Gotta take the fun out of it...IMR4350


Well-Known Member
Haha,y'all know "that guy" who takes something like fishing with a Gbaby which should be a rather simple affair and turns it into some bass pro event?

Well,trying NOT to do that.....

First,I'm also NOT trying to "reduce" IMR4350. My question is however,why not? I need to know... is it, S.E.E. ? And if so.... why does 4350 get "picked on"? Isn't it just another extruded,sort of slow burning powder?

On my 100g varmint blaster 7-08 I have 2 powders lined up.... Varget,and H4895. Good stuff,on paper. These will be right at starting JB,book....loads. The deal is,I've had very good success over the last 40 years with IMR4350 and 243's and 6mmR's. To the point of it/them being essentially one bullet,one load rigs. And occurs with enough frequency that it sorta sticks in your grey matter.

So,am seriously considering using this 4350 for the 100g 7mm's. Just trying to wrap my brain around why all the warnings about not reducing it? And again..... I don't "want" to reduce it,instead....would rather be well "up into it" looking for velocity.
Last edited:


I use IMR ,H and AA4350 a lot in my rifles and have found the same thing. I use it in 30/06, 270, 300WM and 243. I like it so much that I always look to see if it is listed for any new rifle.


North Central Arkansas
I've reduced AA4350, in my 338 Win Mag with 200 grain cast, without any issues. It's not a ball powder, like AA2520, so SEE shouldn't be a problem. Accurate's Red Manual is where I got the reduced loads for the belted magnum. On the other hand, Accurate gives no reduced cast loads for AA2520. I was warned off reducing AA2520 by Ed Harris, when I was getting good results with AA2520 and cast in 308 Winchester.

I like both powders with jacketed in 243W and 308W................sub MOA groups in sporter barrels.
Last edited:


West Central AR
I was told a SEE could result . I've used it in a number of "full case , to slow to get hurt , drops pressure as fast as it builds it cartridges" without incident and used it at 1-3 gr under start loads with cast without issue also .
In a 257 Roberts I compiled data and ran a 100 gr Sierra 1 gr under avarage start loads for 100s .
In an 06' the group came at the minimum of 5 books start load which was 2 under the average and 1 below the next closest .
In 32 Rem I was -3.0 and reaching into max jacket velocities (of 32 WS) with PB cast good enough to hunt hogs with . Because it's so slow and so low pressure in 30+ cal I would think it would be pretty hard to get hurt . For what it's worth it's clean burn starts at 31,000 psi below that you get mummies to just plain old unburned powder at 35,000 and above it's clean although there's a little soot until someplace in the 38-40kpsi window and that's hard to hit with a 358 Win below 250 gr even with a full , compressed load .

I originally chose it because it was listed for 22-250 , 243 , 308 and 06' . It's supposed to be good in the mags up to 300 H&H also for jackets .
Until WWII it was the slowest powder available to handloaders but Hogdon had a little bit of 4831 left over from their 20mm contract after the war and that changed as in 74' they were still canning surplus for sale .


Well-Known Member
Thank you gentlemen.... oh,and you too RB(hearty harhar).

Now,I got 3 powders to try. And will.not be surprised if 4350 isn't "right there" on acc and velocity. Got more of it than the other powders..... and since getting away from JB's almost entirely,any chance to use it up is a good thing.


West Central AR
I didn't mention x39 with a 200 gr paper patched . Single feed over 25 gr about the neck out of 24" SKS for 1800 fps and mag length rattled around to get the powder up in the shoulder @ 22 gr for 1550ish . Both run 45,000ish with the one off spitzer .

Glad to help . I am running it under other cast and into jacketed territory generally with heavy for cartridge bullets . The 358 was just a fluke at 90% of bottom of the neck , 35-250 , 2100 fps .900 for 5 .

175s in a 12 twist 308 at I'm guessing 2300 fps . It was pretty aggressive on my end I expect it will be on the business end too .

I'm going to run it under the 312-230 NOE in a 9.5 twist 06' under the too slow to get hurt clause .

When I get back around to the 257 I'll run it with the NOE 260-120 looking for 23-2400 .

It'll run a 310-165 RD right through 2200 in a 30-30 325 Savage .