Pulling apart old loads...

[drop_point]

I had loaded around 20 rounds of ammunition three or four years ago before my move. I had loaded the magazine for my rifle as well as one of those nylon cartridge sleeves for a rifle's buttstock, though I keep the sleeve in my pocket while hunting. I had a total of six rounds remaining, which I don't consider enough rounds to take several hours' drive away for a hunting trip.

This year I decided to load a different bullet considering the previous bullet has been rare as hen's teeth and hunting bullets aren't something I typically stock up on. The new bullet just isn't working out through three powders, seating depth test, etc. I was concerned something was wrong with the rifle. I swapped scopes, checked all the fasteners, and even scrubbed the bore with no avail.

I decided to shoot three of the remaining six rounds to see if the new bullet really was performing that poorly. Three rounds under 1/2 MOA. That left me three rounds. Turns out a friend told me he had a partial box of the very bullets I had been shooting another friend had given him. One bad thing: I had lost my data book in the move and I can't find the MTM ammo box I had affixed a copy of the load data to.

I decided to pull apart the remaining three rounds after taking length measurements to get powder charges. I noticed the powder came out in clumps. The three charges were inconsistent @ 43.2 gr, 43.4 gr, and 43.5 gr. I had remembered from memory the load was supposed to 43.3 gr. These rounds were loaded with a Chargemaster. Rounds were meticulously loaded to 0.1gr according to the Chargemaster and special care to make sure no powder was lost in the process. All reloading components kept in a climate controlled basement with a dehumidifier. Rounds were carried while hunting for three seasons.

What could cause this variance in charge weight when the rounds were deconstructed? Is it being exposed to the elements and thus COLD temperatures and varying humidity? Could humidity cause the powder to weigh differently? Is this common? Or was something funny going on with the Chargemaster?

Any insight would be appreciated! Thank you in advance.

 

[Mark W]

If the powder was clumping, are you positive that no powder stuck inside any of the cases?

 

[lawman29]

The stated accuracy of the charge master is +/- 0.1 so only one round 43.5 is outside the given range. Additionally what scale did you measure the 3 pulled charges and what was it's +/- accuracy range? If it was also +/- 0.1 the 43.5 could be 43.4 putting it in the original accuracy range....

 

[DiffEQ]

The three charges were inconsistent @ 43.2 gr, 43.4 gr, and 43.5 gr. I had remembered from memory the load was supposed to 43.3 gr. These rounds were loaded with a Chargemaster.

My initial reaction before reading this was, "probably a Chargemaster or Hornady."
I suspect you know that clumping is no big deal. If you got all the kernels out, easy possible it's the auto dispenser scale w/ drift.

 

[drop_point]

If the powder was clumping, are you positive that no powder stuck inside any of the cases?

Absolutely checked, nothing left in the case.

 

[drop_point]

The stated accuracy of the charge master is +/- 0.1 so only one round 43.5 is outside the given range. Additionally what scale did you measure the 3 pulled charges and what was it's +/- accuracy range? If it was also +/- 0.1 the 43.5 could be 43.4 putting it in the original accuracy range....

That's quite possible, however I was under the impression that it was +/- 0.05 gr?

 

[drop_point]

My initial reaction before reading this was, "probably a Chargemaster or Hornady."
I suspect you know that clumping is no big deal. If you got all the kernels out, easy possible it's the auto dispenser scale w/ drift.

I know clumping isn't a big deal. I've never experienced such large drift and typically re-calibrate 20-30 rounds. I've typically had pretty good luck with it.

 

[snert]

In the arcane pursuit of knowledge (why did it clump) and why was it a smidge (scientific term) different in weight when it came out, I have no answer. A couple WAGS: Your scale reads a bit different due to age? The Powder has ground shrinkage?

I am only joking.

I can't answer your question, but can make an observation: You seem happy with how they shot...and THAT is the true test, isn't it?

Be glad you have enough bullets to load for a hunt. And unless you are shooting some darn small critter, .01-.02 grain is totally meaningless.

 

[jepp2]

That's quite possible, however I was under the impression that it was +/- 0.05 gr?

I use my Chargemaster as my auto dump for my Fx120i. So I see what CM says they weigh, then I see what the A&D says they weigh, for every single charge I load. The results could easily be the numbers you found on re-weighing the charges.

 

[drop_point]

I use my Chargemaster as my auto dump for my Fx120i. So I see what CM says they weigh, then I see what the A&D says they weigh, for every single charge I load. The results could easily be the numbers you found on re-weighing the charges.

That's pretty crazy. I've probably got some false confidence in it after seeing some of the tests comparing the two from Erik Cortina and a few others.

 

[D-4297]

One tenth of a grain would be near meaningless at the distance of most hunting shots taken . Not really a major issue for a hunting round . I did run into a scale pan issue , after cleaning my nice aluminum scale pan to shiny , after I had zeroed the scale . Opps ! I loaded up 25 rounds for a F-TR string that were , in actuality , two and a half tenths light . And I spent quite a long time that day , trying to figure out why my "second" string at 600 was all low X's , and low tens . Yes Virginia ; it does matter at distance .

