Sport Pistol for .40 S&W Major PF

[e-mishka]

Shot few loads of SP through my Tanfo Limited

 

4.66gn, 180gn coated bullet,  OAL 1.139

AV 955

SD 4

PF 171.9

 

4.62gn, 180gn coated bullet,  OAL 1.139

AV 944

SD 6

PF 169.9

 

All mixed brass, Winchester SPPs

 

 

Shot pretty well, I'll load some more for practice. I use N320 currently
 

 

Edited February 18, 2019 by e-mishka

[ringram]

Just finished 16lb of Sport Pistol, before that N320 for a couple of years. Sport Pistol is a little dirtier, but you need to shoot loads to notice. I mean thousands. 

 

They seem very comparable to me. But Sport Pistol is half the price. Powder Valley said they are expecting to be restocked some time this month (FEB19) as they are all out now.

 

 

[FCL8]

Powder Valley just got their order in 3/1. They have 1 lb., 4 lb. and 8 lb. canisters at this moment.

 

[HesedTech]

On 2/18/2019 at 9:53 AM, e-mishka said:

 

4.66gn, 180gn coated bullet,  OAL 1.139

 

4.62gn, 180gn coated bullet,  OAL 1.139

 

 

 

 

Wow, I amazed you can measure that accurately.  .04 difference. My scales and the drop from Dillon probably has that much variance. 

 

 

[George16]

29 minutes ago, HesedTech said:

 

Wow, I amazed you can measure that accurately.  .04 difference. My scales and the drop from Dillon probably has that much variance. 

 

 

All you have to do is do ten drops and averaged it. That’s what I do.

[jmtyndall]

 
Wow, I amazed you can measure that accurately.  .04 difference. My scales and the drop from Dillon probably has that much variance. 
 
 

You're probably right. The method below:

All you have to do is do ten drops and averaged it. That’s what I do.

Averages out and removes all the variance while giving the illusion of precision.

4.50gr could actually be 4.6, 4.4, 4.3, 4.7, 4.5 etc. Very few of the affordable instruments for reloading can accurately measure to the hundredth of a grain. Most powder kernels probably weigh on the order of 2-3x that anyways

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[Joe4d]

I had always assumed those measurements were from one of our international members that took the time to convert from metric for us Muricans

 

[MemphisMechanic]

2 hours ago, Joe4d said:

I had always assumed those measurements were from one of our international members that took the time to convert from metric for us Muricans

 

 

Nope. A lot of us don’t bother to turn our scales on unless we drop 5 to 10 charges on it, and average.

 

I want to know if “3.6” is actually 3.64 rounded down, or if it’s 3.51 being rounded up. My scale doesn’t have the accuracy to tell me that consistently until I’ve got 4-5 charges on it.

 

I never weigh things during the loading session either. I set my charge weight when developing the load, write it on a strip of masking tape and slap it on the measure, then produce ammo until I need to change charge weight for some reason. As long as the powder level in the cases continues to pass visual inspection for volume and the chrono data is consistent at the range, I’m happy.

 

Edited March 4, 2019 by MemphisMechanic

[HesedTech]

On 3/2/2019 at 6:44 PM, George16 said:

All you have to do is do ten drops and averaged it. That’s what I do.

 

I do that, but rounding up or down to the tenth is as accurate as it really gets, at least for me.

[HesedTech]

7 hours ago, jmtyndall said:

4.50gr could actually be 4.6, 4.4, 4.3, 4.7, 4.5 etc. Very few of the affordable instruments for reloading can accurately measure to the hundredth of a grain. Most powder kernels probably weigh on the order of 2-3x that anyways


 

I have a couple of scales and my Dillon drops never vary as much as your  example.  

 

What Memphis said is how I set the charge. 

 

 

Edited March 4, 2019 by HesedTech

[jmtyndall]

I am not insinuating that they do. I'm suggesting that averaging 10 throws is adding precision to a measurement that was not precise to begin with. Some may remember back to high school chemistry when we dealt with significant figures? Reporting 4.61gr when the scale only reads to the tenth would get you marked down points.

