IMR4320 for 308, sure, why not.

[roggom]

Went on a powder run this week and hit 6 local shops and they were out of pretty much everything. One shop had just received a bunch of powder (no RE15 or Varget) but wanted $40 a lb(H4895), yeah fuck that.

Anyway I did find IMR4320 at two shops, so I picked up a total of 4 lbs (all the same lot, bonus).

Seems like this powder is the last kid to be picked for the team, so I did a quick search and it seems to have fallen to the wayside as most folks like the extreme powders of new. According to some burn charts it is similar to Varget in burn rate.

So i ran some numbers in quickload to match velocities of my current RE15 load. Went to the range and shot a very down and dirty OCW.

Was pleasantly surprised, Quickload did match the node pretty well, and the 1/2 grain variance was a little tighter than RE15.

Qualify: In my test all of the groups fell at the same POI, and the end result was the exact same load as my previous Varget load.

Conditions: Indoor range, 100Y, 71 degrees

Load: 44.5, 44.8(best), 45.0 IMR 4320, RP once fired from NOMAD, 168 SMK blems from Grafs, WLR, 2.830

Rifle: SPS-Tac 1:12 20" , Jewell, NF 2.5-10x32, McMilan HTG

Now, I do not have a chronograph, so I can not give actual velocity, I calc everything based on drop. Many folks do not prefer this powder as they state it temp sensitive. I am sure it is, but will take it out on the field and test. This weekend should get down to 32 in the morning, so I will try that. The warm weather will have to wait until summer.


Now as far as my 3 shot groups, its what I shoot for testing.


Summary,

I am pretty content with the results, I made up a pretty reasonable load using blem bullets, once fired brass and a bastard powder(only $23 a lb). Shoots as good/better than FGMM in my rifle. So for those who are low on powder, might want to give it a try.

Remember: Always cross reference a load with a published reloading manual before trying it in your rifle.


If you guys need a burn rate chart you can print one out from this thread, the Lapua/Vihtavuori chart is very easy to use


Thread link >>>>>>http://www.snipershide.com/shooting...184661-what-powder-should-i-switch-308-a.html<<<<<<<

 

[40xs]

Way ta go!! now you just made 4320 dissapear from the shelves! Just kidding. A friend and I were talking just 2 days ago about the same thing. He said 4320 was the "varget" of yester-year for Palma.

 

[FLIGHT762]

IMR 4320 is an overlooked powder with today's 308 Winchester shooters. IMR 4320 has short kernels and meters well. It's a great substitute powders when other, more popular powders are difficult to find. It's slightly slower than 4064 and has about the same charge weights as Varget.

 

[Southwind]

I tried a pound of it last year when I could not find any Varget or IMR 4895. I never did try it on .308, but I had good result with .223 w/ 69gr SMK and .243 w/ both 75gr and 87gr V MAX.

Someone posted in a different thread a while back that it shot best at near max loads, and I found that to be correct. Though I finished off the pound, I kept all my data for it incase it is the only powder on the shelves like it was a year ago. Although I prefer 4895, I would have no problems going back to 4320 in a pinch.

 

[buffybuster]

Been using IMR4320 for years in 308Win. Usually always available.

 

[HodgdonExtreme]

As popular as 223 and 308 are, there are more good powders for them than ANY other chambering.

A shame how many folks seem to think Varget is the only decent choice.

Good work and congrats!