Originally Posted by 416RigbyHunter
Originally Posted by antelope_sniper
Originally Posted by 416RigbyHunter
My experience is different to the powders recommended so far.
Since I got my first 338, the ONLY powder that gave great accuracy has been RE19, the best part of that is the fact it runs 100fps faster than any other powder I tried behind the 225gr Accubond. I ran with a load in either Win or Rem brass, WLRM primer and 76gr of RE19 with 225gr Accubonds, this gave me 2890fps in a 26” barrel and 2820fps in a 24” barrel.
With 200gr bullets and lighter, 2 powders stood out for me, Win 760 and H4350.

Picking a powder is not governed by barrel length, it is governed by what performance you want.
For me, I look at several manuals, starting with the bullet manufacturers data, then look at several other sources and look for the powder that provides the HIGHEST velocity across all those sources, then I evaluate IF it is going to be sourcable, as Alliant powders here are impossible to get, then I will select the three TOP powders across those manuals that are the highest velocity providers. The reason for this is because those powders are the most suitable in efficiency for that expansion ratio. Then I will load 3 cases starting at 5% reduction from max and work up in 1gr increments and shoot groups, choose the tightest group and then do a ladder at 300mtr with +/- .3gr increments.

Originally Posted by antelope_sniper
I'd start with H4350

With my 26" barrel, I've had good luck with both H4831 and H4350. With shorter barrels it preferable to favor the faster powder, but no need to go crazy far in that direction. Just stay off the crazy slow for caliber side of the burn chart and you will do fine. The slowest powders for caliber produce the best velocities in longer barrels.


This statement about faster powders being preferrable in short barrels is complete BS.
The powder that provides the FASTEST velocity in a LONG barrel will also be the powder that provides the fastest velocities in a SHORT barrel.

It is time for this MYTH to be buried forever, it is simply false and misleading.


You are factually wrong. Long barrels favor slower powders, but so slow enough and they will plateau in shorter barrels before reaching maximum powder charge. By the same token, you don't have to go much faster to mitigate this effect. As I mentioned above, a small change, such as going from H4831 to H4350 can be enough for proper mitigation.

I totally disagree with you.
Having a pressure trace shows me barrel length has nothing to do with slow or fast powders being preferred in short or long barrels.
Max pressure and burning of the powder occur within an inch or two of the case mouth, the burn rate doesn’t change this, all that changes is the TIME under maximum pressure, which is governed by burn rate, not barrel length. Even with a 16” barrel, the slow for calibre powder will have higher velocity than a fast for calibre powder. The reason is simple, the slow powder pushes the bullet for a longer time. Period.
Many believe that a faster powder will provide MORE velocity in a short barrel due to time, this is simply false, as a sloww powder expands for a longer time, even in a short barrel.



Unless my chronograph was lying to me (which I doubt), I've seen this phenomenon in the real world.

Why most people such as yourself don't believe it's because they are not using powders at the bleeding edge of slow for bullet weight, with compressed loads. It occurs in a narrow window, which is probably why you've failed to capture it in your limited testing, but it's still there.

As for the math and taking the integral of the quadratic to derive the area under the curve, so you're not telling me anything I don't already know, but there's additonal forces you are not accounting for, which is why experimentally, you are wrong.

You didn't use logic or reason to get into this opinion, I cannot use logic or reason to get you out of it.

You cannot over estimate the unimportance of nearly everything. John Maxwell