 

To add to that, I've also never seen a powder measure as consistent as people are claiming when they report powder charges to the hundredth of a grain. If 6 kernels of powder weight 0.1 grain then each kernel weighs 0.017gr right? Reporting a measurement to the hundredth place seems to imply that the measure never varys even 1 kernel of powder which just isnt true.

 

So sure, someone can report a load of 4.61gr, but it's still +/- 0.1gr.

 

We could argue powder drop consistency and accuracy of measurements all day. In the end it doesnt really matter if 10 round averages make people feel warm and fuzzy (in fact I set my charges this way, but I note every increment along the way and drop the non-significant figures). All I'm saying is someone asked about people being able to measure to the hundredth of a grain. The answer is they can't with the equipment most of us have on the bench. They can make it up though, and if they like doing that I dont see any reason they shouldn't.

 

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[rowdyb]

I had jobs with the County of San Diego and the University of California where it was my job to check their various facilities x-ray producing machines. For the County I was responsible for dentists, vets and chiropractors. If the person/tech selected 90kvp for 0.20 seconds then that better be what is actually produced and for that amount of time. The testing equipment and its calibration and the qc of the process taught me a fair bit about accuracy in different measurements. I learned more of the same getting our survey meters aka Geiger counters calibrated when I was in Iraq doing radiation safety for a program. Or when I was doing nuclear medicine and checking the sensitivity and specificity of multiple instruments to be used on patients or in the preparation of their medications every day, charting the results over years.

 

I am highly highly skeptical of any of the consumer scales we use in reloading to be accurate to anything more than 0.10 of a grain. What we consider precise in reloading for a pistol is laughably inaccurate compared to measurements in a laboratory setting. And that's ok, thankfully!

 

I agree with @jmtyndall

[muncie21]

8 hours ago, rowdyb said:

I am highly highly skeptical of any of the consumer scales we use in reloading to be accurate to anything more than 0.10 of a grain. What we consider precise in reloading for a pistol is laughably inaccurate compared to measurements in a laboratory setting. And that's ok, thankfully!

 

I agree with @jmtyndall

Completely agree Rowdy. 

 

I have worked in the health sciences industry for close to 20 years and can tell folks that precision scales are very, very expensive.  You can't judge a scale by the number of decimal places it displays, if the numbers beyond 1st/2nd decimal place are not accurate and repeatable.  For our (reloaders) quality scales, most of the time these numbers are just 'noise' and therefore essentially meaningless.

Edited March 4, 2019 by muncie21

[e-mishka]

On 3/4/2019 at 12:55 AM, jmtyndall said:

 

 

You're probably right. The method below:



Averages out and removes all the variance while giving the illusion of precision.

4.50gr could actually be 4.6, 4.4, 4.3, 4.7, 4.5 etc. Very few of the affordable instruments for reloading can accurately measure to the hundredth of a grain. Most powder kernels probably weigh on the order of 2-3x that anyways

Sent from my SM-G892A using Tapatalk
 

 

 

Yes it was 10 powder drops combined and averaged

[e-mishka]

Can anyone confirm if its temp sensitive? 

I ran 150 rounds of it last night and it was pretty good. I concur that it shoots a little bit dirtier then N320 but for practice and local matches its no biggie.

 

[858]

On 3/4/2019 at 7:37 AM, rowdyb said:

I had jobs with the County of San Diego and the University of California where it was my job to check their various facilities x-ray producing machines. For the County I was responsible for dentists, vets and chiropractors. If the person/tech selected 90kvp for 0.20 seconds then that better be what is actually produced and for that amount of time. The testing equipment and its calibration and the qc of the process taught me a fair bit about accuracy in different measurements. I learned more of the same getting our survey meters aka Geiger counters calibrated when I was in Iraq doing radiation safety for a program. Or when I was doing nuclear medicine and checking the sensitivity and specificity of multiple instruments to be used on patients or in the preparation of their medications every day, charting the results over years.

