What powder could it be??

[Whynot]

I am trying to duplicate some factory 300 win mag loads (that are quite expensive.) I have the factory brass- the same bullet- and primer. I'm not sure on the powder though. I talked to the company and figured they would tell me what powder they were using- as their main business is selling the bullets and not the loaded ammo. Unfortunately they wouldn't- so I am trying to figure it out. In talking to them I don't think that it is a powder made special for them- as they hinted it was a commercial powder.

I pulled a few bullets and weighed the charge.... In 300 win mag with a 185gr bullet it had a charge of 81.2 grains of spherical powder. It was all powder with no filler. According to my manuals the only powders that are spherical and can safely go that high are Ramshot Magnum and Accurate Mag Pro (that can both go to about 84grains). But my manuals are a few years old now, are there any other powders that I need to look into that match the criteria?

And yes- I know to work up to the 81.2- not just start there. Thanks.

[lonestardiver]

Many commercial manufacturers use a special blend that matches their specifications so it is likely not an off the shelf powder. Best way is to find a powder that produces similar velocities and pressure curve to match the load you want to match.

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[big honkin jeep]

Well if their main business is bullets then they probably also sell a load manual. Maybe a good place to start.
Nosler? If so they list most accurate powder tested as well as most accurate charge weight tested and I've found that data to be a very good place to start more than once.

[Evlshnngns]

I got nothin. Thats a lot of powder, according to my books.

[Whynot]

It is Berger, previously ABM. The ammo line started out small enough that I bet it is a over the shelf powder.

[big honkin jeep]

A little google and : http://www.bergerbullets.com/pdf/300-Winchester-Magnum.pdf
Though not a full reloading manual, looks like there's only one listed that fits your charge parameters

[Stumpkiller]

My mind went to Winchester spherical powders, but the data was WAY below the 80+ grains you show.

"Ramshot Magnum" is listed by Nosler (with a 190 gr, as they don't have a 185 gr bullet) and may be what you have, as it is a double-based spherical and might not blow you to kingdom come at that charge weight.

Go slow and start low.

[Whynot]

Thanks for the replies,- I was kind of leaning towards Ramshot Magnum as a starting point and it looks like it is the best option. It sounds weird to say it, but if I can get it to shoot as good as the factory ammo then I wont even bother with other load development. It is the best shooting factory ammo I've ever tried- at least in my gun.... but I have a hard time with that $50 per box.

Also- the brass is very light, I don't have my notes with me right now but I think it is about 40 grains less than my other brass... so that might be part of the reason it's not a hot load.

Thanks

[CFJunkie]

Berger Manual lists only one load for 300 Win Mag 185 grain bullets that has a max velocity of 81.2 grains Ramshot Magnum and it produces 3040 fps.
Berger uses QuickLOAD for their manual data and QuickLOAD is usually a bit conservative on PMax.
Also, since velocity sells factory ammo and the Ramshot Magnum has the fastest velocity, I wouldn't be surprised if Berger loaded that powder close to PMax for their factory ammo.

Probably worth a try.

[LHitchcox]

Most ammo manufacturers use non-canister powder, in other words the powder is blended to give the results the manufacturer set up. The best way to "duplicate" that load would be to chronograph it and then start with canister powders that are in the proper burn range. Work up slowly and see if you can reach factory velocity without excessive pressure.

[Dennis]

I tried the same thing several years ago. NOBODY will give up any info on Factory Ammo.

Best bet is go by a reloading manual, that's what I ended up doing, and produced a few "tac drivers" in the process.

[DogT]

My 1981 Nosler book shows a 180gr bullet and the only powder that uses that much powder is H-570 which I'm guessing is spherical but it shows MAX load at 84gr with a velocity of 2901.

I too am trying to come up with a factory comparable to the Hornady 55 V-Max at 3350 in 220S which is quite consistant and am not having any luck at all. I notice the Hornady cases are much heavier than any others I have too.