How accurate are factory powder charges?


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gspn
January 22, 2013, 03:50 PM
Anyone ever pull factory bullets and weigh for consistency?

I was just thinking about the best way to get consistent drops and it made me wonder how consistent the factory ammo is.

I currently use a Lee Classic Cast and Hornady LNL. The Lee is pretty good with the auto-disk measure...and I got the micro-adjust inserts for the LNL so it's pretty good too...although neither are spot-on every time.

I guess I might be too picky but when I want to throw 71 grains of powder...I want 71 grains...especially when working up a new load. So what I normally end up doing is dropping a charge that is as close as my gear can get it...then adjusting by hand.

Anyway...was just wondering if anyone knew how consistent the factory folks try to get it.

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ironworkerwill
January 22, 2013, 04:00 PM
Winchester did a good job on the 25wssm factory ammo. I shot it out of a browning a-bolt and it was hard for me to beat factory loads in the way of accuracy. so, I'd give the answer of "It depends". But I have bested lots of other ammo. That being said I've never weighed factory powder for consistency.

Captcurt
January 22, 2013, 04:58 PM
I am with Iron worker here. I bought a new Weatherby Vanguard that shot under MOA out of the box with Weatherby factory ammo. I finally found a handload that will do it but it took some serious load developement.

Rule3
January 22, 2013, 05:25 PM
I would have to say the major makers would be spot on. They have the best equipment and being big business every tiny grain is money as it adds up doing a bazillion rounds.:)

Steve C
January 22, 2013, 05:42 PM
Large manufacturers do not load using canister grade powder, instead they use bulk powders that do not have normalized burn rates like a canister powder will have. They determine the load for a particular container of powder in their lab to achieve the pressure they want. That powder and load is then used in one or more loading machines and other containers with a different determined charge weight may be used in another machine or the same machine at a different time to load rounds of the same caliber and bullet weight to the same pressure specs.

The ammo is not segregated by powder charge but is batched processed, rounds are mixed as they proceed through different processes like cleaning and polishing and then placed into packaging so many different charge levels could possibly be found in the same box of ammo yet each round will have a consistent pressure, velocity and level of accuracy. If you are interested you can randomly select different rounds from factory loaded ammo and may find different level of charges but that doesn't reflect on the consistency of the ammo.

gamestalker
January 22, 2013, 06:35 PM
Honestly, when I started reloading about 3 decades ago I did just that. I pulled a bunch of factory apart, handgun and high powered rifle both, and the variance from one round to the next was quite large. Although that was over 30 yrs., ago my Son did pull down some recent factory rounds and the charges were still pretty inconsistent. I never kept any records, but from memory I do remember that the powder charges had a spread of more than 10% with some even worse than that.

All part of why I'll never go back to factory for any of my shooting needs.

GS

ranger335v
January 22, 2013, 07:16 PM
Can't you just imagine the cost of factory ammo if the makers tried to train enough monkeys to weigh each charge within tenth of a grain! Won't happen, factorys run production lines so fast it's not easy to even see cases getting their charges dropped straight from high speed powder dispensers.

Factory ammo is quite variable by what reloaders expect, including so called 'match ammo', but if a rifle likes factory stuff it's hard to equal, never mind beat, with handloads. All going to prove that the precision charges so many feel just HAS TO BE critical for accuracy really isn't very critical at all! :eek:

Anyone doing a pull-down test of factory charges will find the range will vary a lot by case size, smaller charges will have smaller variations but the percentages of variation will be about the same.

Adam the Gnome
January 22, 2013, 07:25 PM
I weigh about three hundred charges in a row to get my uniflow set. After that I don't worry, unless I'm near max loads. Then it's just every 15 or so charges

I'm sure big time factories set the machines once.

tightgroup tiger
January 22, 2013, 07:39 PM
When I'm at the indoor range I shoot at, in the lane next to me I can tell whose shooting cheep factory pistol ammo from the change in pitch between shots. They also have a large rubber mallet and aluminum ram rod behind the counter for pounding squibs out of their own guns.

They sell name brand factory ammo, not their own reloads.

They can't be very consistent. I've never bought a box of factory rifle loads so I don't know about them.

GaryL
January 22, 2013, 08:06 PM
Large manufacturers do not load using canister grade powder, instead they use bulk powders that do not have normalized burn rates like a canister powder will have. They determine the load for a particular container of powder in their lab to achieve the pressure they want. That powder and load is then used in one or more loading machines and other containers with a different determined charge weight may be used in another machine or the same machine at a different time to load rounds of the same caliber and bullet weight to the same pressure specs.

