Inconsistent Powder Weight in Factory Rounds

[jamross65]

I'm curious following on from the other thread on 'most accurate...' And don't want to hijack it.

cadex mentions pulling apart factory rounds and finding a significant variance in powder weight? Anyone else done this and by how much +/- do the powder weights actually vary? What's likely to suffer more, small case capacity or large?

I'm very pernickety when reloading with regards to powder weight but my mate is not so. I don't mean he is careless, just does not seem to be as fussy for getting that needle on the scales to be absolutely steady on the line but in reality his powder charge is probably plus or minus 4 or 5 grains of powder (not grains of weight!) and his opinion is that no matter what he will still be more accurate in measuring the weight than any factory round, which I suppose is true.

If factory ammunition is still grouping around an inch with such a large relative variance I am now guessing that I'm probably being too fussy and may never see that difference in accuracy consistency caused by a few grains of powder here and there????

Any thoughts?

 

[jamross65]

meant to add that the only factory ammo I use just now is 100grn SP Norma in the 243, as its hardly used compared to the other rifles and with that factory ammo it groups so well there is not really anything to be gained in home loading I feel...

 

[caorach]

I have some Federal Power Shok ammo in 308W and they are all different lengths, and I mean different enough to tell by eye that they are varying. I've never taken one apart because they shoot as accurately in my rifle as anything I can reload so don't want to waste them but I'm willing to bet the power weights vary as well. They weren't expensive either.

Most of the things you "must" do to reload accurate ammo are based more on OCD than on any statistically proven improvement in accuracy.

 

[sikadog]

I pulled 14 rounds of Federal 22-250 50grn there was a variation of .9 of a grain in some cases 34.2--35.1.
Ten of the cases varied by only .3 of a grain but the other 4 where .5,.8,.9,.9.

 

[Muir]

I'm curious following on from the other thread on 'most accurate...' And don't want to hijack it.

cadex mentions pulling apart factory rounds and finding a significant variance in powder weight? Anyone else done this and by how much +/- do the powder weights actually vary? What's likely to suffer more, small case capacity or large?

I'm very pernickety when reloading with regards to powder weight but my mate is not so. I don't mean he is careless, just does not seem to be as fussy for getting that needle on the scales to be absolutely steady on the line but in reality his powder charge is probably plus or minus 4 or 5 grains of powder (not grains of weight!) and his opinion is that no matter what he will still be more accurate in measuring the weight than any factory round, which I suppose is true.

If factory ammunition is still grouping around an inch with such a large relative variance I am now guessing that I'm probably being too fussy and may never see that difference in accuracy consistency caused by a few grains of powder here and there????

Any thoughts?

Factory ammo is loaded to volume. You can do the same and do just as well provided you are consistent. There are so many other important factors besides a few granules of powder.~Muir

 

[jamross65]

Factory ammo is loaded to volume. You can do the same and do just as well provided you are consistent. There are so many other important factors besides a few granules of powder.~Muir

Can you explain that further Muir regarding volume? I assume therefore that settling of powder in a case will make the difference in weight as its not a fluid and space between granules will vary?

Thats ts my point though about the other factors. If the brass is also inconsistent, as is the bullet searing depth then what part of it all has the greatest influence on improving accuracy as the powder charge does not seem to be the main contributory factor???

 

[nick100]

I have some Federal Power Shok ammo in 308W and they are all different lengths, and I mean different enough to tell by eye that they are varying.

I saw this too, different cal, but Federals.
It was one of the things that started me on reloading.

I am by no means the best shot in the world, but I feel more confident in my reloads than factory.
Especially if they are the same length.

 

[Orvil]

Factory ammo is loaded to volume. You can do the same and do just as well provided you are consistent. There are so many other important factors besides a few granules of powder.~Muir

Bit of a sweeping statement but yes... all factory manufactured (commercial and military) are made by volume measured powder throws. They'd never be able to keep up with demand otherwise. That will usually mean a variance of up to 2 grains of powder in larger cases (I've pulled certain brands and measured them 308 +). Just goes to show that all that tinkering and hours spent measuring internal case dimensions etc doesn't really amount to much when talking about "minute of deer". If you want to remove a mozzy's ********, that's where reloading comes into its own. Mega bonus is the satisfaction felt when one of your own home rolled loads hits the deer and knocks it over or drills a 1/4" group at 100 yards consistently.

