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Old February 5, 2017, 08:46 AM   #1
TheGuyOfSouthamerica
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Chronograph Data: Elmer Keith style vs Lee Tumble Lube 148 grain Wadcutter velocity.

Hi,

I just chronoed the Lee Tumble Lube 148 grain Wadcutter .358" and I got 1010 fps. It is Lees propietary lube groove design with many small grooves.

Here the Chronograph data (I managed to get working the APP but the Format is somewhat meager):
Quote:
Created: 05-02-2017 09:48:18 AM Description: 148 grain lee tumble lube Wadcutter Notes 1: Notes 2: Distance to Chrono (FT): 3.00 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 1010 335.29 149.48 Average: 0.00 StdDev: 0.00 Min: 1010 Max: 1010 Spread: 0 True MV: 0.00 Shots/sec: 0.00 Group Size (IN): 0.00
As you can see this TL design did have an velocity of 1010 fps and the 148 grain TL Wadcutter was loaded with 4.0 grains of powder. The energy it had was 335 fps.
This bullet loaded very easy and is very Slick.
The case is on the edge to get a bit more sticky but is LESS then with the Elmer Keith style bullets maybe due to reduced friction of the bullet and therefore a bit reduced pressure. The primer flattened but is Ok.
Like Picture below this bullet was loaded the same way.

For comparison...

The same bullet from Lee but with Elmer Keith style (traditional style) gave me 1001 fps of velocity as you can see in the following Picture (then the APP didn't work somehow) and 329 ft/lbs of energy:



Both rounds are loaded like this:



This round is seated with more difficulty and more force has to be applied to seat it.

Basically there is not that much of an difference in velocity. Both rounds have been loaded to exactly 4.0 grains of the same powder.
So maybe the design make the difference of 9 fps or any other variable can be the cause as well.

ADDENDUM
Here I post again other Chronograph data again for comparison

Other data according to the Chronograph
First Group is the Lee 148 grain lead Wadcutter (Elmer Keith syle lube grooves) and second Group is the bullet you see in the first Picture the Lee 124 Truncated Cone 9mm Luger lead bullet (Lee tumble lube design). All shot from the SAA 357 Magnum Revolver and loaded like in Pictures of this post.

148 grain Wadcutter Lee lead .358" bullet loaded with Saga 3.2 grain scavenged powder gives 860 fps of velocity. 243 ft/lbs

148 grain Wadcutter Lee lead .358" bullet loaded with J&G 3.1 grain scavenged powder gives 863 fps of velocity. 245 ft/lbs

148 grain Wadcutter Lee lead .358" bullet loaded with Orbea 3.0 grain scavenged powder gives 836 fps of velocity. 230 ft/lbs
148 grain Wadcutter Lee lead .358" bullet loaded with Saga 4.0 grain scavenged powder gives 1001 fps of velocity. 329 ft/lbs
124 grain TC Lee lead .356" bullet loaded with J&G 3.1 grain scavenged powder gives 892 fps of velocity. 219 ft/lbs

124 grain TC Lee lead .356" bullet loaded with Orbea 3.0 grain scavenged powder gives 871 fps of velocity. 209 ft/lbs

124 grain TC Lee lead .356" bullet loaded with Saga 3.1 grain scavenged powder gives 848 fps of velocity. 198 ft/lbs

Last edited by TheGuyOfSouthamerica; February 5, 2017 at 09:08 AM.
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Old February 5, 2017, 12:19 PM   #2
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I have NEVER seen a wadcutter seated THAT DEEP.

No wonder you got pressure signs.

There is absolutely nothing to glean from such a minor difference in velocity.

What is the point of this exercise?
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Old February 5, 2017, 12:22 PM   #3
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Not an answer to your report, but looking at your pics of the (very) deep seated bullets I would be concerned. Not with the pressures as I've read your previous posts on the subject, but about the bullets themselves. Straight sided cases are tapered on the interior several thousandths, depending on how deep the measurement of the walls takes place. I would think seating this deep would have a tendency to swage the bullets down in OD. Have you pulled and measured any of your deep seated bullets? Same size as pre-seating?
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Old February 5, 2017, 12:32 PM   #4
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Check this link

http://www.range365.com/federal-38-s...oming-to-range

Federal makes such an bullet as well (similar) with the same principle.
We'll see how Long they last on the market.

Federal .38 Special +P HST Micro. Those are deep seated (regular???) hollow Point bullets.

I can not see any leading in the Barrel of the Revolver. The deep seating is about the same dimensions as for the 9mm Luger round. I mean regards empty Volumen of the case. Like this the 38 spl case has the same empty airspace as does the normal loaded 9mm Luger have (loaded with an lead bullet which go in deeper in the 9mm Luger case as well as regular FMJ's).