 

I am highly highly skeptical of any of the consumer scales we use in reloading to be accurate to anything more than 0.10 of a grain. What we consider precise in reloading for a pistol is laughably inaccurate compared to measurements in a laboratory setting. And that's ok, thankfully!

 

I agree with @jmtyndall

 

I use a lab scale. It is accurate to +/-.01 grains. It wasn't cheap.

[rowdyb]

21 hours ago, 858 said:

 

I use a lab scale. It is accurate to +/-.01 grains. It wasn't cheap.

Correct. No $20-150 scale is going to cut it if you want to measure something truly accurate as considered by professionals in other industries. What we do in our garages and basements is the difference between a B-17 and a stealth B-2 compared to scales and accuracy in science, medicine and such.

Edited April 16, 2019 by rowdyb

[858]

12 hours ago, rowdyb said:

Correct. No $20-150 scale is going to cut it if you want to measure something truly accurate as considered by professionals in other industries. What we do in our garages and basements is the difference between a B-17 and a stealth B-2 compared to scales and accuracy in science, medicine and such.

 

Agreed. Regular reloading positioned scales frustrated me to no end. They are all +/-.1gr on their very best day. Most probably cost $5 to make. 

[muncie21]

Good thing our sport doesn't require powder drops to be accurate to the hundredth of a grain. 

[MemphisMechanic]

@muncie21 that was my first thought too.

 

Hell, a ten drop average on my $40 digital Lyman scale is already more accurate than any auto powder drop is ever going to be, so we’re good to go with that.

 

If I can get a 2” group out of my ammo at 20yds and it chronos with an SD below 10, I’ve exceeded the requirements for shooting USPSA, and I’ll lock the press down and not think about the reloading side of the game any more.

[858]

2 hours ago, muncie21 said:

Good thing our sport doesn't require powder drops to be accurate to the hundredth of a grain. 

 

None of the shooting sports do but you don't have to average powder throws with a good scale. Averaging 10 shot charge weights is unacceptable once you get out of pistol shooting. I haven't changed my powder set up in a while but I weigh a few charges right after I refill the hopper to make sure the charge weight has settled. The first one or three throws read a little different than the rest.

 

 

[rowdyb]

nope, in what we do you can get by totally with a chrono and empirical data from shooting. heck, i use the cheapest digital calipers I can find.

 

but....... if you tell me your load is 3.35 gr of whatever I'm totally going to take it with a grain (get it) of salt.

[Muddawg900]

On 4/17/2019 at 3:44 PM, 858 said:

 

None of the shooting sports do but you don't have to average powder throws with a good scale. Averaging 10 shot charge weights is unacceptable once you get out of pistol shooting. I haven't changed my powder set up in a while but I weigh a few charges right after I refill the hopper to make sure the charge weight has settled. The first one or three throws read a little different than the rest.

 

 

For what it's worth, any time I fill a hopper from nearly or completely empty, I always cycle the hopper/charge bar on my dillons 5 or 6 times (charge a case and dump it back in the hopper) before I even consider weighing charges when I'm making adjustments or doing load development. 

[Riley]

I’ve been trying different loads in the CZ TSO 40 and I’m finding 4.5gr SP and a 180gr Blue Bullet to be just right at a 1.130-1.135 COAL gives me a 172pf measured at 15’.  Gives about a 30 ES and 9-11 SD. 

 

I tried 4.4 but was lucky to get 166.x PF.  ES was up in the high 40#s and SD was high teens I think. 

 

 

[zzt]

I have several reloading scales.  The most accurate is the one from Perigrine.  It is calibratable to different weight and is accurate to 0.01gr.  It is a bit of a hassle to use if there are any air currents around.  Turn on with nothing on the platen.  Put measuring cup on the platen, close cover and hit Tare.  Gently raise the cover, pour in the powder and gently close cover.  It takes about 5 seconds to settle.  It is used by long range bench rest shooters.  It even comes with a sharp tweezers for picking individual grains of powder out to get an exact weight.