 

[Muir]

Bit of a sweeping statement but yes... all factory manufactured (commercial and military) are made by volume measured powder throws. They'd never be able to keep up with demand otherwise. That will usually mean a variance of up to 2 grains of powder in larger cases (I've pulled certain brands and measured them 308 +). Just goes to show that all that tinkering and hours spent measuring internal case dimensions etc doesn't really amount to much when talking about "minute of deer". If you want to remove a mozzy's ********, that's where reloading comes into its own. Mega bonus is the satisfaction felt when one of your own home rolled loads hits the deer and knocks it over or drills a 1/4" group at 100 yards consistently.

Agreed. I'm not saying by any means that one can't do better by being consistent in powder charges, but that alone will not help much if other variables aren't controlled, and if you aren't going to bother with them, then you might as well load to volume and likewise not fret those missing tenths of a grain weight or a few thou in seating depth.~Muir

 

[Brithunter]

I suppose one should not be surprised that a lot of people seem to think the in the commercial production of ammunition they have a long line of scales weighing the powder ............................... just goes to show how people just don't think things through.

It also makes me wonder how many actually check the batch numbers on the boxes of ammunition they buy to check they are the same as those they previously had and if different do they actually check zero is the same?

So many simple basic things are missed out it seems.

Until I moved here I used an RCBS Uniflow measure, which now lays in a drawer since lack of space to mount it, so I bought a set of Lee Powder scoops and have been using them for my hand loading since. I check about 1 in 10 on the scales. Of course I am old fashioned also in that i also have proper paper reloading manuals and have read the articles in them plus others in magazines thus picked up some tips for using them.

 

[Muir]

I suppose one should not be surprised that a lot of people seem to think the in the commercial production of ammunition they have a long line of scales weighing the powder ............................... just goes to show how people just don't think things through.

It also makes me wonder how many actually check the batch numbers on the boxes of ammunition they buy to check they are the same as those they previously had and if different do they actually check zero is the same?

So many simple basic things are missed out it seems.

Until I moved here I used an RCBS Uniflow measure, which now lays in a drawer since lack of space to mount it, so I bought a set of Lee Powder scoops and have been using them for my hand loading since. I check about 1 in 10 on the scales. Of course I am old fashioned also in that i also have proper paper reloading manuals and have read the articles in them plus others in magazines thus picked up some tips for using them.

There is much of the old ways of doing things that is lost on newer shooters for the lack of looking away from the Oracle Internet. I remember the days of undampered scales. Would you want to weigh out every charge on one of those?? Not a freaking chance. ~Muir

 

[bewsher500]

I just loaded 50 .222 rounds
using scoops to throw the 22.6gr charge into the scale pan
very accurate with 3 out of 5 being bang on, others being .2gr either side
when in the case the levels varied between almost full to near the neck base!!
Can't win!!

 

[charadam]

I apologise if I'm stating the obvious.

Assuming the powder is of consistent "construction", if the volume in the scoop is the same, then the volume of the case must be the variable if the loaded case shows variance in the filled level.

In the case of the factory rounds, do the factories see the charge weight as secondary to the case volume as a way of controlling pressure?

In other words, do the factories care more about fill level rather than a charge weight?
​

 

[Muir]

I apologise if I'm stating the obvious.

Assuming the powder is of consistent "construction", if the volume in the scoop is the same, then the volume of the case must be the variable if the loaded case shows variance in the filled level.

In the case of the factory rounds, do the factories see the charge weight as secondary to the case volume as a way of controlling pressure?

In other words, do the factories care more about fill level rather than a charge weight?
​

It is the brass in some instances (Hornet comes to mind right off) but sometimes it's just the case needs a tapping top settle the powder.

As to your question: No. Charge weight is largely a matter of economics balanced with performance. Powder is purchased by the pound so they want to use the least powder they can, yet that consistently gives the performance they are after; what ever that might be. Loading by volume is also a matter of economics. Is it fast, inexpensive, and suitably accurate for the purposes. ~Muir

 

[Simjim33]

I use the dippers always. In fact the scales never get used!
But I use the dippers as a calibration tool for the lee powder through.
With this method you can load 100 rounds very quickly.
The lee factory crimp takes out any veriation in charge. I found my required accuracy noad was located with in +/- 2 grains! (1" groups if you want a range kind of measurement to understand.)

