot nine cylinders of Hornady .454 balls in front of a lubed wad, over the following loads (grains) of Goex FFFg in the following sequence: 35, 40, 45, 50, 55, 35, 40, 45, 50. I ran a bore brush through the barrel and chambers after each cylinder. I was shooting over a chronograph, and when I get my notes sorted, I'll post results. From memory, seems like 45-50 grains was the sweet spot.

Unfortunately, my loading lever latch broke. But I had some pipe cleaners along, and used one of them to hold the loading lever in place. Is this part particularly susceptible to breakage?

A lesson learned was don't leave parts soaking and go away for a couple of hours. Had to leave for a wedding before finishing cleanup, and it was a pain finishing when I got back. It would have been better just to let the gun sit until I got home from the wedding before starting on it. Still, a great day at the range.

 

[Legionnaire]

Data

Finally have some time to get back to the computer. Data from the range day. I had loaded the gun 10 days previously, but had not capped. It showed dramatically in the data; velocity was way off on the first string. Data listed as:

String, Grains, Average (fps), Spread, Std Dev.
1, 35, 700, 210, 76.9
2, 40, 1100, 39.81, 16.0
3, 45, 1125, 61.68, 26.2
4, 50, 1173, 57.87, 23.6
5, 55, 1188, 81.14, 28.9
6, 35, 1019, 36.44, 13.5
7, 40, 1082, 63.90, 22.9
8, 45, 1134, 68.59, 28.6
9, 50, 1156, 46.81, 17.6

I would have liked to shoot one more cylinder at 55 grains, but ran out of time. Interesting to see how the original 35 grain charge, which sat uncapped for over a week was off by 300 fps compared to the fresh charge. Also interesting to see that it appears that the velocity increase from 50 to 55 grains is insignificant, suggesting there is nothing to be gained by going over 50 ... at least in this gun.

Now just need to order a new loading lever latch. Guess next test will be with one of the Dragoons ... or a Ruger Old Army.

 

[Tomahawk674]

Thank you for the information!

It always seems to me that the first cylinder through my black powder revolver is "weak", and I this is a freshly loaded charge, not one that has sat there for any ammount of time. Perhaps the residual oil still manages to affect the powder charge...

 

[Pulp]

Your numbers are higher than mine. With a 42 grain load I had a few just under and a few just over 1000fps. It's odd how each gun can give different results. It sure would be boring if they were all exactly the same.

 

[mykeal]

interesting to see that it appears that the velocity increase from 50 to 55 grains is insignificant, suggesting there is nothing to be gained by going over 50 ... at least in this gun.

???
You don't have the data.

Your numbers are higher than mine...It's odd how each gun can give different results.

Or each chronograph.

 

[Legionnaire]

mykeal is right, of course; insufficient data. So back to the range today. Chronograph at three yards from muzzle, just like last week.

Here's the table of results across both outings; it was 10 degrees warmer today, and I also dropped the first 35 grain string from the table above, reshooting two new cylinders at 35 grains. The data from today's outing are in blue, and the aggregate (AG) data for each charge weight are shown in red (calculated across all 18 individual shots). "String" is the order in which the cylinder was shot across the two days of data. And I rounded the spread for convenience:

String, Grains, Average (fps), Spread, Std Dev.
1, 35, 700, 210, 76.9 (excluded from aggregate data)

6, 35, 1019, 36, 13.5
10, 35, 1009, 51, 18.6
11, 35, 1034, 53, 22.5
AG 35, 1021, 91, 20.5

2, 40, 1100, 40, 16.0
7, 40, 1082, 64, 22.9
12, 40, 1077, 75, 27.1
AG 40, 1086, 76, 23.4

3, 45, 1125, 62, 26.2
8, 45, 1134, 69, 28.6
13, 45, 1132, 56, 18.6
AG 45, 1132, 77, 23.7

4, 50, 1173, 58, 23.6
9, 50, 1156, 47, 17.6
14, 50, 1163, 44, 14.6
AG 50, 1164, 70, 19.2

5, 55, 1188, 81, 28.9
15, 55, 1196, 60, 22.4
16, 55, 1161, 71, 26.8
AG 55, 1181, 91, 28.9

17, 60, 1271, 28, 11.0
18, 60, 1308, 53, 21.2
19, 60, 1313, 39, 16.6
AG 60, 1298, 73, 24.9

I was not able to fit a wad into the cylinder with the 60 grain loads; they were fired with a ball directly on top of the powder, and the cylinder mouth then covered with T/C Bore Butter.

