Lantrad and I are preparing to compare some .307 Winchester data. I will use my Winchester M-94BB and Lantrad his converted Marlin 336.
Lantrad wants to start with AA 2520 and while I do not normally agree to work with an unknown rifle and Ball powders the opportunity to compare the two rifles together is too rare to pass up. I bought some AA 2520.
While looking at my previous data I decided to fill in a few holes at the same time. I use IMR 4320 as the powder of choice in my .25-35 and .25-35AI rifles. I have used IMR 4320 in my .307 but up till now I have not taken a serious look at it.
Reviewing Ken Waters Pet Loads articles on the .307 Winchester and .300 Savage indicates he developed both high velocity and good accuracy in both cartridges with 4320. Waters commented IMR 4320 seemed to develop higher pressure in comparison to IMR 4064. Waters did not include IMR 4320 in his .300 Savage Pet Loads Update article. IMR 4320 can be a difficult powder to get an accurate handle on so I have been reviewing old load data for the .300 Savage. IMR 4320 appears to have been a very good all-around powder choice for the .330 Savage. Across all bullet weights from 110 to 200 grains, IMR 4320 appears to generally develop the highest velocity or comes in a close second. Significant comments on accuracy are harder to pin down but I have not located any negative comments. My old Pacific reloading manual lists some excellent accuracy results from IMR 4320 in .30-06 Match rifles.

I thought I would ask the .300 Savage shooters on the board if you have any experience with IMR 4320. In particular I am interested in any comments on hot weather and visual pressure indications and accuracy results with all bullet weights.

I tend to use a lot of the Reloader products 15 especially. I have used H380, but am not a big fan of ball powders. I get great accuracy from the RE15 from my 303 Sav, my 250 and my 300. Les

William,

I think 4320 would be the one just about right for the 300 Savage, with 165s and 180s, and tied for first with 3031 with 150s. I also do the Re15 thing, like it fine with the 308 Win, but I am not sure that I have tried it in the 300 Sav. I feel the same way that you do about ball powders in this cartridge, but look forward to hearing your results.

My 300 evidently has a pretty loose chamber, and it seems like I really work the brass for re-loading. Primers always seem flat to me, even if I'm not shooting max loads, and regardless of the time of year.

Accuracy is just average, and I did have my share of difficulty finding loads that would optimize its performance. The gun was in a kind of semi-retirement until recently, when my daughter wanted to go to the range with Old Dad, and I picked it out because I knew it wouldn't kick her to pieces. She is doing really well with it, and went through my reserve of old loads, so I am back to the bench with this gun. 150s only, and a 90% load from Sierra, of IMR 4320. I am not sure of the grainage, but I do think that it is the recommended "accuracy" load in my Sierra manual, 40.3? something like that. It is doing pretty well, and I haven't noticed anything to be concerned with.

At any rate, this is the powder that I would recommend, and I hope that it serves you well.

Best.

Steve

I have tried almost every powder of the "medium burn rate" in the .307. Alliant Reloder 15 is the velcity champion with Hodgdon Varget right behind it. Varget will give just a little better accuracy across the board.

I only want to play with IMR 4320 to round out my data base. I like IMR 4064 in the .307 for less than maximum hunting loads. I have killed quite a number of deer with 40.0 grains of 4064 and 170 grain bullets - this load giving about 2350 fps in the 20" barrel.

The similarities between the .307 and the .300 Savage amaze me. The cratridges are very similar in their performance possibilities.

Yes, a close look at the .308 Win. will bear many similarities to the .300 Savage, the .307W is merely a rimmed version. Strange how the .300 Savage is near obsolete while the .308W is extremely popular.

Shows how ex-military cartridges sway the opinions of shooters.

The limitation for the .307 is the short, 2.55" oal. This limits case capacity. Alliant RL 15, Hodgdons 335 4895SC and Varget all help to overcome this limitation. The short oal is the reason I do not favor bullets heavier than 170 grains in the .307.

307 is nothing but a 308 with a 30-30 rim on it, i use 307 to make 303 Savage Brass. But Ballistically i am with you William, they 307 has to be loaded down, so it is about the same as having a 300 Sav, which I swear by. Guess I really need to try out some Varget, how well does it work in temperature extremes. Les

I really need to try out some Varget, how well does it work in temperature extremes. Les

Both of Hodgdons mid range powders - 4895SC and Varget really shine in the high heat we are going through now. Cartridges that are hot to the touch will not exhibit signs of high pressure. I have compared Hodgdons BLc2 and Winchester 748 at the same temperatures and experienced a lever kick with published maximum loads. I like 4895SC and Varget for both hot and cold weather shooting. I have only tried these powders down to 10 deg. above zero - about as cold as it gets here.
Hodgdon 335 is very similar to 4895SC and if you prefer a ball powder that is where I would start. I have never experienced anything "unexpected" from 335 in hot or cold weather.

Thanks, will give the Varget a try. Guess I will have to start with 30-30 loads for my 303, can't find any data on Varget for that, I do have data on regular 4895, is it interchangable with 4895SC? Thanks, Les

I do have data on regular 4895, is it interchangable with 4895SC? Thanks, Les

I have found my data for H4895 and H4895SC to be interchangeable in the .307.

Appreciate it. Les