The Point of this test is as the thread description says: see if the tumble lube lube groove Lee design causes to the bullet a higher velocity than the regular lube grooves.
Lee states on their Webpage their propietary design gives more velocity due to reduced friction (I guess).

Last edited by TheGuyOfSouthamerica; February 5, 2017 at 12:38 PM.
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Old February 5, 2017, 12:40 PM   #5
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Well, the Federal page says the bullet is seated flush with the case mouth like a commercial wadcutter. You are achieving your goal of minimizing powder use by increasing the total expansion ratio, but the penalty may be higher pressure than cast bullets are usually fired at without a gas check.

I'll put my same QuickLOAD prediction graph here so anyone who hasn't seen your other thread on the topic can look at it.

The Tumble Lube bullet is slightly shorter than the standard wadcutter, but otherwise you don't expect much difference. It shoots more accurately for me, but I am using it at normal .38 Special target load pressures.

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Old February 5, 2017, 12:50 PM   #6
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Unclenick,

The seating depth of These Wadcutters are

0.131" from flush measured with an caliper.

Thank you for your technical answer.

I would be rather glad if you could explain the subject (your graph) rather extensively since I did not understand it completely. You say I rise Expansion rate of the powder and that allowed me to reduce the powder quantity?
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Old February 5, 2017, 05:44 PM   #7
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Dear Unclenick,

I use an 38 spl case for These reloads.
Could you run that in the Software as well together with the seating depth of 0.131" below flush?

If you use 357 mag case instead of an 38 spl case you may get different pressure Levels.

Data to calculate pressure with Quickload.

bullet length: .557"
case length: 1.139"
seating depth (from flush): .131"

Seating depth= case length+bullet length-OAL+[.131]
SD= 1.139+.557-1.139+.131
SD=0.688
Seating depth for my Wadcutters therefore should be 0.688" (if I got the formula correct. Please check).

I noticed one Thing: the tumble lube bullet is on it's Ends about .362" in Diameter and on the lube grooves it has a Diameter of about .355".
That explains the ease for seating and slickness. It basically rides in the Barrel only on it's Ends.

Last edited by TheGuyOfSouthamerica; February 5, 2017 at 06:06 PM.
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Old February 5, 2017, 06:21 PM   #8
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Unclenick,

However. Since you used in Quickload an 357 mag case I believe you have to add the difference of case length between 357 mag and 38 spl (what I use) to the Seating depth to be able to use the Calculations in the graph based on the Quickload.

1.275" is the length of an 357 mag
1.139" is the length of an 38 spl

so 1.275-1.139= 0.136"

This has to be added to the 0.688" of Seating Depth of my 38 spl case in order to read the pressure directly from your 357 mag graph.

0.688+0.136= 0.824 would be the actual seating depth in an 357 mag case.
I should get then an muzzle velocity of 1117 fps which does not match the reality.

Are my resonings correct? I fear not since the end result is not matching. What matches though is about the Seating Depth of 0.688", Muzzle Velocity of 974 fps+ and Energy of 312 ft/lbs+
Even with that something is still wrong since SD and velocity do not match very well.

Having an Seating Depth of 0.688" I should get an velocity of about 1050 fps (almost match) and an energy of over 400 ft/lbs (no mtch at all) and a pressure of about 31000 psi (according to the flat primer I must get more).
Maybe the cylinder gap makes the difference!

Last edited by TheGuyOfSouthamerica; February 5, 2017 at 06:31 PM.
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Old February 5, 2017, 06:39 PM   #9
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The Seating Depth is actually 0.688".

I just measured it with the caliper. It's measured from the mouth of the case how deep the bullet enters with the base in the case. So 0.688" is measured from the case mouth and there you find the base of the bullet.

from this data whoever has Quickload can extrapolate the pressures I get. Just Need to Change the above graph with an 38 spl case to get accurate readings.
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Old February 5, 2017, 08:08 PM   #10
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I have read your posts on deep seating, that was not my question. Since the case tapers down in the ID, the inside diameter gets smaller, is there any bullet swaging? That was my question...
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Old February 5, 2017, 08:27 PM   #11
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Dear mikld,

There is no way I can verify that.
The only hint I have is what I learned in Forums about the 38 spl and 357 mg case.
The 38 spl case is supposed to have an thicker wall towards the base about 1/3 of it's case length.
The 357 mag case is supposed to have an thicker wall towards the base about 1/2 of it's case length.

