Home Forums Hunting & Shooting Ask The Gunwriters Switching I4350 to H4350

Gentlemen; I am sure this has been covered here before but my searches have not turned up an answer.

With the ongoing component shortage I have been unable to source any I4350 but I have been able to get 3 pounds of H4350. As always any change in components will demand a reduce powder charge and work up process, but is there a standard relationship between I4350 and H4350 that I should be aware of?

Thank you in advance for your responses.
GRF

Not really. It depends on the particular lot of powder, and the particular cartridge/bullet combination. These days they're generally very close.

Another powder you might try in that burn-rate range is IMR4451. I've gotten fed up with trying to find enough H4350 these days, but IMR4451 is very similar, and very available. I've been able to work up loads easily in every cartridge where I used to automatically reach for IMR4350 or H4350.

The primary concern at the moment is a .260 with 120 grain bullets.

I have not seen any IMR4451 up here at all and was pleased as punch to find any H4350 or I4350.

Thanks for your response. GRF

Thanks for that--didn't know about 4451--am glad I am not the only one getting fed up with all this just-in-time crap...

Yeah, I've been experimenting quite a bit with both IMR4451 and 7977 lately. They're not on all store shelves (though they're showing up more and more), but just about every Internet site has 'em, and even with the hazmat shipping fee a jug can be purchased for a per-pound price that matches or beats most store prices these days.

IMR4166 is another good powder, with a burn-rate close to IMR4064, but that means it's also in the same basic range as TAC, IMR4895 and Reloder 15, all of which seem to be pretty available now. But IMR4451 and 7977 are definitely filling a need.

Thanks Jon--did you happen to run it in the 7x57?

Been on h4350 for 150s and am low on supply

No, I haven't but am sure it would work. It works perfectly with 165's in the .30-06, one of the classic uses for either 4350.

We've shot a couple hundred 123s outta the .260s with IMR4064 lately. Somewhere in the 37-40 grain range has been good in a couple rifles now. I've shot them below freezing and shot some yesterday when it was 95 without any noticeable shift in POI. IMR4064 is available everywhere.

I also have found IMR4350 pretty much everywhere. I have not found it to be nearly as 'temp sensitive' as most would imply.... funny how those old wives tales seem to propagate.

IMR4350 isn't too bad at different temperatures, band a lot better than some other powders. But a lot depends on the specific application, as it does even with the least temp-sensitive powders.

In some of my tests IMR4350 lost around 75 fps from 70 F. to zero with 165-grain bullets in the .30-06, but only 30-some fps in the .375 H&H with 300's.

Yep.... I think load density is the single largest factor in "temp sensitivity" of powders...

No, it's not, but it is a factor.

Sort of sliding away from the topic, but the old, standard, drop back 10% whenever making a change of any sort, from a different powder lot to having your hair cut, always seemed excessive to me. I am not advocating blowing up any firearms (in earlier years and for some individuals termed "experimenting"), but dropping from 57.0 grains of H4350 with a 180 grain bullet in an '06 to 51.3 always seemed a bit extreme.

Here's a thread from the past that I posted about that very subject...got some good answers. Hope this helps:

https://www.24hourcampfire.com/ubbth...itching_from_IMR._4350_to_H_#Post8070644

thanks John

I just wish some of the shops around her would get some Big Game in stock.

Most reports are that they are so similar they're interchangeable, but in the cartridges I've tried, I can never get as much velocity out of the H4350 before pressure gets too high--seems spikier.

Availability issues had my trying AA4350, and that might be my new favorite. It seems very similar to IMR, but meters much nicer. Not exactly your chambering, but I last used it in a 25 Souper with 100 grain SMK's, and I just kept adding powder, and it kept producing nice groups at 200. My bottles also indicate it's made in Canada, might be fairly available to you.

The Hodgdon load data has H4350 at 43.5gr 2814fps 51,400psi for a starting load, and 46.5gr 2960fps 58,200psi for max load with 120gr bullets and 24" barrel.

The same source has IMR4350 at 43gr 2885fps 58,000psi for a max load but doesnt list a starting load.

Load data from Nosler lists IMR4350 at 41.5gr 2796fps starting load , and 45.5gr 2979fps max load with 120 gr bullets and 24" barrel with no pressures listed.

MD, Since I know you and your better half both shoot 243's, have you noticed much difference between summer and winter velocites/POI's using IMR4350 ? Ben

I echo the thought on Big Game. Haven't seen anything Ramshot related in years.

Desperately need some BG for my 7-08.

I got lucky today at the LGS. Bought a 22 mag RAR on sale and also snagged 2 pounds of H4350. I'll go back tomorrow and snag the other 2 . My supply of H4350 was non existent and down to 7 pounds of IMR 4350, so I went back to using the IMR. I do prefer the Hodgdon powder though since it isn't as temp sensitive and it meters better through the uni-flo...