I posted a similar question at the tail end of another topic, which probably wasn't most appropriate, and so will repost here.

I read the tech tip on performing the Topic procedure but was wondering if anyone could supply powder and charge weight information?  Also, does this result in shorter cases than could be attained by using 38-55 brass?

Yes, the brass will be shorter than .38-55, but perfect for the .375 Winchester!

Use 5.0g Red dot, fill the case with cornmeal, then cork the neck of the case with paraffin wax, shoot, and you have a very cylindrical case perfect for the .375 Winchester!

Hope this helps!

God Bless,

Marshall

Thanks Marshall,

Have any idea what the appropriate charge of Bullseye would be?  I don't have any RedDot in my locker right now.  Otherwise I guess I'll have some!

Bart,

To fireform those cases use 4.0g Bulleye in the case topped off with either cornmeal or Creame Of Wheat to the middle of the neck on the .30-30 case, then plug with the parrafine wax.   No, it doesn't have to be Red Dot, it's just my powder of choice for this and other such applications.

Let us know how your fire-forming comes out!

God Bless,

Marshall

I loaded up 20 each of Win and Rem 30-30 cases as prescribed.  I wasn't sure if you meant to seal the tops with melted paraffin or just plug them.  I put the bar of wax in hot water for a bit and then just stuck the necks of the cases in and broke off a plug.  It appears that the main reason for the wax is to hold the cornmeal and powder in place anyway since I don't think it could provide much resistance, melted or not.  I ended up with about a 50% yield rate.  Some cases are almost perfect, while others hardly expanded at all.  Given my technique, I believe that a slightly higher charge of Bullseye would have worked more reliably.  Since I'm off today I'm going to repeat the experiment and use something more like 4.1 - 4.2 grains of powder.  I'll let you know that result.

I'm interested in seeing what the difference in capacity will be between the two different makes of cases.  At first I'd have believed the Winchesters would have had the most capacity but based on empty 30-30 case weight it appears that they are the heaviest.  There are other factors though that I couldn't account for such as length since my calipers are in storage.

This is a good thing to know how to do.  375 Win cases are getting harder to find (and more expensive) while 30-30 cases may be the most common centerfire brass encountered.  If times get hard this will make one a little more self sufficient.

An update on the fireforming experiment:  A little more Bullseye did the trick and I now have 40 perfect 375 Win cases with 30-30 headstamps.  The difference between Win and Rem cases was in the noise regarding case capacity.  What I did find though was that the fireformed cases held 3% more water (by weight) than the factory 375s and 38-55s held 6.5% more water than factory cases.  Now I'm not quite being fair since the factory 375 cases were trimmed to min length when they were new and the others have had none, but I doubt it would make much difference anyway since those factory cases required almost no trimming to reach minimum length.  So I guess if you're looking for maximum case capacity the choice is obvious.  But for everyday use these "30-30 turned 375" cases are the ticket, especially if you get satisfaction from making things yourself.

BTW, these new cases, loaded with CCI 200 primers, 33.7 gr RE7, and BTB 250 LFNGC's kept an aerosol can jumping on the hillside from my Marlin at about 50 yds.  I'll be more scientific with velocity and accuracy when my chrony gets unpacked from storage.  I was pleasantly surprised to find zero visually detectable leading in the unlapped microgroove barrel too.

This is a "must try" for any serious 375 Winchester handloader.

Since JackR brought this up, I should update the posting.

The last time I fireformed cases I used 5.0 gr of Bullseye and sealed the neck with a 1/2" square polyester wad, tamped into place with a chopstick.  Of 60 cases only one failed to form, while 3 split.  I believe this is the recipe for Bullseye.  The difference between using paraffin or poly wad wasn't apparent, and probably has no effect.  The biggest difference is that working with poly is much easier than soft paraffin.  I don' t know if backing off the charge a tad would have prevented the splits or not but I doubt it.  Losing 3 cases out of 60 is acceptable to me.  I've got so many of 30-30 cases around here that it doesn't matter.