However here are some studies:



Source of Picture and additional info (All rigths of the picture belongs to the author in the link): http://www.taurusarmed.net/forums/re...ial-brass.html


According to that and if that is true the lead bullet in the 38 spl case I use is NOT Meeting yet (or is right at) the thicker (tapered) wall.

As concerns me I do not worry about that since leading is not an issue.
Attached Images
File Type: jpg Wall thickness and taper 38 spl case.jpg (66.0 KB, 457 views)

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Old February 6, 2017, 11:08 AM   #12
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This is the effect and Deformation one of These 148 grain Lee Tumble Lube Wadcutters make if shot a 200 Kg/450 lbs Beef heifer with it (where the blue arrows shot to in the Picture).
This round was loaded so it should have 1010 fps and 335 ft/lbs of energy.



The high Zinc Content makes it break in two and since it is soft lead it deforms readily if it Encounters an hard object like in this case a rib.

We slaughtered an 200 Kg Beef animal and The bullet shown is the first shot which is a miss (of the head) and it went into it's shoulder legthwise and the ribs made it deforming.
After this shot the animal walked half a mile were we wanted it to slaughter. Sometimes the animal was resting a bit but it seemed not even Feeling the first hit into the shoulder and it was not upset at all.
The second shot was with another 148 grain WC but Elmer Keith style (loaded weakly to about 245 ft/lbs) which went into the head and dropped the animal immediatelly (shotplacement between the horns a tad lower).

This Shows again an 380 Auto is very much capable and shot Placement is the most critical Thing. Penetration is crucial as well and not so much Expansion. Expansion I would even skip completely for Home Defense rounds.
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File Type: jpg WP_20170206_12_01_23_Pro.jpg (67.7 KB, 665 views)
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Old February 6, 2017, 02:50 PM   #13
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That chart shows an exponential increase in pressure going from .6 seating depth to .8. Not only are you pushing the envelope on the pressures you're also deforming the bullet and probably throwing accuracy out the window.

I realize getting powder is difficult down where you are located, but you are risking permenate damage to your gun and yourself by trying to maximize pressure while saving pennies on your powder cost.
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Old February 6, 2017, 05:18 PM   #14
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Quote:
Originally Posted by The GuyOfSouthAmerica
Are my resonings correct?
QuickLOAD only uses case length to determine water capacity. It doesn't have an argument for freebore. Pressure might be a little lower due to the bullet having to jump the extra 0.135" from the mouth of the .38 Special case to the throat of the chamber. There may be a bit of additional gas leakage there. However, due to gas cutting, most .357 chambers that .38 Special cases are used in will gradually build up lead in that extra space, so any difference from using a .357 case gradually goes away. This is the reason lead has to be cleaned carefully from a .357 chamber after using .38 Special cases and before using .357 cases again. The .357 case mouth can jam in the lead and either get a large pressure increase of refuse to chamber at all.

The increase in pressure with seating depth will be exponential no matter what case you use. It just may not track those exact values due to individual gun dimensions and the fact QuickLOAD lacks arguments both for freebore and for barrel/cylinder gaps.
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Old February 6, 2017, 06:17 PM   #15
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I chronographed today again one shot I loaded today and the Lee 148 grain Tumble Lube bullet had again exactly 1010 fps velocity. I loaded it with an powder dipper by Volumen to 4.0 grains powder.
That Shows the consistency of Volumen (dipper) loading and the chronograph works correctly.

The shot I shot at the heifer today was a miss but all other test shots with the TL design were right on target at 5 Yards.

The bullet retrieved from the animal has an partially intact base and no signs of deformed base but I can see still lube on the base (blue Color as you can see my lube stick in the previous Picture).

I just checked the cylinder of the Revolver and I can NOT see any lead deposits on the exiting Ends nor in the interior.
As well I tried to put in 357 mag factory rounds and they go in like new and fall again freely out. No resistance whatsoever.
I guess I can deduct from that there is no lead deposits at all. And dangerous pressure rise due to Barrel and chamber blockage may not be the case.

I observed again same or higher velocity with the Tumble Lube design and more I observed These have way less recoil than conventional Wadcutters. These TL lube designs shoot with the recoil of an 22 LR. I am impressed about the recoil reduction of the Lee Tumble Lube design.
As said before the TL bullets seat way easier than conventional bullets so I deduct from that there is way less friction from the bullet to the bore.

If my Seating Depth is 0.688" then I am according to the graph of Unclenick at pressures of about 30000 psi. I get however flat primers most of the time so I may guess I am roughly at 35000 psi of pressure.
The graph of Unclenick is based on 357 mag case which may give false conclusions for 38 spl cases.

