Why work up your loads? Why down load to start?

[Okie1907]

Ive always followed instructions and loaded down for my first 100 or so rounds before I do exactly what my book says but never wondered why. I just thought if my gun could shoot it and I didnt see anything wrong it would be fine to go to what the load data in my book says. For instance the book I am working out of says load down 10% before doing printed data. Why do that? If it is printed it is safe and probably already loaded down anyways.

 

[NightShade]

Every rifle is different and that is in multiple ways. Tooling wears over time so a brand new chamber reamer will be slightly smaller than one that is near the end of it's life. The newer chamber will be slightly thicker walled but will also have increased pressures. It's just better to check things out and see how it works before you go gung ho. Plus some weapons/ammo combinations will be more accurate. For instance and AR that has a barrel that is 1 in 9 may need a slightly faster round to produce an accurate shot vs a 1 in 7 with the same bullet.

If all you are doing is shooting paper it's probably best to run with something that is under maximum, all you care is if the chamber seals and the bullet fires reliably right. Why load a maximum charge to do that when you could save two or three grains per round? It may not sound like much but 3 grains every hundred rounds gets you a decent number of rounds you could potentially load. How about after 1000 rounds loaded, almost half a pound of extra powder to use. It all adds up over time, and while your savings will be less in a pistol sometimes as little as a tenth of a grain I look at the long run of things. Plus a lighter load will allow you to practice more on the actual shooting than recoil management not to mention less wear and tear on your weapon.

 

[swampratt]

The rule of 10% down to start will sometimes get you into trouble as this will be too little of a charge.
I see what you are saying that if the load is printed it should be safe.

max load Not always,, it is close to safe if you use the exact components they did.
Then there are differences in batch numbers.

If you substitute a different case or different batch number case,, if your chamber is not exactly the same as their chamber.

I still start my loads a bit above the minimum load data.. unless the load data is 25gr minimum and 26 gr max then i start at 25 or possibly 24.5 to see if there might be something there.

A lot of the book print is to cover their arse.. if they did not say start low and work up .. I would bet someone woud start at max blow up their firearm and sue the publisher.
Most of the print for 30-06 in my opinion is for older weak action firearms.
Liability issues there if you published 65K PSI loads for the 30-06.

You must really think things through. after you have been reloading for multiple firearms for some time you will understand why books say what they do.

 

[Rod Snell]

Sometimes the generic "load down 10% from max" does not apply to a specific powder/cartridge combination. For example, the well known WIN296 powder in pistol magnums carries the specific warning NOT to reduce below the listed data because there have been problems with reduced loads. It pays to read the fine print and know the specifics of the components being used.

And as swampratt noted, changing any component from what was used in making the table potentially changes the pressure, and whether this matters depends on the specifics of the components, and how close you are working to max pressure already. My homely analogy for new loaders is that if you are standing 10 feet from a cliff and take a step closer, no problem, but if you are only a foot from the cliff and take another step,,,,,,,,,

So, in regards to your Poll choices above, IT DEPENDS

 

[Toney]

I wonder if the 10% rule is to cover their ask in case of misprints.

The universal clays load in my 5th edition hornady book was insane.

A man needs more the one reference. ..

 

[OKCHunter]

I always work up loads for my rifles. Unfortunately, most of the loads are best in the upper ends of the recipe which means a little more kick and a little more powder needed. For hand guns, the bottom of the recipe range works fine for plinking accuracy. I usually just load up a few at or just above the bottom and go test for cycling and consistency. If I get a decent grouping, I call it good and go into production.

 

[mr ed]

You should always use an up to date book. If you used one from say 1973 and it says max load 25gr. of 2400 and the new book says 21gr. They may have changed the powder formula and the results could be terrible. Some of those freebie loading pamphlets just have 1 load and tell you to back off and work up.

I usually start at the bottom and work up because if you build 3 guns exactly the same, they all may not like the same bullet/powder combination.

 

[Okie1907]

You should always use an up to date book. If you used one from say 1973 and it says max load 25gr. of 2400 and the new book says 21gr. They may have changed the powder formula and the results could be terrible. Some of those freebie loading pamphlets just have 1 load and tell you to back off and work up.

I usually start at the bottom and work up because if you build 3 guns exactly the same, they all may not like the same bullet/powder combination.

How many rounds do you shoot before you load up? What are you looking for?

Like I said before I usually shoot 100 rounds if that if I'm just changing bullet but not the weight.

 

[mr ed]

How many rounds do you shoot before you load up? What are you looking for?

Like I said before I usually shoot 100 rounds if that if I'm just changing bullet but not the weight.

To me group size is more important than speed.
I once had a 1970's Remington 700 varmit in 22-250. factory ammo was 4" at 100 yds. we tried all kinds of combos with that gun. Finally we found a load nowhere near the top end using Nobel Powder, a Sierra bullet and setting the bullet all the way against the rifling.
It would then shoot unbelievable groups.
I usually load 100 rounds in 20 round 1/2 gr increments. then when I narrow down the 2 best, I load 100 rds in 20rd. 1/10 gr increments.

 

[Larry Morgan]

I don't know that I've ever gone 10% below the listed, but I definitely don't try the max load first. I usually start at or towards the lowest listed and try increasing amounts. 10% below even the max usually seems unnecessarily low IMO.