I have been reloading for a short period of time and have been using IMR4350 for .308, 25-06, .270 and 30-06. How do you determine which powder is best for the caliber you are shooting?

I assume you have or are acquiring several (or more) reloading manuals. An alternative is to visit several on-line reloading data sites.

Looking in several of them, take note of which powder(s) produce the highest velocities with the bullet weights you want to use, in the "caliber" you are loading. Those are probably the powders best suited to the weight of bullet you use in the size case you are shooting.


That DOES NOT mean you need to try for that velocity, or even ever should. It simply means that powder is well suited to that cartridge, releasing enough energy to perform at maximum velocity without creating excessive pressures.

The 4350 you mention is a pretty good choice in the .270, the '06, and similar size cases with similar expansion ratios. It is probably a bit too slow burning for optimal performance from the .308 Win unless you are shooting 200 gr. bullets. For the .308 something more along the line of a "medium" burn rate powder, such as 4895, 4064, Varget, AA 2520, etc., would likely work a bit better.

I have a Nosler and Hodgdon handbook. Most of what I have been going by was in the Nosler book because I have been using their bullets. When I first started reloading a friend gave me some of the IMR4350 and I never tried anything else. In the 308, which is what I have been shooting more than the other, I am shooting the 150 grain Supreme Ballistic Silvertip bullets. I will try one of the other powders you listed. Any preference or are those all close as far performance to each other.

Thanks

The 308 is a round that is inherantly accurate and will shoot quite well with a large number of medium burning powders such as Varget, RL-15, N-150, WW-748, and several others. I've personally had great results with 46.0grs of Varget and 165-168gr bullets. I would try them next in the order I wrote.
I don't think you can really claim a "best" powder for the 308 since so many work so well.........................DJ

quote:

Originally posted by Alberta Canuck:
Looking in several of them, take note of which powder(s) produce the highest velocities with the bullet weights you want to use, in the "caliber" you are loading. Those are probably the powders best suited to the weight of bullet you use in the size case you are shooting.

Good advice here.....and may I add that the Hodgdon website indicates a compressed charge by placing a "C" by the load......and I'd personally prefer a hi-velocity with a slightly compressed load and pressure somewhat under 60 KPSI or under 50,000 CUP

There are several excellent powders for the .308 Winchester

Hi Robe;I'm new to reloading myself.1st was for my 338WinMag last year and now this summer my 308.Varget(less sensitive to temperature extremes as in shooting in winter"36degrees" and summer"86degrees".There can be a change in pressure,and R15(very clean burning) have performed very well with 155&168gr bullets.IMR4320 is a good versatile powder and has shown very consistant velocities.A tool to help asses load performance is a chronograph.You can tell by the information what the most efficient load is of what your working with.As an example.Load#1-155gr Nosler Ballistic Tips with (45 grains) of R-15 give an Avg Vel of 2500 feet per second.Load#2-(xxxx with (45.5) grains of R-15 gives an Avg Vel of 2525 fps.An increase of only 25 fps.Not much of an increase in fps for the amount of increased charge weight is it?Think of it as a sort of; return for amount invested.Anyhow;you can't go wrong with Varget and R-15.R-15 works very well with 30-06 too.

As suggest by one of my many reloading manuals; choose a powder in the middle of the burning rates for which bullet weight you have choosen. Normally, the IMR 4350 choice would be considered too slow for the .308. Those powders which produce the highest velocity for a given cartridge bullet combination often will produce the best accuracy as well.

Shootin a 308 Win ?
Get some Varget...RE15..H4895..BLC2...

The most accurate powder for the 308 is Vithavouri 140.Varget is a very close second.Use 140 if you MUST have a one hole 200yd 5 shot group.Most accurate load is 41gr for the 168gr and 42 gr for the 155.

the .308 is very easy to load for, stick with powders with about 90 to 95% density with the bullet you choose to shoot, that gives you the highest velocitie. 4064, varget, 4895, RL-15 all are great for this round... i personal like 45.0 grs. of RL-15 with 150 B.T.s i find this the best for my .308,.. evry accurate

Thanks guys for the info. I will try some of the powders listed. It appears there are several that are repeat favorites by several posted replies

I've had great luck with Benchmark, with 4320 and RL15 close behind. This is with 165 & 168gr bullets. I don't hear much about Benchmark and haven't had a chance to run it thru a chono yet but you will see tiny groups on paper.