I am not hurting yet but would like to have options available. I am not an experimenter so I searched for others that might have. I could not find where someone actually finished and how it turned out! I did run a PRC through a 375 ruger die with Imperial sizing wax and it necked up fine just a little short. Now to fire form. Will a CRF bolt hold the case tight enough to ignite the primer with no should to headspace on?

I haven't done any experimenting with this process. I saw a posting on Alaska Outdoor Forums, Alaska Handloading, where "gotboykins" posted "I've fire formed a couple of dozen 300 PRC for use in my 375 Ruger. No issues so far." Thread is about 1/2 way down the page, last post.

As I remember looking at the dimensions of the two cartridges they were the same length?? All my .375 Ruger brass needed to be trimmed after one medium loading. 5 pieces of new brass average 2.5744" long and the longest was 2.5780"

After sizing the shoulder appears to just a few thousands shorter. Starting the one I sized in the chamber the extractor will not pick it up. Hard to measure but side by side it is shorter. I will look at the Alaskan forum.

The .300 PRC shoulder is ~0.050" shorter than the .375 Ruger. I'd neck up to .416 and back down to .375 to set a false shoulder to keep the case tight against the bolt face.

if you really are looking for a solution try some 300 winm mag you will be surprise by the outcome.

quote:

Originally posted by medved:
if you really are looking for a solution try some 300 winm mag you will be surprise by the outcome.

yeah... case head separation on the second or third reload is a real surprise .. heck, if you do it right, it might just tint your specs, rather than take the whole eye...

NOT at medved, in the least --- these IDIOTS that make purposely dangerous brass that WILL have a violent casehead separation, but hide behind the internet .... well, i don't say such words in public

okay, let me back up --

the "less belt" diameter of an HH based case is .532 at the belt, .510 on the body. the ruger case is also .532, but that is at the rim, sloping to .315 at the shoulder .. we used to make 9,3x64 cases (and 376 styer) by turning off the belt of an hh case, and running it at .510 -- that works, there's no compromise or FOLDS in that approach. There is a cool enginerding term called stress riser -- it means just what is says, by construction as drawn, it will have a place where the stress is higher than the rest. a FOLD in a material is a normal and natural stress riser (SR for here on out), so... let's count the SRs, or folds, if one where DUMB enough to take a belts case and try to fireform, before even consideration of blowing it out so much.. okay, there's TWO there the belt folds both over and back, in a tight turn.. which means 3, like 4x SR - call it 3.5, and then it has to THIN and fold back here it meets the chamber wall ... which would be about 1.5 more, so 5x SR .. BUT it's 360 degrees in a NON-homogeneous metal construction .. oh AND its a high pressure round, call it 8k more than a classic HH load ...

so, after fireforming the WRONG brass, at least twice, to create a crisp seam and properly shaped case, you now have a round that, due to SR, material science, and pressure, WILL tear apart in 1 or 2 firings, you should wear both safety glasses and a blast shield ....


and some of ya'll thought high pressure loads in balloon head cases of the 45 colt was dangerous ....

Look, I'll take on risk, and eval odds... but sticking ones hand (eyes) in a garbage disposal and having a "friend" turn it on has about the same risk in my pov .. and, frankly, i'd MUCH rather lose a finger or two on my right hand (i terribly play guitar, so my left hand has higher value to me) than an eye, or two ... and while I am not handsome, i don't usually scares kids, dogs, or cause spontaneous abortions with my current looks, and i'd like to keep it that way

As suggested I checked out the Alaska forum. Says he fire formed 375 from 300 PRC but he did not say the steps he took. Until some one else say "this is how I did it" I'll wait until Hornady does a run. I do like my body parts!!!
Thanks Y'all!

As requested, there is a new thread on Alaska Outdoor Forums, Handloading, that details his steps and results.

As pointed out by jeffeosso, Moderator on this forum: be careful and check all advise!

Hopefully Hornady or someone else will get some .375 Ruger brass on the market.

quote:

Originally posted by LeonardC:


As pointed out by jeffeosso, Moderator on this forum: be careful and check all advise!
.

Just to be clear, I am a moderator, but I am not the moderator of this forum, that's Mark.

Loaded ammo is available.
It’s $100 a box but your time has value and it gives good brass

quote:

Originally posted by jeffeosso:

quote:

Originally posted by medved:
if you really are looking for a solution try some 300 winm mag you will be surprise by the outcome.

yeah... case head separation on the second or third reload is a real surprise .. heck, if you do it right, it might just tint your specs, rather than take the whole eye...

NOT at medved, in the least --- these IDIOTS that make purposely dangerous brass that WILL have a violent casehead separation, but hide behind the internet .... well, i don't say such words in public

sorry but it did work for me after 5 reloading on 20 different cases but i do agree it is not for everybody. anyway im not anymore the 375 ruger stayed with a 9,3x62 and not using 30-06 brass with it ...

I read the post on Alaskan forum. Either he left out some crucial parts or or just wrote it. Once the hot gas from the primer hit critical flow through the flash hole, with no shoulder to head space on, the pressure in the prime would push the case forward to the chamber shoulder. With no wading between the powder and the COW, all the energy from that small amount of powder would be lost in/on the COW. Charred cream of wheat! I knew it would not work but I had the case I had already necked up. Plug of gulf was in the neck instead of TP. NOT!

I necked up some ( ADG ) 300PRC brass to 375 Ruger,fire formed it with a light load with cast bullets
and it turned out all good
I necked up gently...5 or 6 steps I think it was
8mm,.32 ,338,35, 9mm,9.3,.375....with theneck well lubed
ADG Peterson brass isof far better quality then Hornady