The ammo is not segregated by powder charge but is batched processed, rounds are mixed as they proceed through different processes like cleaning and polishing and then placed into packaging so many different charge levels could possibly be found in the same box of ammo yet each round will have a consistent pressure, velocity and level of accuracy. If you are interested you can randomly select different rounds from factory loaded ammo and may find different level of charges but that doesn't reflect on the consistency of the ammo.

This is correct. I used to install specialized automation equipment, and have been to many different types of factories across the country, including a major ammo manufacturer. I have walked by large metal bins of handgun ammo staged and waiting for packaging. I think most people would be surprised at how consistent any given machine can be from one round to the next. However, and this is really the key, factory ammo is loaded to a specification, and it's quite likely your firearm doesn't care for that specification. But the factories have test rigs and do quality control testing to verify their loads are consistent.

It's possible some have moved more towards single piece flow than in the past, but that doesn't preclude mixed lots as some processes really are batch oriented.

Yarddog
January 22, 2013, 08:23 PM
Well in the early '80s I've shot the cheapest factory ammo around out of my Rem 700 30 06.. I shoot sub MOA most of the time... Every now and again I'd have a flyer out of the 5 rounds that broke the MOA not by much 1.250 would be about max & I considerd
that pretty good,, For hunting that is ; ) JMO

Y/D

TNBilly
January 22, 2013, 08:36 PM
Originally Posted by Steve C
Large manufacturers do not load using canister grade powder, instead they use bulk powders that do not have normalized burn rates like a canister powder will have. They determine the load for a particular container of powder in their lab to achieve the pressure they want. That powder and load is then used in one or more loading machines and other containers with a different determined charge weight may be used in another machine or the same machine at a different time to load rounds of the same caliber and bullet weight to the same pressure specs.


This is true in my experience - I've found up to 3 grains variance on one load I checked out.

beatledog7
January 22, 2013, 09:59 PM
If factory-loaded, high-production-volume ammo is as consistent as handloads, why don't the top competition shooters use it?

FROGO207
January 22, 2013, 10:24 PM
The real way to find out if it is consistent is to measure the velocity of the rounds and average the results. Then load up some for yourself and see how your results compare with theirs. I also can tell when someone is shooting cheap factory ammo as the reports from a box of ammo can sound lots different, mine all sound similar to my ears however. YMMV

GaryL
January 22, 2013, 10:37 PM
If factory-loaded, high-production-volume ammo is as consistent as handloads, why don't the top competition shooters use it? I think you are confusing consistency with accuracy. The factory's goal is a stated velocity within some SD, but more importantly, within a pressure spec limit.

As others have stated, it matters not if the powder of the day requires 15gr or 20gr to pass muster in a test rig. Depending on the caliber, they are also having to maintain their specs across dozens of different machines in various states of condition. Machine C could be literally brand spanking new, and the one next to it 50yrs old, 10 years from it's last tune-up, and due for a total overhaul. As long as everything is in spec, it's acceptable, but a handloader would never tolerate those variances.

jerkface11
January 22, 2013, 10:46 PM
Volume of powder is more important than weight.

beatledog7
January 22, 2013, 11:16 PM
I think you are confusing consistency with accuracy.

From my study, I've learned that consistency = accuracy.

The factory's goal is a stated velocity within some SD, but more importantly, within a pressure spec limit.

The factory's primary goal is law suit avoidance. Everything else is secondary.

Dthunter
January 23, 2013, 03:56 PM
I know I dont shoot factory ammo for a couple of Reasons.

1.) Its not as consistant,accurate, or at The velocity ranges I want with my Rifles.(year in/out). One batch of factory doesnt shoot the same As the Next.

2.) I can tailor a Load to my rifles preference, and load as many as I like,when I would like to.

oneounceload
January 23, 2013, 04:13 PM
Their powder drops are only as accurate as gravity combined with the speed of their machinery can attain. This isn't like a high-speed factory loading ketchup bottles where they can force the material into the bottle. But they still get it pretty darn consistent

Nalgi
January 23, 2013, 10:30 PM
in a recent handloader magazine they attack that subject. Pretty interesting results.

