Range Report – IMR 4227 behind 55g SPBT in my Oly AR 15.

I found the recipe for IMR 4227 on the Hodgdon’s website back in December. None on my manuals have 4227 in their tables. I looked online again today and it is gone. I think I know why, read on.

Back in December, Hodgdon’s recipe started with 16.0 g and ended with 17.0 g.

I really like the ease of metering IMR 4227. Much, much easier than IMR 4198 or 4064 – that’s one of the reasons for me trying IMR 4227.

I also liked the idea if using less powder. Figured it would make my pound of powder go farther.

So, I reloaded five recipes for IMR 4227 and none of them were satisfactory to me. All would make the Oly AR 15 eject the spent case, but most of the reloads would not drive the bolt back far enough to pick up the next round. I had to cycle the bolt by hand, using the charging handle.

Here’s the range report: I fired 10 rounds of each.

14.7 g of IMR 4227
Highest fps – 2402
Lowest fps – 2184
Average – 2329.86 (+/- 72.12 fps)
All ejected, bolt never went back far enough to pick up the next round.

15.0 g of IMR 4227
Highest fps – 2381
Lowest fps – 2252
Average – 2332.74 (+/- 48.25 fps)
All ejected, bolt never went back far enough to pick up the next round.

15.3 g of IMR 4227
Highest fps – 2495
Lowest fps – 2262
Average – 2372.44 (+/- 122.56 fps)
All ejected, bolt never went back far enough to pick up the next round.

15.7 g of IMR 4227
Highest fps – 2530
Lowest fps – 2331
Average – 2397.00 (+/- 133.00 fps)
All ejected, the bolt went back far enough to pick up the next round 2 times.

16.0 g of IMR 4227
Highest fps – 2560
Lowest fps – 2408
Average – 2501.00 (+/- 59.00 fps)
All ejected, the bolt went back far enough to pick up the next round 5 times.

I’m going to reload 16.5g and 17.0g to see if they will chamber the next round.

Do any of you guys have any experience with IMR 4227?

PS

While I was at it, I chronied 10 Remington Factory 55g loads, here’s the results
Highest fps – 2867
Lowest fps – 2724
Average – 2801.4 (+/-65.60 fps)
AR functioned flawlessly.

Later, I chronied 10 more of my 55g reloads, they were a recipe from my reloading manuals, 24.8 g of IMR 4064:
Highest fps – 2739
Lowest fps – 2597
Average – 2674.93 (+/-64.07 fps)
AR functioned flawlessly.

Hack

I have used both IMR and H 4227s in the 223...

it is a great powder at the reload bench, very user friendly for 22 caliber necks...

I found IMR's version was much more accurate than Hodgdons...

I also found that IMR 4227 was also much more accurate than Alliant 2400 powder, which has pretty much the same physical make up... small grained and user friendly on 22 caliber necks..

None produce enough recoil to cycle most Semi Auto actions, on ARs or Mini 14s......

In a bolt action, I have found more accurate results using other powders...still within the focus of using less powder.. the best two being SR 4759 and Blue Dot ( of which I have been flamed by a few on here for using, since the factory doesn't publish data on it...)

Yes, I have done it too, in my mini-14.
I too could not get the action to pick up a fresh round although my measured velocities were very close to my normal loads at 3100fps (I no longer have the records)
Accuracy in the mini-14 at those levels was not worth contemplating but I did load up some 'hornet equivalent' loads that shot great! Those would move the action back a little but not enough to eject the case. The powder was an equivalent to Unique. The H4227 equivalent loads I used were somewhat less versatile and I felt put me too close to the edge as far as an inadvertant overload was concerned. (I take the view that if one has a need for reduced loads of this nature it might be a good idea to keep those loads to a level at which a double charge is still safe. That's not a dig at seafire2. He knows by know that I hold him in high esteem! It's just been my philosophy all along, that's all).

Cheers seafire2.

No worries 303...


I don't mind different opinions..

I do mind being told I am doing this stuff to kill someone or someone's death is going to be because of me...

of course arguing on the internet is kind of akin to the special olympics...

But since Hot Core knows all about pressures, and states these loads are overpressured, or can have pressure spikes, why hasn't he given us all numbers to back up his accusations?

There is a big difference in making an accusation or backing it up with proof...

but until he backs it up, he is just blowing wind...

FWIW, the old DuPont manual listed a max of 17.5 IMR 4227 with a 45 grain bullet, for 3000-ish fps.

They don't list the powder with any bullets heavier than 45 grains. I've used it in .17 Rem and .223 long ago and it worked OK. No better than my Blue Dot loads but it'd take me a while to dig up my load notes ..

Like any other reduced loads, I made very sure to keep them "reduced"! High pressure loadings with these quick powders is a lousy idea but they work really well if throttled back.

Mark

quote:

Originally posted by seafire2:
I don't mind different opinions.. I do mind being told I am doing this stuff to kill someone or someone's death is going to be because of me...of course arguing on the internet is kind of akin to the special olympics...

But since Hot Core knows all about pressures, and states these loads are overpressured, or can have pressure spikes, why hasn't he given us all numbers to back up his accusations?

There is a big difference in making an accusation or backing it up with proof...

but until he backs it up, he is just blowing wind...

I'm not putting a dog into this fight but it would seem to me that with all the criticism Hot Core has dished out to me and a couple others who use Oehlers M43 to measure pressure, including Dr. Oehler himself, I would think he should have a better method of measuring pressure than what he uses. Additionally Hot Core's uses continual rants against those of us who mention how chronographs may be used to monitor pressure. He continually points out that such devices are not precise and give no indication of pressures. Now in these threads regarding the use of Blue Dot he uses these very methods as his "proof". A bit of hypocracy on his part don't you think?

BTW; I have also used 4227 in .223s (bolt guns) to develop good and very useful .22 Hornet level loads. However I've not used any Blue Dot for such loads which is why I'm not putting a dog in this fight. I am only noting as a bystander the hypocracy and contradictions that Hot Core continually uses.

Larry Gibson