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Happy trails.
Bart M

Midway has a supply of .375 cases in stock now. I just ordered 500. After adding shipping to Alaska it worked out to .35c a case.  If yu have the means I would be interested in having you section one of the fire formed .30-30 and .38-55 cases. Then compare the case thickness to that of a .375 case and unformed .30-30 cases. I am wonder how thin the formed cases will be compared to an standard .30-30 and standard .375 case.  This might give a clue as to how strong the formed case will be.  I have had people on other forums say that after forming the cases are weaker then is safe to use for .375 loads.

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FA18CUB

I don't really have a decent way to section these cases. *Have tried this with a hacksaw before but that usually just results in a burred cut that wouldn't lend itself to accurate measurement. *I've heard people talk on both sides of this case strength issue. *Paco Kelley says it's no problem, and he hotrods his loads. *I believe I've seen Marshall say similar things. *Have seen lots of people on the web say just the opposite. *I gather that none of these people have tried it themselves and therefore have no practical data. *My stance is that if it bothers you then don't do it. *I usually keep my loads below max and haven't seen anything that even hints of problems. *My standard elk load has been a BTB 250 gr over 35.7gr of Re7. *This clocks about 2050 fps which isn't really top end I'm sure. *I've also loaded Bonus Bullet's 260 gr RNFPGC over 33.7 gr of Re7. *Didn't chrony this one but it kicks hard. *The Bonus bullet seats much deeper in the case than Marshall's. *I haven't had problems with separation or loose primer pockets. *Usually these fireformed cases will start to split at the neck from being expanded/crimped, and sometimes they'll split on forming. *I bought 20 38-55 cases over 1 1/2 years ago and am still loading 14 of them. *They've been loaded fairly hot at least 10 times each, and probably many more...haven't kept track. *I lost 5 of these to neck splits and one to a poorly adjusted crimp die.

Hope this helps. *You've got to feel comfortable with safety in this hobby so don't try it if it doesn't sit right with you. *Like you said, 375 Win cases are available and there's nothing wrong with using them...I've got about 100 of them myself.

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Happy trails.
Bart M

Chris,

I started with virgin Remington .30-30 cases one time, and for a pure test of the cases, after fire-forming, I loaded them full-snort with a very stiff load (beyond my working accuracy load by a fair margin) of AA 1680 powder, and WLRP with our .378"-250g LFNGC bullet.

I loaded and fired these cases repeatedly, using minimal case mouth flaring to start bullets.  I'm not looking at my notes, but I had one mouth begin to crack at about nine loadings, two case mouths fail at around the fifteen load mark and the remaining two went to twenty loads with no undue signs of stress, cracks, primer pocket enlargement, case head expansion or any other warning indicator that would set up warning bells or caution flags.  I simply pitched the cases after the 20th full load was fired through them.

Now, I know that this isn't a scientificly conclusive test, however, it did satisfy my own concerns for the safety of the practice of using .30-30 brass, fireformed in the .375 Winchester.  Once again I undersore satisfied my concerns as mentioned, you must be comfortable with your own loading practices, all I can do is share my experiences.

Hope this helps!

God Bless,

Marshall

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Marshall
Romans 1:16



Beartooth: A Bullet Worth Waiting For!

Marshall has a good point.  Every so often, people get their shorts in a knot over 'weak brass.'

I gotta tell ya.... if the only margin of safety you have is 0.015" of cartridge brass... you are doing something WAY wrong!

The steel in the chamber and receiver is what contains the pressure.  As long as the chamber is cut within spec, your brass is not going to be a weak link at reasonable pressures (ie not blowing primers).  And that pressure, friends, is WAY more than you ever want to see in any lever gun.

Only guns 'designed' on purpose for the brass to hang out unsupported are exceptions to this, like the 1911 .45 ACP which of course is shooting a catridge in the 20,000CUP range.

Glocks are somewhat known for having chambers a little oversized and they will leave brass looking a little 'pregnant' at top loads but that's not what we're talking about here.

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MikeG