Chronograph Data: Elmer Keith style vs Lee Tumble Lube 148 grain Wadcutter velocity.

Today I shot again the 148 grain Lee Tumble Lube Wadcutter over the cronograph but this time with an different powder.
This time I used the O***a powder (scavenged from shotshell) which is the quickest burning I have as I believe.

First shot I used an 0.5 cc Lee powder dipper which I levelled off the powder and that gave exactly 3.6 grains. The Chrono APP did not work again but it gave me an velocity of 987 fps using 3.6 grain of the O***a powder with the deep seated 148 grain Lee TL Wadcutter.
That gives an energy of 320 ft/lbs.
With this powder load no particularly flattened primer nor sticky extraction was observed (primer was round on all edges).

Second reload was with an heaped full 0.5 cc Lee powder dipper (no levelling/scraping off powder) and that gave exactly 4.0 grain of powder. Same bullet as above that gives an energy of 351 ft/lbs.
This time the Caldwell APP worked and here is the result:
Created: 14-02-2017 12:40:32 PM Description: 148 grain Lee Tumble Lube DE Wadcutter Notes 1: 4.0 grain scavenged powder brand O***a Notes 2: Pietta 357 mag SAA 5.5“ revolver Distance to Chrono (FT): 6.00 Ballistic Coefficient: 0.072 Bullet Weight (gr): 148.000 Altitude (FT): 400.0 Temp: N/A BP: N/A Shots # FPS FT-LBS PF 1 1034 351.41 153.03 Average: 0.00 StdDev: 0.00 Min: 1034 Max: 1034 Spread: 0 True MV: 0.00 Shots/sec: 0.00 Group Size (IN): 0.00
Click to expand...
The primer flattened this time but no particular sticky extraction could be observed (surprisingly no sticky extraction. Not more as with the Saga, Unique type powder at 4.0 grains). The primer is flat but not flatter as with the other loads and the case at extraction is only snug to the chamber and not approaching sticky extraction.
But any hotter I would not want to load this System (cartridge-gun System) since 351 ft/lbs is plenty of energy.

Observation: I have an Feeling as if the Lee Tumble Lube design works wonders in reducing the case pressure. I believe this quick burning load I would not want to risk with the Elmer Keith style Lee 148 grain Wadcutter. The TL design gives a slightly edge on velocity but I feel it does a great Job on reducing pressures of the cartridge and reducing recoil as well.

I wonder if the increase in velocity from 987 fps to 1034 fps is already an deminishing return for the 0.4 grain of powder increase (difference)!
 
Last edited:
A few calculations of DIMINISHING RETURNS

Diminishing returns calculations:

Bullet: Lee Tumble Lube 148 grain Wadcutter and O***a scavenged shotgun powder.

148 grain Wadcutter Lee lead .358" ELMER KEITH STYLE bullet loaded with O***a 3.0 grain scavenged powder gives 836 fps of velocity. 230 ft/lbs
... ...
151 fps difference/ 6/10th grain difference = 25.16 fps/0.1 grain in powder increase.
... ...
148 grain Wadcutter Lee lead .358" TUMBLE LUBE bullet loaded with O***a 3.6 grain scavenged powder gives 987 fps of velocity. 320 ft/lbs
... ...
47 fps difference/ 4/10th grain difference = 11.75 fps/0.1 grain in powder increase.
... ...
148 grain Wadcutter Lee lead .358" TUMBLE LUBE bullet loaded with O***a 4.0 grain scavenged powder gives 1034 fps of velocity. 351 ft/lbs

The optimum may lay anywhere between 3.6 grain and 4.0 grain O***a powder.

Can someone check my calculations if they are correct?
 
Last edited:
I loaded one more round with the 148 DE Wadcutter TL and this time

I tapped the 0.5 cc Lee dipper 4 times after filling to settle the powder and then refilled it till full and scraped/levelled it off.

Like that I get an consistent 3.8 to 3.9 grain Charge. Tapping 4 times Kind of gets me 3.9 grains and tapping 3 times tends to get me an 3.8 grain Charge after levelling off the powder.

