AR powder troubles

[J_McLeod]

I bought some H4198 and IMR 4320 recently and decided to try them in my AR. I know there are (and buy) better powders for the AR, but there's data for both powders in both .308 (lead for 4198) and .223 and that's what makes reloading fun. Anyways, I loaded the following to try to work up a good plinking load with my mid length AR.

Mixed brass, but segregated by type in different groups.
Wolf Small Rifle Primers
2.230"
55gr RMR pulled bullets. Unlike most of Jake's excellent products, you could tell these had been pulled. But he advertised them as such at the time, so that's no knock on him.

5 rounds of each, shot for a group at 50 yards from a bench with a red dot sight. The heaviest group in each was .5gr below Hodgdon's listed max.

H4198
19.2
19.7
20.1
20.6

None of the H4198 loads produced a decent group, possibly because none of them reliably cycled the action on my AR. 19.2 and 19.7 didn't even eject the case. 20.1 and 20.6 ejected the case, but wouldn't load a new one.

IMR 4320
23.5 Didn't cycle
24.6 Strangely, this load produced 2 double feeds in a row.
25.6 Produced a decent group, and 4/5 cycled.

63gr RMR FMJ Neither of these loads cycled my AR.
19 H4198
23.5 IMR 4320

I had heard that H4198 didn't always work in an AR, but I'm surprised that even the .5gr below max didn't work. With 4320 being right next to Varget and BL(C)-2 in burn rate, I thought it would do better. I know it wasn't the gun or magazine because both functioned flawlessly with some H335 and CFE 223 loads I'd brought. I think I'll try the IMR 4320 25.6 again, and maybe work up a bit more.

Anyone else try either of these powders in an AR? Would you go higher with the H4198 or just move on? Do you think these might work in my carbine length AR?

 

[TrickyDick]

so far i've only used H335 in my AR with relative decency. (300 yard match isn't the best place to test your loads) I was surprised to how well i did my first time with untested ammo, using crappy remington FMJ's. As far as 4320, it never crossed my mind to use in .223, i reserve it for my 7.62x54R. Perhaps it has something to do with case capacity in regard to it's burn rate. But I'm sure someone will chime in with more experience on the matter. I'm a beginner, only been reloading for a year and a half.

 

[thump_rrr]

You will get greater accuracy with a higher percentage of case fill.
I use 4198 in 7.62x39 25gr over a 123gr projectile. This is nearly 95%+ case fill.
4895 would be a better choice.
My personal .223 choice is IMR 8208 (XBR).

 

[phonejack]

You are not generating enough chamber pressure with those powders. Use 4895, varget, 748. Red dots are not for precision work

 

[BigBore45]

out of the powder shortage i have used H-380 in .223 Rem. with a 60 gr. bullet and it worked great. velocity not great but cycled the ar's fine.

 

[J_McLeod]

I also have 4895 (saving for .308), Varget, IMR 4064, 8208 XBR, H322, H335 and CFE 223. I think most of those are better for the AR, but I wanted to experiment and try new things. I like a red dot or irons on my ARs, so i'll shoot them that way and accept the groups I get. Not really going for high accuracy, though I might build another one for it.

 

[Rule3]

Based on the Hodgddon/IMR online data I would use the max loads for each powder and bullet weight using the data under the 55 gr Spr Sp and the 63 gr Sie sp.

Rather than trying to copy and past them here., they are on line. Hodgdon data tends to be a little conservative.

For their tests the 55 gr bullet they used exceed 3K fps. So it should function properly in your rifle. With 4320 and the 55gr it is a compressed load so that case is FULL!

 

[LiveLife]

I like H335 for .223.

I use H4198 for .300 BLK.

I like red dot sights for my carbines out to 75 yards. Beyond that, I prefer scopes.

 

[steve4102]

You are not generating enough chamber pressure with those powders. Use 4895, varget, 748. Red dots are not for precision work

Careful here, this statement is not entirely accurate.

Chamber pressure is not what cycles the action of an AR. Port Pressure is what cycles the action of an AR.

Port pressure is the amount of Gases that travel down the bore and enter the gas port.

The faster the powder the less gas and the less port pressure. Reduced port pressure should in No Way be equated to low "Chamber Pressure".

 

[phonejack]

You're right!

 

[243winxb]

55gr RMR pulled bullets. Unlike most of Jake's excellent products, you could tell these had been pulled.

The bullet choice tells me your not looking for accuracy.

Neither of these loads cycled my AR.

Try a different firearm. See Sierra data for a auto. http://accurateshooter.net/Downloads/sierra223ar.pdf Makes your loads look on the light side?

 

[BrianC636]

J_McLeod sent you a PM

 

[J_McLeod]

The bullet choice tells me your not looking for accuracy. Try a different firearm. See Sierra data for a auto. http://accurateshooter.net/Downloads/sierra223ar.pdf Makes your loads look on the light side?

Thanks. I'll print that out and add it to the loading book. I was using Hodgdon load data. Usually it works well.

 

[spitballer]

4198 never seemed to be satisfactory with 55's in my .223 bolt rifle, either. With 40 grainers it did better, but the charge was still so low (18 +/- grains) I could never be sure the flash hole was sufficiently covered by propellant after chambering. Finally gave it up in favor of a slower powder that filled the case better.

 

[horseman1]

Every make of firearm is different I guess. Looking back at my load data, I see I used H4198 with 55gr bullets and had no issues with cycling the action on my AR at the loads you listed. My OAL was within .005 of yours as well. I was using a Hornady fmjbt, and it was crimped.

I did find they were on the light side and have started using a bit slower powders for that combination. I'm saving the H4198 for use with some lighter bullets and see if they work out better there. I had a similar experience with IMR 4198.

The port pressure post above by Steve was very informative. Makes one wonder if any differences in the design of the gun would change the port pressure and timing, making that faster powder work OK in some guns, but not worth a hoot in others.

Who knows, I sure don't. Only been at this for a couple years.

H1

 

[J_McLeod]

Part of the reason I wanted to try it was for the low charge. 20gr vs/ 25gr for CFE 223/H335 means more rounds per lbs. I think I'll try it again a little higher with the Speer data and maybe in my Carbine, and then just save it for .30 Cal. (300 BLK and lead .308)