Previous Thread
Next Thread
Print Thread
Hop To
Page 3 of 3 1 2 3
Re: Question about power measure consistency [Re: Axtell] #14174816 10/03/19
Joined: Dec 2002
Posts: 13,418
AJ300MAG Offline
Campfire 'Bwana
Offline
Campfire 'Bwana
Joined: Dec 2002
Posts: 13,418
I run the same scale coupled with an auto trickler. Depends on what your time is worth, I can dump enough loads to cover a 60 round midrange match in less than an hour and hold the tolerance you speak of.

.1/2 grains of varget equals 25 kernels of powder. I'm curious on what chronograp and what parameters people are setting when they say a dropped load is as consistent as a weighted load. 25fps variance on a .308 at 600 yards drops you out of the "10" ring...

300 BP

Re: Question about power measure consistency [Re: Remington725] #14174936 10/03/19
Joined: May 2015
Posts: 506
Axtell Offline
Campfire Regular
Offline
Campfire Regular
Joined: May 2015
Posts: 506
I use a Labradar, FX120i scale, ability to use good measuring tools and Quickload to figure out a good load.

Need single digit ES to compete, this carries over to my hunting handloads.

A recent example is a new to me Steyr 7mm-08, 6x MQ SWFA, 150gn ELD-X, 1038 yards 6.25" 3 shot group. This is my back up big game rifle.

Re: Question about power measure consistency [Re: jorgeI] #14175138 10/03/19
Joined: Jul 2001
Posts: 47,528
Mule Deer Offline
Campfire Oracle
Offline
Campfire Oracle
Joined: Jul 2001
Posts: 47,528
jorge,

Have you experimented with the height of the powder baffle inside the measure's tube? That can make a noticeable difference in consistency.


John

"Gunwriters, as you know, aren't as informed as their readers are and if it wasn't for the readers, there would be no need for writers..."--Shrapnel, May 2015
Re: Question about power measure consistency [Re: Remington725] #14175289 10/03/19
Joined: Dec 2015
Posts: 2,398
pete53 Offline
Campfire Ranger
Offline
Campfire Ranger
Joined: Dec 2015
Posts: 2,398
M.D. >i do use the long neck type piece under my Redding Benchrest powder measure and my baffle is between 2-3 inch above the powder cup cylinder is that about right height ? my question still is can gun powder be weighed accurate ? or is volume loading more accurate ? at the 100-200 yard bench matches they all volume load some use a 1-10 grain adjustment some use a 1-18 grain adjustment powder measures,most shoot 2`s and 3`s at 100 yds sometimes better too with their 5 shot groups.

Re: Question about power measure consistency [Re: pete53] #14175490 10/03/19
Joined: Jul 2001
Posts: 47,528
Mule Deer Offline
Campfire Oracle
Offline
Campfire Oracle
Joined: Jul 2001
Posts: 47,528
Pete,

The best way to determine baffle height is to experiment--with the powder you want to use. The best height will vary not only with the measure but the powder.

In general, it works to use a smaller powder measure for smaller charges, and a larger one for larger charges. I have several for various purposes, including one of the Lyman 55's with the Homer Culver micrometer conversion that Ken Oehler very generously gave me a few years ago. For many years that was the preferred measure by short-range benchrest shooters, and it still works VERY well.

The other side of powder measuring is that charge weight doesn't always mean consistency, since powder weight for a certain volume can vary with humidity and storage. Each time you open a jug of powder it can either gain or lose weight, due to humidity. It can either gain or lose weight, sometimes meaningfully. Weighing the same amount of powder many NOT result in the same results, while volume may come much closer.

Which is why proper powder storage--and leaving a container open as little as possible--can make a difference in velocity and consistency. However, whether this matters or not to most handloaders is another question!


John

"Gunwriters, as you know, aren't as informed as their readers are and if it wasn't for the readers, there would be no need for writers..."--Shrapnel, May 2015
Alpha

Re: Question about power measure consistency [Re: Remington725] #14176678 10/04/19
Joined: Dec 2015
Posts: 2,398
pete53 Offline
Campfire Ranger
Offline
Campfire Ranger
Joined: Dec 2015
Posts: 2,398
thank you Mule Deer ,i do have small and large Redding powder measures, i also have a reloading room that has a wood floor with plastic underneath my marine plywood ,i have electric base board heat for controlled dry temperature. i did screw up with size of this room its only 8x16 -8 feet high ,if i did it over 12 x 24 -8 feet high but i would still have the wood floor with electric heat. and again thank you,Pete53

Re: Question about power measure consistency [Re: Remington725] #14176834 10/04/19
Joined: Oct 2004
Posts: 5,902
PaulBarnard Offline
Campfire Tracker
Offline
Campfire Tracker
Joined: Oct 2004
Posts: 5,902
If a .5 variance is insignificant, answer me this. Folks often post ladder test results here and see appreciable differences within a .5g range. What gives?