I chronographed again that 3.9 grain Charge but got only 975 fps (312 ft/lbs) which is even lower than the 3.6 grain Charge from before.
I realised I changed some things which may explain the drop in velocity:
The powder got mixed a bit with the S**a brand (which is a slower powder).
and
And the case I loaded up I changed (for before tests I used the same case over and over) using before Federal (high velocities) and now Winchester (drop in velocity).

That Shows different brand cases may give different velocities differentiating as much as 50 fps.
So there are too much variables changed to validate the 3.9 grain powder Charge test as sample.

I realised according to the Lee powder dipper Chart this O***a powder is of similar bulk Volumen than IMR 700X (that Shows 3.7 grain with the .5 cc Lee dipper and this my scavenged powder gets levelled off without tapping 3.6 grains).
 
It looked from your post #21 that you only have data for one shot of each powder charge. It's pretty normal, taking pressure readings, to see a 10% spread in peak pressure and several tens of feet per second in spread. So if random velocity differences worked against you, the diminishing return might not be real. Take ten shots at each load and find the average (mean) velocity for each, then you can tell from that if the return is diminishing. If it is, that is usually not because the powder isn't doing its job, but because the chamber or frame is starting to exhibit some elastic stretch the pressure, and is a sign your pressure is getting too high for the gun. If that's the case (and it could be with fast powder in a small space), then you want to use about 5% less powder than the 4 grain load, or not more than 3.8 grains.
 
Yes each sample of powder Charge consists of 1 shot due to reloading supplies scarecity.

All those shots are cold Barrel shots.

As I understand you there may not be present diminishing Returns. Further I understand you Diminishing Returns are associated with Overpressure.

Overpressure I judge by the flat primer, sticky extraction and bulges of the case solely.
Before this Experiment I loaded 9mm Luger cases with the 115 grain FMJ to 4.4 grain of any of the powder. This 38 spl has similar empty case Volumen (similar/same total powder Volumen + empty airspace Volumen) as do my 9mm Luger have. Thus it has 9mm Luger energy Levels.

Bulges are NOT present. Nor does any of the cases Show an sticky extraction (although they are snug with the chamber). Primers are flat but Show not dangerous Levels of any overpressure whatsoever.
 
Yes I confirm that:

A sample of 20 cases I shot with the Elmer Keith style 148 grain WC loaded to 3.5 grain of powder Show more flattened primers than These Lee Tumble Lube design bullets (same 148 grain weight WC) loaded to 4.0 grain of powder.
The last shot 975 fps velocity TL bullet almost Shows no flattened primer.

Definetelly the Tumble Lube design reduces pressure while maintaining velocities.

My Explanation of the above:
Both Ends of the Lee Tumble Lube WC design measure about .360" of Diameter and on These the bullet is riding in the Barrel. While the TL groove area measures .355" which is therefore NOT in contact with the Barrel but full of lube.
 
Typically, velocities scatter on a bell curve distribution, which is why one sample at each load level is not enough to tell anything certain. In the worst case, with stretching, velocity may actually go down as powder goes up, and that's a dangerous pressure sign. Another problem is that in production revolvers, the different chambers are not always identical and don't always produce identical pressure. So a sample of at least 6 at each load level will take that into account.

In QuickLOAD I find the powder space you have is either smaller than for a 9 mm with a lead 147 grain bullet, or close to equal. It depends on assumptions. One way to clear that up is to load a TL bullet into a case that has been resized, but that has no primer or powder. Seat it deeply the way you have been doing. Then weigh it and record the weight. Then use a glue dispenser or a hypodermic syringe and needle to inject water in through the flash hole at the bottom of the primer pocket. You want to go slowly and tap it on the side a few times as you fill it to dislodge any trapped air bubbles you may have. Stop when the water has come to the flash hole. Do not fill the primer pocket with water. Weigh the case again with the water in it. If it were typical of a 9mm with 147 grain lead bullet, then it should be around 7.5 grains heavier. If the added weight is less than that, then you are probably getting higher pressures than a 9mm is, as you should reduce the seating depth until you have room for at least 7.5 grains of water behind the bullet.

I may have missed it, but I don't know your barrel length, so it is hard to tell by velocity if you are likely to be going to higher pressures than normal. Primers are not a reliable indicator in revolvers. In some revolvers primers do not get flat until after extraction becomes sticky. In others they are flat all the time. So it is difficult to tell that way.
 
