• This Forum is for adults 18 years of age or over. By continuing to use this Forum you are confirming that you are 18 or older. No content shall be viewed by any person under 18 in California.

What is the difference between IMR4350 and H4350

That's it. Was reading an article calling H4350 "gold" and Hodgdon was finally producing H4350 again. I can find IMR4350. Is H4350 better and why? Is it temperature stable and IMR4350 is not?

Thanks
 
H4350 is actually Australian-made and sold there as AR2209. It's the immediate slower brother of Varget (2208).

I've never used the IMR version but it's supposed to be faster burning and is not as temp-stable.
 
I've shot IMR4350 from 308 Win and 30 caliber magnums pushing out 200 grain bullets for 1000 yard matches in ambient temperatures at the low 20's to high 90's. Same load for each cartridge performed equally well.

I'm not convinced this powder - stability - temperature thing is all what it's cranked (assumed? imagined?) up to be.

MIL SPECS for 7.62 M118LR ammo temperature range and accuracy:

ACCURACY: Average horizontal and vertical standard deviation maximum:
Horizontal: 10.3 in. @ 1000 yds (about 30 inches or 3 MOA extreme spread)
Vertical: 14.0 in. @ 1000 yds (about 40 inches or 4 MOA extreme spread)
- or -
Horizontal: 1.3 in. @ 200 yds (about 4.2 inches or 2.1 MOA extreme spread)
Vertical: 1.5 in. @ 200 yds (about 4.5 inches or 2.25 MOA extreme spread)

Operating temperature Range: -65 F to 125 F
 
Last edited:
I've shot IMR4350 from 308 Win and 30 caliber magnums pushing out 200 grain bullets for 1000 yard matches in ambient temperatures at the low 20's to high 90's. Same load for each cartridge performed equally well.

I'm not convinced this powder - stability - temperature thing is all what it's cranked (assumed? imagined?) up to be.

Gonna check MIL SPECS for 7.62 M118LR ammo temperature range.
Hello Bart.. I have found over the years that some of the IMR Powders are pretty temp stable. IMR 4895, IMR 4831, IMR 7828 are the ones I know to be pretty temp stable. I am glad to see that IMR 4350 could also be placed on that list. Of course IMR 8208XBR is temp stable, however, it was designed to be that way, the others were not.
 
I have used quite a lot of IMR 4350 over the years in 243 win; 6mmAI; 270 win;
257 Wby; 30-06 and maybe more.
Always obtained very fine accuracy out of hunting rifles. I have never had problems with the temperature stability thing, if I'm going to shoot in warm weather than that is what temperature I work up the loads and zero the in rifle.... same for cold weather shooting. H4350 is reportedly more temperature insensitive and of course can also deliver fine accuracy.
Gary
 
To answer your question, Internet marketing Hype. Once someone convinces the masses something is "golden" or "gold", shooters flock to it like it's their last supper. IMR is Very close to H, but NOT interchangeable. Any prudent reloader will work up a load for THEIR rifle. Not use someone else's data found online. Opening a book or getting reloading info online, then not testing is not very wise.
 
That's it. Was reading an article calling H4350 "gold" and Hodgdon was finally producing H4350 again. I can find IMR4350. Is H4350 better and why? Is it temperature stable and IMR4350 is not?

Thanks
The best way to answer your question is to take out a couple different reloading manuals and review several loads. I asked the same question a few weeks ago. Review of loading data reveals that burn rates and charge loads can be significantly different from cartridge to cartridge.
 
when the only rifle I had was a Rem 700 BDL with a 26 inch Shillen 25-06 bbl I shot the 100 NBT year round,,in the summer I shot 52 grs IMR 4350 and in winter I shot 54 grs IMR4350,,in summer the 54 gr load would give heavy bolt lift and ejector swipe,,,in winter the 52 gr load wouldnt group as well and the 500 yard dope wasnt even close to what it was in the summer months,,

after 3 25-06 bbls I am considering a 6.5-06 or a 240 Weatherby bbl,,it doesnt look like anybody is ever gonna make a good long range bullet in .257 and I havent shot that rifle in 6-7 years,,
 
when the only rifle I had was a Rem 700 BDL with a 26 inch Shillen 25-06 bbl I shot the 100 NBT year round,,in the summer I shot 52 grs IMR 4350 and in winter I shot 54 grs IMR4350,,in summer the 54 gr load would give heavy bolt lift and ejector swipe,,,in winter the 52 gr load wouldnt group as well and the 500 yard dope wasnt even close to what it was in the summer months,,

after 3 25-06 bbls I am considering a 6.5-06 or a 240 Weatherby bbl,,it doesnt look like anybody is ever gonna make a good long range bullet in .257 and I havent shot that rifle in 6-7 years,,
BIB 110 Gr. BT. in a 9 twist barrel.
 
the last 6 BRDX bbl I had loved the 104 gr BT BIB bullets ,,what is the BC of the 110 BIB ?? I was thinking more on the lines of a 125-130 gr Hybird with a .625-.650 G1 BC
 
the last 6 BRDX bbl I had loved the 104 gr BT BIB bullets ,,what is the BC of the 110 BIB ?? I was thinking more on the lines of a 125-130 gr Hybird with a .625-.650 G1 BC
BC is .52

Good luck finding someone to make jackets.
 