I would like one of those fancy Roberts powder meters that you have Muir.
But at £15~20 for a lee. I could buy one for each of the powders and changes I use and never need to reset them again!

But then again the 30-06 would have 3 just for that.

All of the above has to be looked at in the light that I stil can't reload cheaper than buying PPU factory!
PPU used to shoot 1" out of the old rifles.

I will just have to see if it holds true for the new rifle!
If not, back to reloading. What a chore!

 

[phaedra]

All of the above has to be looked at in the light that I stil can't reload cheaper than buying PPU factory!

Can I ask what calibre that's for?.

I load all my ammunition, for the .308 target it costs me around £40/100 using a high quality bullet (168gr Nosler CC) and brass (Lapua or RWS), PPU factory is £63/100 for the standard stuff and £75/100 for the "match" version.

 

[gixer1]

Can I ask what calibre that's for?.

I load all my ammunition, for the .308 target it costs me around £40/100 using a high quality bullet (168gr Nosler CC) and brass (Lapua or RWS), PPU factory is £63/100 for the standard stuff and £75/100 for the "match" version.

Does this take the cost of the equipment into consideration or just the components? I guess you need to split the equipment cost over all the rounds it makes.

i will say that if you include the time it takes (let's call it "labour") it really isn't that much cheaper than PPU and the factory ammo is pretty accurate now..

i think it's the enjoyment of reloading I like - and that's because I made it even easier with a lee loader.

regards,
​Gixer

 

[Simjim33]

Can I ask what calibre that's for?.

I load all my ammunition, for the .308 target it costs me around £40/100 using a high quality bullet (168gr Nosler CC) and brass (Lapua or RWS), PPU factory is £63/100 for the standard stuff and £75/100 for the "match" version.

30-06 =£56 per 100
.243 = £56 per 100
But then .243 is cheaper if I reload my home swaged bullets. Then it works out to 16p per round!
Problem is @ 68 grain, they are great for fox and munty and CWD.

Does this take the cost of the equipment into consideration or just the components? I guess you need to split the equipment cost over all the rounds it makes.

i will say that if you include the time it takes (let's call it "labour") it really isn't that much cheaper than PPU and the factory ammo is pretty accurate now..

i think it's the enjoyment of reloading I like - and that's because I made it even easier with a lee loader.

regards,
​Gixer

No I didn't include the tools. You have to buy them if your reloading. The lee loaders are all you need though! So reloading can be as cheap as you make it.

Injust don't have time to reload to be honest. If I did I would worry about seating depth!

To be honest there are far better uses of my time than reloading. When PPU gets to the price where it's not cheaper. I will reload again!

 

[phaedra]

Does this take the cost of the equipment into consideration or just the components? I guess you need to split the equipment cost over all the rounds it makes.r

Just the components and an amount for 10x case use but this can be cheaper with the subsonic loads as there's very little working of the brass.

I load for several calibres in different configurations,

.308 - Outdoor 100m+ Target Loads
.308 - Indoor 25m subsonic Target Loads

.300blk - Outdoor 100m+ Target Loads
.300blk - Indoor 25m subsonic Target Loads

.223 - Outdoor 100m+ Target Loads

.44 rem mag - Indoor 25m Reduced Target Loads

The 308 Outdoor Target loads will shoot at least 1/2MOA which is a lot better than I got with PRVI Factory Match ammo or using their 168gr Match bullets, the 300 & 308 indoor subsonic loads are really cheap to load

At a guess I'd say I load about 7,500 rounds a year so the savings pay for the equipment fairly quickly (most of it I bought in the US so a lot cheaper than buying it here).

 

[Muir]

I couldn't' afford to shoot if it wasn't for reloading. I'll say one thing about equipment: It isn't what you have, it's how intelligently you use it. When I forst started out I had borrowed gear, or cast offs that were donated to a teenager's cause. The un-dampered scale I mentioned earlier? Free. Awful to use but I was grateful to have it and made due with it. I weighed a charge, made a dipper to match from old brass and put the scale away. I didn't have a powder measure so this was it. Over the years I collected equipment. Some stayed around and a lot of it got given away or lent to people who still have it. All the micrometer seaters are gone except for those in the Lee Zero Error Target Loader. I don't think I have any of the In Line BR seaters left unless it is one I made for 218 Bee some years back. As the Marine PMI will attest, my reloading room is pretty basic. The cost of the remaining gear? I figure it's paid itself off years ago.~Muir