Once I have time I will try the water test.

Meanwhile in my experience primers are not flat at reduced velocities like 840 fps or around 200 ft/lbs of energy with this bullet.
As well according to my experience the Elmer Keith style bullet will have at 250 ft/lbs a flat primer but not so the Tumble Lube design bullet which will have an flat primer if it hits 1000 fps and above (even that flat primer is not very much pronounced).

I observe as well that Blazer brass will flatten the primers out sooner followed by Federal and the least flattened primers used to Show Winchester brass (I do not know if this is an real Observation or just Imagination of myself).

My Barrel length is 5.5" and the Revolver is an Pietta SAA 357 mag Revolver.

May it be as it is my Goal is to get about 350 ft/lbs of energy.
I shot today one of These and they shoot all low to aim (not as accurate as lower power loads). BTW factory (full power) ammo shoots all low to aim in this gun. The ammo has to have power though; what serves it if it has no ooompf!

The seating depth of These reloads is for sure 0.688".
 
The case deprimed, resized and seated with an bullet and without an primer weights 198.9 grain. The bullet is not weighting 148 grain since I drilled a hollow Point into it (it is just this one. The bullets I shoot have all 148 grains) and it is an Elmer Keith style bullet.
The water filled powder space round weights 206.4 grains.

206.4 - 198.9 = 7.5 grains.

I did not clean out the case as I never do. The primer pocket I did clean with the Lyman cleaning tool.
I did not have an TL bullet at Hand since I just recently got the mold and did not make yet much of 'em.
The scale was preadjusted before measuring and I used an Hornady beam scale.
 
Last edited:
Would be glad if Unclenick could extrapolate some pressures, velocities and energies from QUICKLOAD:

These data using an 38 spl case, deep seated 148 grain WC lead bullet to 0.688" (empty powder space water weight is 7.5 grains) and 4.0 grains of VV N330 powder

and

for an 9mm Luger case seated to same depth (powder space water Volumen is 7.5 grain) and the Lee Truncated Cone 124 grain lead bullet. Same powder and charge. As this I load my 9mm Luger rounds and the water Volumen of the powder space is exactly the same in my 9mm Luger and the above 38 spl.
I would appreciate Unclenick if he can run QUICKLOAD for the 9mm Luger with VV N330 for the 124 grain bullet with charges of 3.0/3.1/3.2/3.3/3.4/3.5/3.6/3.7/3.8/3.9 and 4.0 grains
 
Last edited:
New Chrono data and accuracy shooting data

I shot a few more rounds over the Chronograph and put behind an A4 paper at 15 paces (meters) of distance.

Here the Chrono data:
Created: 20-02-2017 12:17:54 PM Description: 148 grain Lee cast Wadcutter Notes 1: Elmer Keith style grease grooves Notes 2: First shot 3.8 grain O***a powder. Second shot 3.9 grain same powder Distance to Chrono (FT): 6.00 Ballistic Coefficient: 0.075 Bullet Weight (gr): 148.000 Altitude (FT): 400.0 Temp: N/A BP: N/A Shots # FPS FT-LBS PF 5 ERROR 2 4 17366 99123.54 2570.17 3 ERROR 2 2 1302 557.18 192.70 1 980 315.67 145.04 Average: 6549.33 StdDev: 9368.89 Min: 980 Max: 17366 Spread: 16386 True MV: 6609.04 Shots/sec: 0.02 Group Size (IN): 0.00
Click to expand...
The first shot was a load of 3.8 grain of O***a powder and over the ELMER KEITH style 148 grain Lee Wadcutter and gave an velocity of 980 fps and 315 ft/lbs of energy.
The second shot was an reload of same bullet but loaded to 3.9 grain of same powder. Reading is most likely incorrect due to Chronograph Placement in plain sunshine.
The third shot was an 3.8 grain load as well but due to sunshine the Chrono did not read.
The fourth reading I actually did not shoot. Don't know what happened and what "ghost" flew through the chrono.
The fift reading is a shot and reload of 3.8 grain same powder. Again I guess due to sunshine the chrono gave an error.

Overall the first shot is correct the rest is not reliable readings.

