Forming 375 Ruger brass from 8x68s cases

That is a smoking load. How long is your barrel? I couldnt imagine running that high with n570 in my 30/375. Its different than rich's version but not by much.
 
Oldcappj7 (jace) 84.5gr n570. 3100 with a 225 is awesome.
Ya mine will do that as well. I ran it up as far as 3150 but backed off to 82 grains at 3050' for a hunting load. I have also ran the 225 at over 3100 with RL33.
I think it was 88-89 grains?
There IS a difference in case design performance!!
Mine is a 28" barrel.
 
I've pushed the 250gr at 3030 in my 338/375. 30" h4350
This is right in line with what I've seen. I get 2670 fps with 76.5gr of H4350 in an 18" barrel. Add an extra 12" of barrel and I'd end up right around 3000 fps.

Can this supporter get some #'s on
270 gr
ELD-X®
.757 (G1) ???
I haven't played much with anything over the 260gr weight range, but I'd expect 2850 fps on the low end from a 28" barrel with a 3.600" OAL. The case capacity starts to run out when you get into bullets much over 250gr so it's hard to get a slow enough powder in there really move the heavier bullets. I do shoot the 260gr Hammer Hunter at 2730 fps with a 3.610" OAL from my 18" barreled SP and that bullet is probably longer than the 270 ELD-X. I have a couple hundred of the 230gr ELD-X bullets on the way to test when I get time.
 
I've pushed the 250gr at 3030 in my 338/375. 30" h4350

RL16 is almost identical burn rate as H4350, but gives better speeds and is even more temp resistant.

In my 338-375 Ruger, I am getting 2980 fps with 76.5gr of RL16 behind the Berger 250gr EH in a 26" barrel. Can take it up to 77gr where I am just shy of 3000 fps, but get slight extractor marks so I backed it off.
My old load with H4350 gave me 2930 fps with 76gr (same bullet). 76.5gr and 2945 fps was max pressure with H4350.
 
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Using a powder similar to that phorwath used and the case lube I was able to keep a case of at least 2.580 consistently. So yes it seems good. I haven't shot that enough since to get a feel of numbers of loading but hit on 84.5 of N570 with the 225 ELDMs at approx 3100 depending on conditions. It is definitely stouter brass than the Hornady 375 Ruger brass.

Jace

Good to hear the fire forming success.

I used IMR SR7625 powder for the Cream of Wheat (COW) fire forming. I believe I was using 20 to 22 grains under the COW when fire forming the Norma and RWS 8x68S cases to elkaholic's 30/375 S.I. chamber.
 
I appreciate the OP bringing this forming to my attention. I have always used Hornady 375 Ruger brass for my 338-375R and its ok, but doesn't impress me when pushing pressure. I just ordered 200 Norma 8x68s cases from Midway. My bolt has the factory 700 extractor right now so it sounds like I will probably have to get a mini16 installed to work with the smaller rims. Thanks again for this info
 
That's a bargain on the Norma 8x68S brass. I just ordered some. Hope it's the same quality as the Norma brass I received from Huntington's.

For those willing to fire form and prep this brass for their chambers, the consistent case head strength compared to Hornady 375 Ruger brass will serve you well. Particularly if you enjoy wringing out maximum MV from your flame thrower. :)

If I didn't already own a 338 Lapua Rogue, I'd be tempted by the 338/375, or probably elkaholic's version of it in these Norma and RWS 8x68s parent cases.
 
Lengthening would be an option but I can shoot the 225's now at 3100' if I want to and the rifle shoots very well. I have enough mag to run longer coal but I'm at 3.7" now and most people would be limited.
Rich,
I'll be re-barreling soon. Is there any reason why your 30/375 S.I. Reamer couldn't be run 0.025" deeper, setting the shoulder length 0.025" longer?
AND then name it 30/375 S.H.I.?

H. for Horwath, of course! :D

Then run them with +50fps MV while utilizing the full length of the 8x68S casings.
 
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