Another Observation however may be done and that is I get less often an flat primer using the TL design. Not allways the primers are as flat but most of the time. That tells me the TL design may reduce the over all pressure.
The Report using the TL design however is very loud as bystanders tell me.
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Old February 6, 2017, 06:23 PM   #16
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Same Thing does Federal if they seat their bullets deep as well with their

Federal .38 Special +P HST Micro
http://www.range365.com/federal-38-s...oming-to-range

They save themselves some powder (at least 20% to 25% of powder is getting saved with this method) and let physics do the Job "for free". But they Charge probably the customer the "for free" part not lowering the Price.
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Old February 8, 2017, 11:55 AM   #17
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They are not seating as deeply as you are; only flush with the front of the case. This is because, as the ammunition is to be fired in light, snubnose .38 Special revolvers, they do not want to exceed .38 Special +P pressures as you do for your .357 revolver.

They are doing the deep seating not to save powder, but because snub nose revolvers a well-known for very inconsistent performance. One fellow on another forum had one for which the velocity of his load was varying 25%, from about 488 fps to about 650 fps. Seating deeper and cutting out air space helps reduce that. It also adds to the time the bullet takes to clear the muzzle, letting the powder to build pressure against it for a little longer.
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Old February 8, 2017, 02:18 PM   #18
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I admire your persistence in making do with what you have. But I do wonder how you can load a bullet to higher velocity and say it has less recoil. The physics don't seem to allow that.
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Old February 8, 2017, 06:53 PM   #19
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Thanks Unclenick and others,

Try to compare:
My Nagant style reloads: 4.0 grain VV N330; 148 grain Wadcutter; 1010 fps.
Normal (seated) reloads: 4.0 grain VV N330; 148 grain Wadcutter; ???? fps.

Would be nice if someone would load in an normal manner an 38 spl case like above (to be shot ONLY in an 357 mag 5.5" Revolver).
I bet if the reload is normally seated you will use 25% more powder to achieve the 1010 fps velocity OR will have lower velocity with the 4.0 grain VV N330 powder.

It is a mistery for me as well why the Tumble Lube design has less felt recoil than the Elmer Keith style bullet. But each time I shot those I noticed an very light recoil with the TL design vs the Keith style have an way more pronounced recoil and muzzle flip.
It is a fact the TL design seat very easy on the press which is not the case with the Keith bullet. It for sure has something to do with bullet friction to the bore (inicial acceleration may vary and be distribuited more evenly over the bore and time with the slicker TL design bullet).

The Lee Tumble Lube design bullets are definetelly the better design bullet and are technically IMHO more advanced as the Elmer Keith style. Besides that the TL design leads less (some lead smears on the end of the muzzle are gone since I use the Tumble Lube design.
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Old February 12, 2017, 05:56 PM   #20
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I just cleaned my SAA Revolver to see if the Lee 148 grain Tumble Lube Wadcutters are leading the bore. In post # 12 you can observe the "lipstick" lube (animal Crayon marker) which I use as lube.

I saw some deposits in the bore but as I cleaned it with an brass brush (Hope's #9 Kit) onto an White paper all what came out were lube deposits or sooth deposits. Touched with an finger they smear paint and lube. So what came out was not lead deposits but only lube which is good for the bore as it protects it from rust.

After the cleaning the bore Looks shiny brand new. This Pietta SAA 1873 357 mag Revolver actually has only seen lead bullets all it's Shooting except about 25 shots of factory jacketed ammo when I bougth it.

I am really glad to have found "casting" as an cheap alterntaive for bullets and it is so sucessfull. Factory bullets are locally not availlable.

If Prices of bullets go up in the US just start casting your own lead bullets. They are equal or better than factory FMJ bullets and more ecologically friendly since you can recast them if you find them again (this happens often to me).
In my experience lead cast bullets give you higher velocities, deform easy in an unpredictable shape (Kind of an hollow Point), are way cheaper and reduce pressure of the case (less risk of overpressure/oveloading).

Overall It may even be that lead bullets erode less Barrels as FMJ bullets an the gun lasts you longer.

Last edited by TheGuyOfSouthamerica; February 12, 2017 at 07:37 PM.
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Old February 14, 2017, 11:40 AM   #21
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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:
Quote:
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
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)!

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Old February 14, 2017, 03:46 PM   #22
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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 by TheGuyOfSouthamerica; February 14, 2017 at 04:21 PM.
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Old February 14, 2017, 07:02 PM   #23
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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).
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Old February 14, 2017, 08:14 PM   #24
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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.
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Old February 14, 2017, 08:51 PM   #25
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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.
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