4350 powder

toad67

I know that both H and IMR are not interchangeable but can anyone tell me why the numbers are the same from different manufacturers and how close are they?? Thanks.

Todd

Pearyw

They are almost the same, But you need to work up your loads individually.

gunnut505

They have to make an easy-to-understand comparative sound-alike to indicate its' relative burning rate or intended use; this by no means indicates that certain products are interchangeable, by weight or volume, in any way whatsoever.
Then there are the oddballs; AA#5, HS-7, BLC-2, Reloder22, H-110, etc. that have a characteristic burning rate all their own, or are suitable for certain other uses.
The only way to determine how to suit your particular situation (saving money, shooting a match, using up the last of a keg/box of bullets) is to study the desired calibers' loading data from a RECENT source, keeping an eye on the outcome you prefer (easy cleaning after shooting Wadcutters, higher velocities for less holdover, targets at long range), and load those recipes that meet your criteria with the powders listed in the manual.

Ambrose

Accurate Arms also has a 4350 and there used to be one called Brigadier 4351. FWIW, I did an experiment one time with identical charges of the 4350's and 165 gr. Nosler ballistic tips in a .300 H&H magnum:
AA4350 = 3184 fps
BR4351 = 3142 fps
H4350 = 3199 fps
IMR4350 = 3220 fps
Chronographed several 5-shot groups with each load. Got good accuracy with each powder.

Rocky Raab

The best description I've read for this "same number, different company" situation is that you should consider them as fraternal twins: NOT identical, but closely related.

You can apply that analogy to the pairs of 4227, 4198, 4895, 4064, 4350 (triplets!), and even 4831.

There are pairings that ARE identical twins, but none of them have an IMR half. The identical twins are: W541/HS-6, W570/HS-7, W231/HP38, W296/H110, and W760/H414.

One that many think are the same are actually NOT, and those two are H335 and W748.

jonk

While they aren't interchangeable, for most applications they are close. For instance, H4895 and IMR 4895 aren't identical, but since most of my loads are about 4 grains off the max, I don't worry about it- I just load up 44 gr of it for my 30-06 guns with a 150 gr bullet. Around 49 would be max. But they do produce slightly different velocities and usually slightly different accuracy (sometimes in group size, more often in point of impact)

sandwarrior

toad67,

As all have noted here it's about having a close alternative to what you're working up. At the bottom end it gives you somewhere to go without having to wildly guess and by golly what to start with. On the top end of the pressure spectrum it gives you either a smidge slower burn for more pressure at the end of the barrel or or faster so you're not blowing pressure out the end of the barrel. A tad more pressure for one type or less for another. This and a change in primers or cases makes a great way to tune a load to a firearm.