Making 300wm brass from 300hh?

sikwhiskey

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Finding it difficult to find any win 300wm brass, I do have about 80 ww300h&h brass collecting dust since the 80's or so. Still new in box with a price tag of $3.99 for 20.
Wondering how to make 300wm brass out of them? I do have some pistol powders on hand, plenty of toilet paper to fill the case along with plenty of hard cast, gas checked/lubed boolits, 180grn. Kind of wondering where to start? Trim first then full size? Anneal? Then powder load? I have hs6, tite group, 700x, red dot, blue dot. Also have powders from blc2 through imr 7828 for burn rate.
Looking for someone with experience for advise.
 
What brand of .300 H+H ? I can either buy them or I may have some .300 Win mag laying around............Harold
 
Same deal as Harold! I'm sure I have 300 Win brass lying around. Hell, I'll give you an even $20 for all the brass. Tidy profit!
 
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Wininchster WW super. Not sure if I want to swap them for new production once fired brass, thinking Fire form them, reload then go hunting....

It's not that simple. Stand a case next to a 300 WM case. Not quite the same...at all.

I might have new brass. But it's a foolish waste to screw that stuff up so that you can have new brass without the fuss.
 
BUM, I'm aware of how different the cases are, I'm also aware the Roy Weatherby designed his 300 off the 300h&h case, He and many others after him would chamber their factory 300h&h ammo into their newly designed 300wby rifle and end up with fire formed 300wby brass, that was how they made brass for the 300wby.
Aside from case length, shoulder and longer neck the win mag isn't so different than the wby.
I'm more interested in the process of fire forming than selling the brass, I may only form 5-10 and see how the brass turns out and how many full load firings I can get out of it before the necks crack or primer pockets loosen, if the old brass is no better than new production win brass I will more than likey trade or give away the rest of the HH brass.
 
I have never made 300 Win Mag from 300 H&H, but I had 10 R-P 1F 300 H&H cases that I made into 308 Norma Mag.

The process is easy: Run your 300 H&H into your 300 Win Mag FL die. Remove, trim to length [2.610"] and chamfer inside and out.

Run it through your FL die once more, just to be sure. Load with a regular hunting load, shoot in your 300 Win Mag rifle.

Voila!! a perfectly formed case, now a 300 Win Mag instead of a 300 H&H.

I never lost even one of the 10 cases that I made into 308 Norma Mag, and, in fact, am still using them.

Regards, Dave.
 
I have never made 300 Win Mag from 300 H&H, but I had 10 R-P 1F 300 H&H cases that I made into 308 Norma Mag.

The process is easy: Run your 300 H&H into your 300 Win Mag FL die. Remove, trim to length [2.610"] and chamfer inside and out.

Run it through your FL die once more, just to be sure. Load with a regular hunting load, shoot in your 300 Win Mag rifle.

Voila!! a perfectly formed case, now a 300 Win Mag instead of a 300 H&H.

I never lost even one of the 10 cases that I made into 308 Norma Mag, and, in fact, am still using them.

Regards, Dave.

Thanks Dave, thats what I had in mind. ill give it a try. Should I anneal before sizing and fire forming or after? I'm thinking before? as it is new brass I'm not sure it will matter? Thank you for the info!
 
If you are set on it then just follow what Dave says..........I have made many, many cases from other cases including 375 Ruger from 300 WM W-W brass, which involves blowing out the entire length of the case. Just fired loaded 300 WM in the 375 and as Dave says "Voila" 375 Ruger brass. I fire 30-40 Krag in my 35 Win to make brass for it, I have fired lots of 308 in my son's 358 to make brass for it and I once made a couple 350 RM from 375 H&H cause I was 2 short of an even 100.
264 WM to 257 Wby
7mm RM to 7MM Wby
300 H&H to 300 Wby
375 H&H to 340 Wby
375 H&H to 375 Wby
308 to 243, 260 Rem, 7-08 and 358
30-06 to 7X57 and 8X57 and 9.3X62
and on, and on, and on..................................


You may need to turn necks as you are into the shoulder going from the H&H case to the WM case, and you may experience thick necks.
 
If you are set on it then just follow what Dave says..........I have made many, many cases from other cases including 375 Ruger from 300 WM W-W brass, which involves blowing out the entire length of the case. Just fired loaded 300 WM in the 375 and as Dave says "Voila" 375 Ruger brass. I fire 30-40 Krag in my 35 Win to make brass for it, I have fired lots of 308 in my son's 358 to make brass for it and I once made a couple 350 RM from 375 H&H cause I was 2 short of an even 100.
264 WM to 257 Wby
7mm RM to 7MM Wby
300 H&H to 300 Wby
375 H&H to 340 Wby
375 H&H to 375 Wby
308 to 243, 260 Rem, 7-08 and 358
30-06 to 7X57 and 8X57 and 9.3X62
and on, and on, and on..................................


You may need to turn necks as you are into the shoulder going from the H&H case to the WM case, and you may experience thick necks.
I will be sure to turn/measure the necks after fire forming, not a problem. Thanks C-fbmi, I enjoyed reading your posts on making/fire forming brass for the "new king" lol. My father used 300hh and 375hh to make 358 and 375 Mashburn, Sadly I was too young and dumb to pay attention to the process. The custom rifles chambered so were given/sold to friends in the yukon and Alaska, for things that go bump in the night.
Some say the internet is useless, sites like this renew my faith in humanity.
 
Aside from case length, shoulder and longer neck the win mag isn't so different than the wby.



It would have been easier to say "because of the identical case head" rather than enumerating the numerous reason the case is different.

I have some 300 Winchester magnum brass for sale.
They are Federals and Imperials.
$0.45 cents each or $0.40 cents each if you take them all.
All are once fired and very clean.
I'm on Ontario
PM me

He seems bound and determined to go through with this wasteful experience of resizing, trimming and fireforming the more valuable H&H brass for the ultra-rare and impossible to source 300 WM. It actually boggles the mind.
 
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