Re: Question about power measure consistency [Re: PaulBarnard] #14176856 10/04/19
Joined: Jun 2004
Posts: 32,727
mathman Offline
Campfire Oracle
Offline
Campfire Oracle
Joined: Jun 2004
Posts: 32,727
I'd be more impressed by ladder tests if more than one or two shots were on each step of the latter.


"In the real world, think of the 6.5 Creedmoor as the modernized/standardized/optimized version of the 6.5x55/.260." John Barsness 2019
Re: Question about power measure consistency [Re: PaulBarnard] #14176910 10/04/19
Joined: Oct 2016
Posts: 972
Trystan Offline
Campfire Regular
Offline
Campfire Regular
Joined: Oct 2016
Posts: 972
Originally Posted by PaulBarnard
If a .5 variance is insignificant, answer me this. Folks often post ladder test results here and see appreciable differences within a .5g range. What gives?


The appreciable differences your seeing are most often caused from other factors, wrong powder, wrong primer, runout, etc, etc........ This is a short answer to a complicated question but in a nutshell if your seeing appreciable differences with a small change in powder charge there is a problem somewhere and it isn't the powder charge IME

It is possible to see an appreciable difference if you went from the edge of a node to out of the node however once you have achieved a load that is in the middle of a node .5 grain of powder isn't enouph to put you out of the node. I'm basing my reply off of the assumption that were talking about .5 grain of powder effecting a proper load at reasonable distances.

With a good load Ive not seen much that can be noticed even at 500 yds which is further than most hunters ever shoot



Last edited by Trystan; 10/04/19.

Good bullets properly placed always work, but not everyone knows what good bullets are, or can reliably place them in the field
Re: Question about power measure consistency [Re: PaulBarnard] #14176914 10/04/19
Joined: Jan 2007
Posts: 16,268
battue Offline
Campfire Kahuna
Offline
Campfire Kahuna
Joined: Jan 2007
Posts: 16,268
Originally Posted by PaulBarnard
If a .5 variance is insignificant, answer me this. Folks often post ladder test results here and see appreciable differences within a .5g range. What gives?



A long time ago in a far away land, Kenny Jarrett told me not to think twice about +/- 0.5 in a .280AI.


laissez les bons temps rouler
Bravo

Re: Question about power measure consistency [Re: battue] #14176963 10/04/19
Joined: Oct 2016
Posts: 972
Trystan Offline
Campfire Regular
Offline
Campfire Regular
Joined: Oct 2016
Posts: 972
Originally Posted by battue
Originally Posted by PaulBarnard
If a .5 variance is insignificant, answer me this. Folks often post ladder test results here and see appreciable differences within a .5g range. What gives?



A long time ago in a far away land, Kenny Jarrett told me not to think twice about +/- 0.5 in a .280AI.


Battue, I have noted that cartridges that are loaded to "higher powder operating pressures" are effected less concerning velocity when powder is added or taken away. Your mileage may vary but IME both the 280 AI and the 270 that have a high Sammi pressure rating benifit from this from what I have seen.

It doesn't surprise me that Kenny specifically mentioned the 280 AI due to its 65,000 Sammi pressure especially if he was comparing notes to a standard 280 that is much lower

It is for this reason that I have come to appreciate loads where accuracy is achieved at pressure! I'm also quite sure its one reason why bench rest shooters often run what we might consider almost insane pressures

Last edited by Trystan; 10/04/19.

Good bullets properly placed always work, but not everyone knows what good bullets are, or can reliably place them in the field
Re: Question about power measure consistency [Re: Remington725] #14178090 10/04/19
Joined: Jun 2004
Posts: 9,664
denton Offline
Campfire Outfitter
Offline
Campfire Outfitter
Joined: Jun 2004
Posts: 9,664
Why charge consistency matters less than most people think it does....