Accuracy

Here the accuracy of the 4 shots I shot:

attachment.php


I was not particularly aiming at one spot of the A4 paper but roughly on the middle.
The one Flyer is most likely the 3.9 grain stiff load and observe that bullet did not carry much lube with it. This round had a slight tendency to sticky extraction.
The rest extracted without to be sticky but they were snug to the chamber. All had flat primers.
Again I observe Blazer brass has a tendency to flatten extremely the primers and Winchester flattens the least.
3.8 grain of O***a powder may be my accuracy load.

Observe on the A4 sheet paper the blue lube around the entry holes. That is a good sign for me since at exiting the Barrel the bullet still carries a lot of lube with it and does not run out of lube in the Barrel.

The powder I loaded with the 0.5 cc Lee powder dipper. I fill it till full then tap it a few times to settle and refill it. Then I scrape off any excess powder. That method gave me from 6 loads 5 of 3.8 grain powder Charge and 1 had 3.9 grain powder Charge (with this method). So it is very consistant.
 

Attachments

  • Elmer Keith WC accuracy at 980 fps and 315 ft-lbs 3.9 grain powder.jpg
    Elmer Keith WC accuracy at 980 fps and 315 ft-lbs 3.9 grain powder.jpg
    93.8 KB · Views: 90
Last edited:
One more Chronograph data

Here again I shot 2 shots of my reloads with 3.8 grain O***a scavenged shotshell powder.
The first shot again the Caldwell Chronograph App did not Register but the Chrono itself yes and it showed 981 fps which translates to 316 ft/lbs of energy.
That is plenty of energy since that is an accuracy load.

The second shot however was recorded by the Caldwell App and here is the result (Format is this time better):

Created: 20-02-2017 06:29:31 PM
Description: 148 Lee lead cast Wadcutter
Notes 1: Elmer Keith style bullet. 3.8 grain O***a powder (scavenged)
Notes 2: 357 mag SAA Pietta 1873 5.5“ revolver
Distance to Chrono (FT): 4.00
Ballistic Coefficient: 0.075
Bullet Weight (gr): 148.000
Altitude (FT): 400.0
Temp: N/A
BP: N/A
Shots
# FPS FT-LBS PF
1 991 322.79 146.67
Average: 0.00
StdDev: 0.00
Min: 991
Max: 991
Spread: 0
True MV: 0.00
Shots/sec: 0.00
Group Size (IN): 0.00
Click to expand...

There is therefore an 10 fps difference between both shot but I think that sample is ample representative.
With 3.8 grain of powder I do not get sticky cases but flat primers and ample energy Levels in the ballpark of an 9mm Luger.

Considerd with These 2 shots I did not hit my target (first bullet struck the target at the edge and both were high) but maybe I was flinching worried the chrono would not record again.

OBSERVATION: These Elmer Keith style bullets get me roughly the same velocity using 3.8 grain of O***a powder than the Tumble Lube design with 3.6 grain of O***a powder.
The TUMBLE LUBE design bullet definetelly must have an edge on Efficiency equivalent of an 0.2 grain of powder weight. You can save about 0.2 grain of powder, ceteris paribus, with the Tumble Lube design.
 
Last edited:
I just weighted the water Content of my 9mm Luger cases loaded with 124 grain Lee lead cast Tumble Lube bullets.
As per instructions of Unclenick.

Those 9mm Luger give an water weight of 6.3 grains.

That is less than 7.5 grains but These lead bullets just do not chamber when not seated deeper.
 
Adjusted powder charge to OAL calculations

Vitha Vhiouri states 4.4 grain minimum powder for VV N330 using an 124 grain LSWC (I assume this is some sort of Trucated Cone. Which I am using) in the 9 mm Luger for an OAL of 1.142".

My OAL is 1.030".

So I saw on another forum an calculation to adjust minimum powder weight for reduced OAL.
Like this:
4.4 grain VV N330 divided 1.142" OAL multiplied my own reduced OAL of 1.030" = New minimum powder charge for the reduced OAL (deep seated bullet).

4.4 / 1.142 * 1.030 = 3.96 grains of N330.

Is this calculation correct?

The Lee 0.5 powder measure dipper gives me (scraped of) 3.8 grain to 3.9 grain of powder by volumen. The Water weight of the powder space in the case is 6.3 grains.
 
You must log in or register to reply here.
Back
Top