BC is .52

Good luck finding someone to make jackets.
sorry to hijack this thread but there are lots of 105-110 6mm bullets that are better than that,,the 6.5-06 and 140 gr bullets is probably what I am gonna do with this rifle I have had since I was 10 in 1977,
 
That's it. Was reading an article calling H4350 "gold" and Hodgdon was finally producing H4350 again. I can find IMR4350. Is H4350 better and why? Is it temperature stable and IMR4350 is not?

Thanks
I have used a lot of imr-4350 but it is dirter then h-4350. I have a new 6.5x47 that is in love with h-4350 but hates imr-4350. and in the cold and very hot imr-4350 is very temp unstable.
 
H4350 was first....don't know why they called it that, but they did. Dupont made their IMR4350 as close to matching performance of H4350 that they could. Different? YES! AA4350 is another attempt at cloning. Again, different. All have similar burning rates, but are still different enough that you CANNOT exchange data between them.

H4227 was my favorite pistol powder. They discontinued it. My load was 18.5 grains and WLP primer. I now use IMR4227. My load is 19.5 grains and Wolf Mag Primer. Same gun, same brass, same bullet. Similar BUT DIFFERENT.

Be safe and work your way up.
 
H4350 was first....don't know why they called it that, but they did. Dupont made their IMR4350 as close to matching performance of H4350 that they could. Different? YES! AA4350 is another attempt at cloning. Again, different. All have similar burning rates, but are still different enough that you CANNOT exchange data between them.


I think not. Dupont introduced IMR-4350 'Magnum powder' in 1940 as a response to growing US interest in the .300 H&H Magnum cartridge. B E ('Bruce') Hodgdon wasn't in the powder business at that time (still being his former employer's star gas appliance salesman), so he couldn't have introduced H4350 before the IMR version.

Moreover, when Hodgdon started up his own business after the end of WW2, so 1945/46 at the earliest, all of his products were surplus military grades no longer needed after the cessation of hostilities and cancellation of government ammunition orders. It was only later after stocks of surplus product ran down that the Hodgdon Powder Co. got into the business of specifying and contracting out for new manufacture 'equivalents' to the older products, later still completely new grades such as H. VarGet. So, the first non-surplus H4350 would have been manufactured for Hodgdon in the late 1950s, more likely early 60s, by ICI Nobel Limited in Scotland, later still by its current maker ADI in Australia when ICI Nobel closed down. So, we are actually on H4350 Mark 3 now, or even 3a, having been over its lifetime:

Surplus
Scottish
Australian-1
Australian-2 (Extreme version)
 
I think not. Dupont introduced IMR-4350 'Magnum powder' in 1940 as a response to growing US interest in the .300 H&H Magnum cartridge. B E ('Bruce') Hodgdon wasn't in the powder business at that time (still being his former employer's star gas appliance salesman), so he couldn't have introduced H4350 before the IMR version.

Moreover, when Hodgdon started up his own business after the end of WW2, so 1945/46 at the earliest, all of his products were surplus military grades no longer needed after the cessation of hostilities and cancellation of government ammunition orders. It was only later after stocks of surplus product ran down that the Hodgdon Powder Co. got into the business of specifying and contracting out for new manufacture 'equivalents' to the older products, later still completely new grades such as H. VarGet. So, the first non-surplus H4350 would have been manufactured for Hodgdon in the late 1950s, more likely early 60s, by ICI Nobel Limited in Scotland, later still by its current maker ADI in Australia when ICI Nobel closed down. So, we are actually on H4350 Mark 3 now, or even 3a, having been over its lifetime:

Surplus
Scottish
Australian-1
Australian-2 (Extreme version)
+1;)
 
I am always late for the party,,,so,,,lets knock the pinyata out of the tree,,,from my insignificant little experience I have drew the conclusion that all powders burn faster when its hot and slower when it is cold,,,the stability factor is how good or bad the load velocity spread is,,,and even more important at any temp the powder burns more uniformly at high pressure rather than at low pressure/low velocity loads,,,Roger
 

Upgrades & Donations

This Forum's expenses are primarily paid by member contributions. You can upgrade your Forum membership in seconds. Gold and Silver members get unlimited FREE classifieds for one year. Gold members can upload custom avatars.


Click Upgrade Membership Button ABOVE to get Gold or Silver Status.

You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.


To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.

Forum statistics

Threads
164,714
Messages
2,182,956
Members
78,492
Latest member
Paulsen27
Back
Top