I have got a pound of imr 4451. With things they way they are (Powders hard to get and if you get them you pay a war price). I would like to use it in loading some for .308. Cannot find any loading data for that combo, what I have heard is that it is similar to H4350.
My question is has anyone used it, any source of reloading data available, some have said it can be used grain for grain replacement for H4350?

I’ve used it in the 30-06. I think it would be great in 6mm, 257 Robert’s, 270, 280 etc.

Might be a little slow in the 308. But might work very well with heavier bullets.

Hodgdon doesn't list data for it in 308 Win. Maybe a bullet manufacturer would in their data, though, since it is listed for 243 and 7mm-08 via Hodgdon.

It does say right in the description density and charge weights are different than 4350, though.

https://shop.hodgdon.com/imr/imr-enduron-4451

Yeah, that's the thing they list it for all the calibers that have a .308 parent case, so why not do the obvious and work up the .308

It's not just the size of the case that matters. The relationship of the size of the bore to the case capacity is very important.

I looked on Loaddata they didn’t show any loads with the 308 and IMR4451 or IMR4350.
It’s slow powder for that cartridge.

If we lived close I’d trade a medium burning powder for it.

If I were you, I’d save that powder for a better matching cartridge and buy something in the 4895’s burn range. It only hurts once, paying the new prices that is.

I dont think it will work very well in 338 Federal or 358 Winchester.

It is NOT grain for grain interchangeable with any of the other 4350s either. At least not the lots I've worked with. Close only counts in horseshoes & hand grenades.

Hodgdons says it’s the same as H4350

But, I’d never load H4350 in a 308

That doesn't read "the same" to me.

The source is this link

Comparable in application, yes.

Yeah I've always had good luck with 4064 and 308 size cartridges was just trying to make do use some powder I had on hand

Sierra has data for it. Max velocities aren't quite as high as Varget or RE15 and it is most assuredly not grain for grain with either of the 4350s.

ask Hodgon for data with specifically what bullet(s) you plan to use. I bet they will respond.

IMR 4451 and its close relative IMR and H 4350 are just too slow for the 308. I just checked the Hodgdon site and they don’t have any data for any bullet weight in the 308.