I am in the process of getting set up for production loading of some 5.56/.223.
Brass: LC new (2k) and once fired, various lots (3800 rounds)
Bullets: Hornady 55 gr. FMJ Spire Point flat base w/ cannalure, and 77gr. Sierra Match King HPBT
Powder: AA2230
Primer: CCI Small Rifle
Going off of Accurate Powders latest load info - for this example, the Sierra MK 77gr.;
Min 20.0 - Max 22.2.
Sierra’s manual (5th edition) for AA2230;
Min 20.9 - Max 23.4 - with a warning “Loads less than the minimum are not recommended”
I know this is all going to come down to crono and accuracy testing to find what works best. I have 10pks loaded up in .2gr increments waiting for an opportunity to go test, but I want to wait for my case gauge to come in first (on backorder) to make sure my sized cases are good. They were trimmed to 1.752 +/-.002 but I am unsure of the shoulder. It’s going to become a priority to get my 55gr. loaded up real soon, like 3 weeks (I signed up for a training class, there went my private range membership money).
SO…What how do you people deal with conflicting load data? I’ve read other info and threads that have the same type of conflicting info, and a great many user submitted recipes (same powder and bullet) that way exceed the max load, usually by at least 2 grains of powder.
Maybe I am over thinking this. I do see an inherent problem with the various companies and load data keeping up with the types of rifles being shot. Barrels are getting shorter - all the reloading info I have seen are 20" or longer, at least Accurate Powder gives a math equation to adjust for barrel length in velocity -, 3 different length gas systems (that’s got to have an impact on the performance) different chambers…
And after near 2 hours of using the SEARCH button, even those using the same powder and other components for the 55gr that I am are running an average of 1 grain over the published max loads that I have found, some as much as 2.5.
Generally if the load is slightly underpowered, you’ll see less brass expansion. This will result in less of a gas seal, and your brass will eject with a blackened and dirty case. However, if you are shooting it out of an AR, then it may not even cycle the action.
The trick to loading anything is to look for those signs with each piece of brass fired until you have determined that there are no signs over underpressure, and no signs of overpressure. If you don’t know all the signs, then get a copy of The ABCs of Reloading which goes through those signs.
Lots of manuals have slightly different min and max charges. Many things can effect pressure and give slightly different results. The chamber and bore of the rifle, the age of the rifle, the hardness of the bullet jacket, undercharging so that you get “detonation” effect, elevation, air pressure…etc. So, naturally there will be some slight variations between the manuals. Generally they test beyond their max loads safely, but they publish a lower max load to compensate for the many variations. This is why factory ammo is generally lower powered than boutique ammo venders like Double Tap…to keep it safe under the widest range of conditions.
Not every loading manual uses the same gun for testing. Some use a real firearm, some use special “test barrels”. There may also be chamber differences when using a real firearm (for example, one may use a Colt that has a 5.56 chamber and one may use, saym Armalite or BM or something that probably has a .223 chamber). And their testing is not at the same altitude and pressure and temperature as their competitor and that affects the results as well.
This is why I like, personally, to have as many loading manuals as I can afford plus the powder companies’ online offerings so I can cross reference and compare. If one company’s loadings are wait different but the rest are substantially similar, that is what they call “a clue” (to a t least try and figure out why).
What I have done in your situation is to load one cartridge at the starting load from one of the load books. Then increase the powder charge 0.2g one cartridge at a time until over the max load in the book.
Then shoot (from low to high) over a chronograph at 200y marking each bullet hole until I either get to the last round or start seeing pressure signs or get the velocity I want.
Analyze the target to see where my accuracy node is and load a few groups of 5 or 10 rounds to see if it is repeatable. If it is then load a lot of it.
One other reason you might run across a load that seems to be out of the ordinary i.e. low in velocity or on charge weight is because it may be designed not to cause unnecessary pelt damage. Small hole in and small hole in.
Well, whatever the reasons are, it is still frustrating to find such a wide disparity in powder weights among the “industry”, and the first rule for reloading that everyone pounds their fist on is “Never exceed the Maximum charge weights”.
I get the legal aspect of it all (let’s not wander down that road).
If I don’t get an opportunity to test my loads soon (I am at the mercy of the charity of others - I have no range membership) I am going to have to start a new thread for recipes that others are using to get my ammo made up for my class in March.
…and the first rule for reloading that everyone pounds their fist on is “Never exceed the Maximum charge weights”.
That’s never a bad idea, but many experienced reloaders exceed “some” book maximums at times. Key word here is experience. I’m over max on my .308 bolt gun load, as well as slightly over in my 77 gr SMK load. That’s in a 5.56 NATO chamber, of course. But then I’m well under max in various other loads.
It’s been explained why the loads vary by source - this has to do with the maxim of “working up your loads” as well as lawyers. But I disagree with taking it 0.2 grains at a time - hell, my powder drops will vary by that much! (And I almost never start at the bottom.)
If I don’t get an opportunity to test my loads soon (I am at the mercy of the charity of others - I have no range membership) I am going to have to start a new thread for recipes that others are using to get my ammo made up for my class in March.
I think you might have he cart before the horse here, but that’s just my opinion. Easy access to a practice range would be tops on my list of priorities.
You think that would be easy along the Front Range of Colorado around Denver. Not so much. 1 public outdoor range, 100y max, expensive and annoying, and typically overcrowded. BLM land shooting areas are up in the mountains and currently under a few feet of snow. Everything else is indoor, minimum $20 an hour, and I don’t know that any of them would allow me to set up a Crono slightly down range.
The cart was behind the horse where it was supposed to be until I blew my private range membership money (the only one that does not have a 2 year waiting list and regrettably is 1.5 hours from my home), and spent it on a training class in March.