Any experience with IMR4227?
 

Good, bad or indifferent...I'd like to hear about setups with IMR4227 in AR platforms. I was able to get ahold of a pound and figured I'd give it a try. The burnrate shows almost the same as VihtN120 and the numbers are fairly impressive when a mock-up is done in QuickLoad.

I don't plan to use it for anything < 168 and will probably stick to SMK's up to the 240's.

Thanks in advance!

IMR4227 is a moderately fast double base stick powder. It's commonly used for the 223 Rem with light (40 grain) bullets though some more modern powders give higher velocities at the same peak pressures.

Quickload shows me that 9.8 of IMR4227 in a 300/221 would drive a 240 gn SMK at 1010 fps assuming an unlubricated bullet and normal barrel friction with an 85.9% case fill and 2367 psi muzzle pressure. It seems to me that could be a reasonable and stable load for use in a AR-15 for use with a suppressor. The peak pressure however is only 30kpsi so it will probably leave residue. Personally I'd choose a little faster burning but bulkier powder for heavy bullets in my 300/221s. Lighter bullets need even faster powder.

For a 10" 30 Carbine T/C pistol a good subsonic load using a 240 grain SMK seated at 2.28" OAL over 9.1 grains of IMR4227 is a 100% case fill, 1020 fps. 38kpsi peak, 3.7kpsi muzzle.

It's stable with the 10" twist barrel because where I shoot at over a mile elevation.

I haven't ever tried 4227 in .300 Whisper. However, it is my least favorite powder that I've used in magnum revolver cartridges.

It is a stick powder, so it doesn't meter all that well.

Even with full-power loads, I would always get a lot of unburned and partially burned granules thrown all over the place. I mean a lot! Shooting with these loads felt like having someone throw a handful of sand on my arms and head. The inside of the gun looked like it had been dragged across the beach too.

I'm thinking there are probably better choices.

My results so far
 

SSK AR-15 upper
16.25" 1:8 twist

220 Sierra MK
9.2 grn IMR 4227
Rem 7 1/2 primer
OAL 2.222"
221 FB case capacity 24.2 grn H2O
1-800 fps
2-876
3-893
4-824
5-865
ES 93
SD 36


220 SMK
9.7 IMR 4227
Rem 7 1/2
221 FB case
OAL 2.224"
1-903
2-936
3-883
4-935
5-890
ES 53
SD24
Case Capacity 24.2 grains H2O

220 SMK
9.7 IMR 4227
Rem 7 1/2
OAL 2.224"
1-938
2-936
3-890
4-961
5-903
ES 74
SD 30
Case capacity 23.2 grn H20/reformed 223 Headstamp CJ8

220 SMK
10.2 grn IMR 4227
Rem 7 1/2
221 FB case cap 24.2 grn H2O
OAL 2.110"
1-1098
2-1098
3-1107
4-1090
5-1088
ES 19
SD 07

None of these grouped especially well. I'm going to weight sort my cases.
The last loads I shot with AA1680 I noticed vertical stringing and I think it was caused by variations in case capacity.

We've been shooting 4227 in the 300 and the 510 for a while and it seems to work just fine. I've not seen any problems with unburnt powder in either round and velocity has been pretty consistant. We haven't done any benchrest type accuracy testing though so I can't say anything other than it seems good enough to nail the target. I don't shoot AR's either so no idea what it will do out of them. It works fine in the SIG 552-300 though with a 9 inch barrel.

Frank

4227 powder for 300 whisper
 

I sent you a pm about sending some data in an excel spreadsheet. Bottom line is that it worked for me and did ok. I will continue to work up some more loads for it, but I think there are better, more reliable powders

I have been using 4227 :
18.0 gr IMR 4227
LC brass
Lapua 100gr HPCE
shoots very well from My 16" AR as super sonic load

My favorite subload for my Ar (1x10 twist barrel) is:
10.5 gr 4227
CCI 400
LC brass
Hornady 190gr spbt
COAl 2.240"

Hope this helps.

Sorry...it's been awhile since I've had time to post a follow up on this topic.

16.0gn IMR4227
147gn Hornady FMJ w/ cann
2.10" COL
~1750 fps

Nets a full case and ~95% burn rate according to QuickLoad.

Cycled both pistol and carbine gas port systems w/o feeling excessively harsh and fed reliably...as long as reasonable time was taken between shots (not good for double taps).

Accuracy was decent and this has become my de'facto load for forming first fires of 300WTF brass.