 

[searcher]

The powder clumping might have been a result of having loaded the brass before the interior of the brass casings were COMPLETELY dry, in the even you may have sonic cleaned or otherwise used liquids on the brass before loading - such as dipping in water after annealing, etc.. I once loaded a batch of 7 MM Rem Mag ammo a few days after I sonic cleaned the brass - which I thought was completely dry when I charged. Ammo performed poorly. I pulled bullets to find the clumped powder. I have hunted with a lot of ammo in inclement weather but never had powder absorb enough moisture to cause problems - other than the "weld" between bullet and brass which will occur over time.

 

[drop_point]

One tenth of a grain would be near meaningless at the distance of most hunting shots taken . Not really a major issue for a hunting round . I did run into a scale pan issue , after cleaning my nice aluminum scale pan to shiny , after I had zeroed the scale . Opps ! I loaded up 25 rounds for a F-TR string that were , in actuality , two and a half tenths light . And I spent quite a long time that day , trying to figure out why my "second" string at 600 was all low X's , and low tens . Yes Virginia ; it does matter at distance .

Not really concerned with it causing problems per se. I wanted to load them to what they were which grouped quite well, but I wanted to learn from the experience.

 

[drop_point]

The powder clumping might have been a result of having loaded the brass before the interior of the brass casings were COMPLETELY dry, in the even you may have sonic cleaned or otherwise used liquids on the brass before loading - such as dipping in water after annealing, etc.. I once loaded a batch of 7 MM Rem Mag ammo a few days after I sonic cleaned the brass - which I thought was completely dry when I charged. Ammo performed poorly. I pulled bullets to find the clumped powder. I have hunted with a lot of ammo in inclement weather but never had powder absorb enough moisture to cause problems - other than the "weld" between bullet and brass which will occur over time.

Shouldn't have been any problems with moisture. I don't use water when annealing or any kind of sonic cleaner. I do have a wet tumbler but didn't own it when I loaded those. Hunting rounds I typically don't even tumble.

They did, however, have the "weld" which you speak.

It wasn't so much that a problem was caused, but rather why the weight change? I have read that loading at different humidity can change the weight of the powder in gr. The .3gr weight variation on the three rounds I broke down made curious if that was even possible with loaded rounds? I don't know.

 

[Webster]

I had loaded around 20 rounds of ammunition three or four years ago before my move. I had loaded the magazine for my rifle as well as one of those nylon cartridge sleeves for a rifle's buttstock, though I keep the sleeve in my pocket while hunting. I had a total of six rounds remaining, which I don't consider enough rounds to take several hours' drive away for a hunting trip.

This year I decided to load a different bullet considering the previous bullet has been rare as hen's teeth and hunting bullets aren't something I typically stock up on. The new bullet just isn't working out through three powders, seating depth test, etc. I was concerned something was wrong with the rifle. I swapped scopes, checked all the fasteners, and even scrubbed the bore with no avail.

I decided to shoot three of the remaining six rounds to see if the new bullet really was performing that poorly. Three rounds under 1/2 MOA. That left me three rounds. Turns out a friend told me he had a partial box of the very bullets I had been shooting another friend had given him. One bad thing: I had lost my data book in the move and I can't find the MTM ammo box I had affixed a copy of the load data to.

I decided to pull apart the remaining three rounds after taking length measurements to get powder charges. I noticed the powder came out in clumps. The three charges were inconsistent @ 43.2 gr, 43.4 gr, and 43.5 gr. I had remembered from memory the load was supposed to 43.3 gr. These rounds were loaded with a Chargemaster. Rounds were meticulously loaded to 0.1gr according to the Chargemaster and special care to make sure no powder was lost in the process. All reloading components kept in a climate controlled basement with a dehumidifier. Rounds were carried while hunting for three seasons.

What could cause this variance in charge weight when the rounds were deconstructed? Is it being exposed to the elements and thus COLD temperatures and varying humidity? Could humidity cause the powder to weigh differently? Is this common? Or was something funny going on with the Chargemaster?

Any insight would be appreciated! Thank you in advance.

Powder in clumps. I would think moisture had to be present? Did you wet tumble polish the cases?

 

[PigButtons]

I've read your O Post several times and the thread through this morning, so let me venture an opinion. 43.3 was your "remembered" initial weight, so with the CM the 43.2 and the 43.4 are both within the margin of error for the device. The 43.5 could be because of humidity at the time of original loading, and the clumping due to initial moisture content of the powder as manufactured being condensed out of suspension during the repeated exposure to cold during winter hunting.

Or even differences in barometeric pressure, the calibration of the scale over three years, the corieolis effect, Sun spots, phase of the Moon, global warming... / Sarc off /

 

[searcher]

If my load went south due to a .3 grain powder differential - a big priority would be to work up a new load with a wider accuracy window. I really like it when I can find a hunting load that shoots great within a 1 1/2 grain range. That will keep me in the groove in both hot and cold weather - and with a bit of powder weight deviance - though I still hand weigh my charges.

 

[drop_point]

Powder in clumps. I would think moisture had to be present? Did you wet tumble polish the cases?

There was no moisture in the cases at time of loading.