The muzzle velocity of commercial ammunition that I have tested has a standard deviation around 35 FPS. Assume for a moment that you have some kind of powder measuring device that is slow and laborious, but gives absolutely perfect weights every time. With this wonderful device, the standard deviation of your handloads is a very acceptable 30 FPS.

Now, for the sake of illustration, suppose a travelling salesman drops in on you and offers you a much faster but sloppy means of measuring powder, and the performance tradeoff is that the standard deviation of your powder charges will jump from zero to .15 grains. What will this do to the standard deviation of your muzzle velocity?

If you're loading your trusty 308 Winchester with between 44 and 47 grains of Varget behind a 150 grain bullet, you're loading in a region where an additional 1 grain of powder yields an additional 50 FPS. So .15 grains of powder is 7.5 FPS.

Now we can combine the variation due to all other factors, SD=30, with the variation of the new powder charging device, SD=7.5 FPS. They do not add linearly. The formula is

Square root (30^2 + 7.5^2),

and that is square root (900 + 56.25), or 30.92 FPS.

The decrease in the precision of the fast but sloppy charging system changes the standard deviation of the muzzle velocity from 30 FPS to 30.92 FPS. That is not enough to worry about, and most powder measures are better than SD=.15 grains.

This is a pretty good representation of what happens with mid to large size cases.


Last edited by denton; 10/04/19.

I don't associate with snobby people. I'm much too good for that.
Re: Question about power measure consistency [Re: Mule Deer] #14189371 10/09/19
Joined: Jun 2009
Posts: 1,625
Azar Offline
Campfire Ranger
Offline
Campfire Ranger
Joined: Jun 2009
Posts: 1,625
Originally Posted by Mule Deer
jorge,

Have you experimented with the height of the powder baffle inside the measure's tube? That can make a noticeable difference in consistency.


John,

Have you ever experimented with "Double Baffling" in a powder measure? I.e. Using two powder baffles in tandem, with one on top of the other rotated 90* (with the upper baffle placed with its drop slots perpendicular to the those of the lower baffle). I've read that it will further increase the consistency of a powder measure over using a single baffle. This tip was shared by a knowledgeable handloader who's opinion I trust, but I've never bothered to add a second baffle. I was curious if you had and what you may have found?

Thanks.


“There are three things all wise men fear: the sea in storm, a night with no moon, and the anger of a gentle man.”
― Patrick Rothfuss, The Wise Man's Fear
Re: Question about power measure consistency [Re: Azar] #14189394 10/09/19
Joined: Jun 2003
Posts: 36,432
jorgeI Online Content
Campfire Oracle
Online Content
Campfire Oracle
Joined: Jun 2003
Posts: 36,432
Originally Posted by Mule Deer
jorge,

Have you experimented with the height of the powder baffle inside the measure's tube? That can make a noticeable difference in consistency.


No i have not. I just have the standard baffle that came with the kit, but I'm open to learn!


Teddy Roosevelt, John Wayne, Winston Churchill paid to hunt....
Re: Question about power measure consistency [Re: Remington725] #14189421 10/09/19
Joined: Jan 2001
Posts: 24,259
Jim in Idaho Offline
Campfire Kahuna
Offline
Campfire Kahuna
Joined: Jan 2001
Posts: 24,259
Never going to knock the search for consistency since that's the name of the game in accuracy, but in the real world of sporting rifles how much effort vs. reward are we talking here?





Fwiw, the 6 powder baffles in my measure are moly coated and drop individual kernels through a laser reader which counts each one*. My razor also has 12 blades for a really close shave...

[Linked Image from i.imgur.com]











* Mathman, before you ask, the answer is yes. Kernels are also checked for size consistency and moisture content and those outside of user specified parameters are routed to a dump chute for use in plinking and short range off hand practice loads.....


Gunnery, gunnery, gunnery.
Hit the target, all else is twaddle!
Re: Question about power measure consistency [Re: Jim in Idaho] #14189450 10/09/19
Joined: Jun 2004
Posts: 32,727
mathman Offline
Campfire Oracle
Offline
Campfire Oracle
Joined: Jun 2004
Posts: 32,727
I'm not one of the powder charge OCD types around here. I run 3031 and 4064 through a measure. grin


"In the real world, think of the 6.5 Creedmoor as the modernized/standardized/optimized version of the 6.5x55/.260." John Barsness 2019
Re: Question about power measure consistency [Re: denton] #14201538 10/14/19
Joined: Oct 2006
Posts: 1,209
jstevens Offline
Campfire Regular
Offline
Campfire Regular
Joined: Oct 2006
Posts: 1,209
Originally Posted by denton
Why charge consistency matters less than most people think it does....