Summary- doesnt make a lot of difference, there is more room than you think

ljnowell
January 23, 2013, 10:36 PM
I see a lot of people suggesting manufacturers would be very accurate with powder charges. This has not been my experience though. I shoot at the winchester handgun facility in Alton IL(Olin range) in leagues where we use thier ammo. Using match wadcutters you could feel the difference at times. We took a box of 50 of them and found variations by as much as .3 of a grain. I would say that my wadcutter loads are much more accurate weights, never more than a .1 and usually right on the money(I use AA2 which is super fine and meters superbly.)

Andrew Leigh
January 24, 2013, 01:35 AM
A friend tells a wonderful story of being on the range with local factory ammo in 30-06, he was shooting at 100m over the bench and could not manage anything better than 1.5" groups.

Someone had mentioned to him that a South African Junior Champion (forget which discipline) was also shooting. So off he trundles and asks the youngster to please shoot a group for him to see if it was the rifle, the ammo or indeed his lack of ability.

Three rounds later the Junior Champ had a very nice and very tight clover leaf.

bfoosh006
January 24, 2013, 02:16 AM
Given the volume of ammo loaded by Manufacturers.... this thread has now made me wonder How they can be as accurate with charge weights as they are ?! Off to youtube for some kinda video .

fguffey
January 24, 2013, 10:32 AM
Yes I have, seems there was a shooter at the range with a new rifle and new ammo, 5 rounds of 20 Remington 30/06 did not fire, everyone at the range with a 30/06 had a chance at it, nothing worked (long story). That afternoon one of the shooters at the range came over with 15 fired and 5 rounds with hammered primers. I suggested calling Remington, I suggested calling Ruger, I suggested saving the box the 30/06 came in, nothing, my friend did not get the name of the proud owner of the rifle.



We pulled the 5 failed to fire rounds rounds, we weighed the cases, powder and bullets, we saved the primers, we checked the fired cases in a chamber gage, Wilson case gage, etc, the fired cases chambered in my chamber gage with slight thumb pressure, we measured case head protrusion from the gages, nothing suspect. We then installed the primers back into the cases they were removed from, we chambered the cases with dented primers in one of my M1917s one at a time, all the primers fired when the firing pin struck them.



Back to "YES I HAVE", my friend did not like my scales so I set up the RCBS 10/10 for weighing the components, we were impressed, there was not 1/10 grain difference between the weight of the bullets, powder or cases.



The primers were hit 5 times in three different rifles, there is nothing timid about the firing pin strike of the M1917 I used, I have another M1917 that has a short hook up between the cocking piece and trigger, that one is slightly different in a lot of ways.



F. Guffey

HighExpert
January 24, 2013, 05:25 PM
I have chronoed a lot of factory ammo as well many handloader's ammo and what I find is about 40% of handloaders can best or equal the standard deviation of "good" factory ammo. Velocity is not the be all end all. If your ammo is not consistent it is junk. When I load match ammo for bullseye competition I work for an SD of 4 or less. Some cartridges just won't get there and that is when I start looking for different brass, bullets, or powder. I have rarely seen any big difference with various primers. With rifle, you also have include bullet alignment, seating depth, case prep and neck pressure along with the aformentioned. Rifle ammo is 50% science and 50% voodoo. You can have a perfect bullet and it won't shoot worth a darn. Change one component and...presto.. the magic happens. That is the reason for handloading. You have control of the tiny changes. Too many folks are not picky enough and lack the patience to really wring all the accuracy out of their guns and ammo. For them factory is probably "good enough".

gspn
January 24, 2013, 05:32 PM
I have chronoed a lot of factory ammo as well many handloader's ammo and what I find is about 40% of handloaders can best or equal the standard deviation of "good" factory ammo. Velocity is not the be all end all. If your ammo is not consistent it is junk. When I load match ammo for bullseye competition I work for an SD of 4 or less. Some cartridges just won't get there and that is when I start looking for different brass, bullets, or powder. I have rarely seen any big difference with various primers. With rifle, you also have include bullet alignment, seating depth, case prep and neck pressure along with the aformentioned. Rifle ammo is 50% science and 50% voodoo. You can have a perfect bullet and it won't shoot worth a darn. Change one component and...presto.. the magic happens. That is the reason for handloading. You have control of the tiny changes. Too many folks are not picky enough and lack the patience to really wring all the accuracy out of their guns and ammo. For them factory is probably "good enough".
Great post. I'm going to steal that line that rifle reloading is "50% science and 50% voodoo". Too funny.

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