IMR or H-4227

[Mr_Flintstone]

When I first got started reloading, I bought some IMR 4227 for my M1 Carbine reloads. It works perfect for this using the data on Hodgdon (because they list the same loads for H-4227 and IMR-4227). I contacted Hodgdon when I started with the M1 Carbine, and they said that H4227 was no longer made, and I could use data from either powder, just start at the low end and work up. That made sense then. I have also heard that IMR-4227 is what used to be H-4227, and the old IMR-4227 is no longer made. I honestly have no idea.

My problem is that I have recently started using it for reloading .357 magnum, and Hodgdon doesn't have loads for all of the bullet styles/weights that I have. I can find most of them in the manuals I have, but there seems to be a wide range in load data between some H-4227 and IMR-4227 for same bullets. On some, the high end of one is less than the low end of the other. Some manuals only list one or the other, but not both.

In comparing modern (last couple years) IMR-4227, would it be closest to the old H-4227 or IMR-4227? Which load data would you consider safe for the new powder?

 

[ArchAngelCD]

First, I'm not a fan of 4227 in the .357 Magnum but it's great in the .44 Magnum.

I highly suggest you call or write Hodgdon and ask them these questions. Their answer will be better than all the opinions you are about to get.

 

[Mr_Flintstone]

First, I'm not a fan of 4227 in the .357 Magnum but it's great in the .44 Magnum.

I highly suggest you call or write Hodgdon and ask them these questions. Their answer will be better than all the opinions you are about to get.

I have contacted them. All I get is a canned response that says that I can use either data as long as I start at the low end and work up. I'd just like to know which "old" data is safe and which isn't.

 

[243winxb]

Check your can for place of manufacture.

Canada is IMR https://imrpowder.com/wp-content/uploads/2017/08/imrsinglesbase-canada8-15.pdf

Australia (ar2205) is H. Don't matter if the can has on it IMR 4227, its still H if manufactured in Australia. https://www.hodgdon.com/wp-content/uploads/2017/06/h4227-ar2205.pdf

But to be safe, use a starting load and work up as always.

 

[thomas15]

I have contacted them. All I get is a canned response that says that I can use either data as long as I start at the low end and work up. I'd just like to know which "old" data is safe and which isn't.

If you are determined to use IMR4227 or H4227 in 357 Magnum use the lowest published charge weight you have then work up from there.

 

[edwardware]

I second (third?) starting low, and suggesting a different powder fire 357 magnum. I have never been able to cleanly combust 4227 in a 357 revolver, and I observed rapid onset of very high pressure signs below book max.

 

[Swampman]

It may be a "canned response", but it's still good advice. Work up from minimum and pay attention to pressure signs.

I like H110/W296 for full power .30 Carbine, .44 Mag and .357 Mag loads.

If you want more sedate velocities, try Alliant 2400.

 

[Mr_Flintstone]

I guess I forgot to mention that these will be rifle rounds exclusively. I agree that 4227 is dirty in revolvers, but the loads I have made so far using the Hodgdon website data all burn clean in my lever action; especially the XTP loads. I'm just looking to branch out to some other bullet types. I have a lot of this powder, and I really like it in both my M1 Carbine and Henry Big Boy. I just wish there was a consistent source for load data, or they would go back to two separate powders with two different names.

 

[ArchAngelCD]

I have contacted them. All I get is a canned response that says that I can use either data as long as I start at the low end and work up. I'd just like to know which "old" data is safe and which isn't.

You already got your answer. Hodgdon said either data is safe. If there were any chance there was any danger they would not say that.

If you are intent on obsessing on the old data here it is according to Hodgdon.

The original IMR4227 has been discontinued. The original H4227 has been renamed IMR4227. In that case you should be using the old H4227 with the current 4227 but again, they were so similar it doesn't matter, as per Hodgdon. I'm not sure why the slight differences are concerning you since different sources most times publish different data for exactly the same powders.

 

[Iroquois]

I got the same response when I called. I wanted to try IMR4227 in the .41 mag but was confused by older loading data verses new loading data with IMR and H prefixes. I am currently using IMR 4227 and started with the “starting load” data in my loads. I have had no pressure signs using the IMR4227 in data showing H4227. Some of my manuals are 20+ years old and show different 4227 listings. Like everyone before me has stated, start slow, look for the pressure signs and you should be ok.

 

[bluetopper]

I didn't know you could cram enough 4227 in 357 or 44 Mag to be over pressure.

 

[243winxb]

two separate powders with two different names.

On the two 2017 msds i linked to in post #4 , you can see there are currently 2 different powders. 2 Different manufactures in 2 different countries. Same as the older powders.

IMR - Black granular solid.

H- Dark Gray tubules .


In the past around 2011? , H & IMR were both AR2205 from Australia. But not before or after.

 

[bluetopper]

No there are not currently two different 4227 manufacturers. Both those powders pictured are old. IMR hasn't put out powder in a metal can in a long time and H-4227 has been out of production for nearly as long.

 

[243winxb]

Both those powders pictured are old.

That photo is before AR2205 was sold as both IMR & H powders.

No there are not currently two different 4227 manufacturers.

Read the msds links in post #4

 

[bluetopper]

All I know is the current IMR-4227 is a dark ball powder.

 

[Airman Basic]

All I know is the current IMR-4227 is a dark ball powder.

I'd call mine a short stick powder.

 

[Jesse Heywood]

4227 bounced between IMR & Hodgdon a couple years back when the decision was made to make IMR powders rifle only. The ink was barely dry when the decision was over-ruled.

For revolver I have found my favorite 4227 loads is a slightly compressed charge. Doesn't seem to matter if it's for 357 or 45 Colt. And when case volume is the limiting factor, the load data source isn't that important.

 

[Jonesy814]

I actually contacted Hodgdon less than 2 weeks ago with the question of why I couldn't get 357 data for IMR-4227 from their online data base for 258gr bullets.They responded with beginning and max data for 110gr, 125gr. 140gr, 146gr, 158gr, 170gr and 180gr bullets
They also said IMR-4227 and H-4227 were so close in burn rate that they considered the data interchangeable and that H-4227 was no longer being made. Of course they also said start low and work up

 

[Varminterror]

What is the reason for doubting Hodgdon’s response, canned or not, stating all data for both remain safe, and also to follow good reloading practices to develop your loads?

Reading your post, I get the impression you’re stuck in a reloading mindset, and just need to pepper in some handloading moxie. Read the data, evaluate your bullets, determine a universally safe starting point, and load up. It’s ironic to me - many reloaders are reticent to step even slightly off of the map, but nobody really questions factory loads. Are they just a little too hot in your particular firearm? Or are they loaded too conservatively to be sure they are not? Start low, as normal, then start pouring more and more 4227 into the case. Your rifle and your rounds will tell you when it starts to hurt, if you listen.

Hodgdon is one company (Hornady is another) which is remarkably diligent about pressure testing all of their data. If they say it is safe within SAAMI compliant standards, then take that advice to the bank.

 

[Jack B.]

I sent an e-mail to Hodgdon in November of 2016 asking if load data for H4277 and IMR4227 is interchangeable.

Mike Daly from Hodgdon responded on the same day that they are the same powder and the data can be used interchangeably.