The muzzle velocity of commercial ammunition that I have tested has a standard deviation around 35 FPS. Assume for a moment that you have some kind of powder measuring device that is slow and laborious, but gives absolutely perfect weights every time. With this wonderful device, the standard deviation of your handloads is a very acceptable 30 FPS.

Now, for the sake of illustration, suppose a travelling salesman drops in on you and offers you a much faster but sloppy means of measuring powder, and the performance tradeoff is that the standard deviation of your powder charges will jump from zero to .15 grains. What will this do to the standard deviation of your muzzle velocity?

If you're loading your trusty 308 Winchester with between 44 and 47 grains of Varget behind a 150 grain bullet, you're loading in a region where an additional 1 grain of powder yields an additional 50 FPS. So .15 grains of powder is 7.5 FPS.

Now we can combine the variation due to all other factors, SD=30, with the variation of the new powder charging device, SD=7.5 FPS. They do not add linearly. The formula is

Square root (30^2 + 7.5^2),

and that is square root (900 + 56.25), or 30.92 FPS.

The decrease in the precision of the fast but sloppy charging system changes the standard deviation of the muzzle velocity from 30 FPS to 30.92 FPS. That is not enough to worry about, and most powder measures are better than SD=.15 grains.

This is a pretty good representation of what happens with mid to large size cases.




Thanks, Denton, math will show you that weighing every charge is a waste of time.

Re: Question about power measure consistency [Re: Mule Deer] #14201546 10/14/19
Joined: Oct 2006
Posts: 1,209
jstevens Offline
Campfire Regular
Offline
Campfire Regular
Joined: Oct 2006
Posts: 1,209
Originally Posted by Mule Deer
Pete,

The best way to determine baffle height is to experiment--with the powder you want to use. The best height will vary not only with the measure but the powder.

In general, it works to use a smaller powder measure for smaller charges, and a larger one for larger charges. I have several for various purposes, including one of the Lyman 55's with the Homer Culver micrometer conversion that Ken Oehler very generously gave me a few years ago. For many years that was the preferred measure by short-range benchrest shooters, and it still works VERY well.

The other side of powder measuring is that charge weight doesn't always mean consistency, since powder weight for a certain volume can vary with humidity and storage. Each time you open a jug of powder it can either gain or lose weight, due to humidity. It can either gain or lose weight, sometimes meaningfully. Weighing the same amount of powder many NOT result in the same results, while volume may come much closer.

Which is why proper powder storage--and leaving a container open as little as possible--can make a difference in velocity and consistency. However, whether this matters or not to most handloaders is another question!



I record the setting on my measure and once I've worked a load up, load by volume only. I have tried it enough times to convince myself that if I change powder lots, the velocity is more repeatable by volume than by weight.

Re: Question about power measure consistency [Re: Remington725] #14202329 10/14/19
Joined: Apr 2011
Posts: 33,014
hanco Online Content
Campfire Oracle
Online Content
Campfire Oracle
Joined: Apr 2011
Posts: 33,014
I throw a little low, then trickle up to the correct weight. I have a couple Redding powder measures. Varget throws really well, so does CFE 223. I load middle of the road pistol loads, so I throw them right in the case, weigh every tenth one.

Page 3 of 3 1 2 3

Moderated by  RickBin, SYSOP 

RR1
Who's Online Now
406 registered members (10gaugemag, 257heaven, 224th, 117LBS, 175rltw, 36 invisible), 1,092 guests, and 483 spiders.
Key: Admin, Global Mod, Mod
RR2/3










Fish & Game Departments | Solunar Tables | Mission Statement | Privacy Policy | Contact Us | DMCA
Hunting | Fishing | Camping | Backpacking | Reloading | Campfire Forums | Gear Shop
Copyright © 2000-2020 24hourcampfire.com, Inc. All Rights Reserved.
 
Powered by UBB.threads™ PHP Forum Software 7.7.3
(Release build 20190728)
PHP: 5.6.40 Page Time: 0.071s Queries: 14 (0.006s) Memory: 1.1743 MB (Peak: 1.4775 MB) Data Comp: Zlib Server Time: 2019-11-13 13:03:04 UTC
Valid HTML 5 and Valid CSS