Interestingly, the average velocity gains with loads that included a wad were as follows:

35 to 40 grains = 65 fps
40 to 45 grains = 46 fps
45 to 50 grains = 32 fps
50 to 55 grains = 17 fps

However, the velocity gain from 55 to 60 grains loading the ball directly on top of the powder and then sealing the cylinder with Bore Butter ...

55 to 60 grains = 117 fps!

Looks like I have more experimenting to do!

 

[mykeal]

Good stuff.

And, you're having fun!

 

[Legionnaire]

Roger that! I've not been using filler, and probably should. Next time I play with the Walker, I think I'll skip the wads and use a filler to keep the ball seating depth more consistent, and seal with grease. I'm amazed at the velocity increase at 60 grains above, and I'd like to see how filler and grease compares with the lubed wads.

 

[Tomahawk674]

Does anyone else have feedback on the first cylinder of shooting being weak?

Kind of bad considering back in the day when these guns were being used, you'd only be shooting the 6 shots and most likely not reloading...

 

[Legionnaire]

I think "back in the day" I'd have only loaded five and capped them. I'm guessing recent humidity and open nipples contributed to my weak first cylinder results. I'm also guessing that "back in the day" a trooper would have reloaded his guns on the morning of a battle. They didn't tend to sneak up on folks.

 

[Tomahawk674]

My point is, my first cylinder is weak even when loading right before firing. Maybe it's the oil, because I don't snap caps on all the nipples before firing like some people do, due mostly to the cost of caps.

 

[Legionnaire]

I understand. I'll have to watch for that. In the second table of data above, string 10 at 35 grains was the first of the day; it does appear to be slightly down from string 6 and 11, neither of which were "firsts." I don't always take the chronograph along, though. I did snap a cap on each cylinder before loading for record.

 

[mykeal]

You might repeat part of the first series of tests before changing load parameters to see if the increases between 45, 50, 55 and 60 repeat themselves. Any time you get an empirical result that doesn't follow the trend, suspect the the method, not the theory.

 

[Legionnaire]

mykeal (or others), do you have a theory as to why I'd see such a dramatic velocity increase from 55 to 60 grains? Up to 55, the return on each 5-grain increment was declining ... then a 100+ fps gain?

The obvious changes were two: greased cylinder mouth instead of a lubed wad (i.e., lube in front of the ball rather than behind it), and ball set closer to the cylinder mouth. A third possible variable would be a more compressed load, as I really had to work the loading lever to get the ball set without protruding from the chamber mouth. A fourth possible variable might be that I worked loads UP; wonder what would happen if I started with 60 grains and then moved down the ladder.

I love testing theories ... it's just that in this case, the theory isn't obvious to me.

 

[junkman_01]

I'd chalk it up to an inaccurate chronograph reading.

 

[mykeal]

junkman01 - You must mean 3 inaccurate chronograph readings.

Legionnaire - No theory yet. The readings don't make sense. You need to see if you can repeat them first.

 

[junkman_01]

Sure for the 60 grain loads. How far is the start screen from the muzzle? It could be that the increased flash is tricking the chrono. Try setting the screens further away and repeat a few of your velocity tests and see if they now follow the trend. Shooting BP guns over sky screens presents some unique problems not found with smokless powder guns.

BTW, A ballistic pendelum would not have these problems and it is how projectile velocities were measured befor the advent of electronics....

CLICK HERE

 

[Pulp]

Three yards from the muzzle may be too close. You may be reading smoke or unburned powder. I did mine from about 10 yards from the muzzle.

 

[Legionnaire]

Hmmm. I guess proximity to the chronograph could come into play. 10 yards seems "way out there," though. I've regularly shot centerfires at three yards with no apparent adverse effects ... interesting thought.

Here's another: Could the wad following the ball be messing with the chronograph? I just assumed the first projectile through the sky screens would be read. I know the wad is flying downrange, too. It marked the target a couple of times. Talk about a "duh" moment ...

 

[mykeal]

Uh, yes, 10 yards is too close for bp guns, and the wad is certainly a factor.

 

[junkman_01]

I thought the screen distance could be the problem. It wouldn't be the first time.

 

[Legionnaire]

Interesting. I have a Shooting Chrony Alpha Master. The manual states that three meters or ten feet is fine for high powered rifles, and suggests that other firearms can be shot closer. It recommends five feet for shotguns so as to avoid the pattern or wad hitting either the unit or the screens. It talks about how to protect the unit from muzzleloader debris, but makes no suggestion of moving it out beyond three meters.

http://www.shootingchrony.com/manual_ASC&AMC.htm