375 Winchester from 30/30

[Blanco]

I had an interesting exchange with Tom at Accurate
He said that both Winchester and Marlin just rechambered 38-55 barrels in a lot of rifles. The rub is if you go by engineering specs the .375 bullet is just barely kissing if touching at all on the rifling.
He said that he has done a lot of testing and found that the only way to get any accuracy was to use a bullet of .380 dia. He said he uses the 30/30 brass along with a long bore riding nose 250 gr. .380 bullet seated as far out as possible.
So I will definitely slug the barrel first

[Blanco]

Something else interesting
Just got the new Lee catalog in and there is a Boolit mold in 375/ 38-55 (May be an old design, just never noticed it)
I might have to look very closely at this one......
Might put feelers out and see if someone who has it would be willing to send / sell me a few slugs?

[shdwlkr]

blanco
I have a mold that produces 300 grain .379 bullets and bought some 350 grain .379 bullets that I have yet to try. College and kids and having to find a new place to rent every year makes it hard to get into casting and reloading but the good Lord willing I will be done with college in a few weeks and there will be more free time.
I also have a 248 and 264 grain I think it is in .375 caliber from what I have read the heavier the bullet the better the .375 likes it. Mine are earlier manufacture so I would not be surprised to find they are really 38-55 length as I am sure that is what Winchester did at first, my smith at the time thought so too, he was sure that there was enough room to put the 38-55 cartridge in the rifle. We never did get a chance to test it though he got cancer and I lost him.

[nanuk]

when one shortens a case and then sets the projectile deeper than standard o.a.l. using the same charge weight pressure will be raised ,in most cases just setting the projectile deeper raises pressures,some ,such as the hi intensity cartridges ,dramatically so ( aka 9 mm and 40 s&w) ,one is reducing case capacity ,setting the projectile out longer ( with the same charge weight ) usually lowers pressure , this is assuming that you arent setting the projectile out to the lands ,weatherby used a long leade ( freebore ) to help reduce his pressure , the running start does tend to reduce pressure to an extent and this isnt what i'd call a bottleneck cartridge more like an overgrown 357 mag that you'll now be trying to load same said mag load in a 38 special case ....yeah pressure would be

i know it SHOULD work that way but Hornady Ballisticians et al have found the contrary to be true. To understand this you have to disregard the case and think only of the chamber. THAT is what defines the area of contained pressure. Wheatherby freebore makes for a larger chamber. As does firing 357 mag in a Max.

Short brass is irrelevant. Seat a bullet to same COAL and as long as the brass can hold the bullet the preesure WILL be the same.

Giving a bullet a running start allows easier entry into rifing thereby artificially creating more CHAMBER for the pressure before Max pressure and therefore LOWER pressure. A bullet in freebore offers little resistance to pressure. A bullet in rifling, not much more.

I know it is counter to the old wive's tale/myth but that is what the Ballisticians have found. I wish I had a pressure test unit to try some further experiments.
But for now, as long as the Chamber isn't shortened also i would have no issues with short brass and full power loads.

for now i will trust the experts.

[alamogunr]

Nanuk: Is there a paper describing the Hornady findings? This goes contrary to everything I've read or been told. I've always accepted it as gospel.

I would feel more comfortable if I could access a paper that a reputable company had attached their name to and that went into detail about their findings.

Plus, I'm not an experimenter. I wish you had pressure test equipment too!

[Harter66]

Just as a gee wiz ...... 32 Win special is a shorter jump back to straight and might not shrink as much as 30-30 And may have a slightly thicker finished neck.

There is a 6.8 Rem forum that has several builders on it . They also advocate the longer free bore jump to the rifling to increase velocity without raising pressures.

[fryboy]

ummm chop ..** Wheatherby freebore makes for a larger chamber. As does firing 357 mag in a Max.

Short brass is irrelevant. Seat a bullet to same COAL and as long as the brass can hold the bullet the preesure WILL be the same.

*chop..chop
.

but in order to crimp in the jacketed cannalure using shorter brass the o.a.l. will be shorter , put that 357 max load in the 38 special case and tell me that pressure wont doesnt up when you crimp to the cannalure ( just please do not stand beside anyone when you pull that trigger .... )

it's for a lever action so crimping is only prudent ...

[Blanco]

I have been playing with boolit designs again....
Basicallty the Lee Boolit with no luube grooves. Crimp groove moved closer to the middle and a bit more roundness to the nose.
Idea is to use this with the modified 30-30 cases and powder coat
My guess is about 245~250 Grains


Attachment 129416

[Skipper]

Nanuk: Is there a paper describing the Hornady findings? This goes contrary to everything I've read or been told. I've always accepted it as gospel.

I would feel more comfortable if I could access a paper that a reputable company had attached their name to and that went into detail about their findings.

http://www.hornady.com/ballistics-resource/internal

[alamogunr]

http://www.hornady.com/ballistics-resource/internal

Thanks! I just found it a few minutes ago and printed it. Also printed the article on External Ballistics.

After thinking about who might be the source, Hornady came to mind. I don't have time to read it now but will over the next few days.

[Dan Cash]

To feed a .375x2 1/2 inch flanged express, I resorted to nanuk's method, .30-40 Krag ammo; spun the cartridge against a file to reduce rim, loaded it up and pulled the trigger, squared case mouth. Result was 1/4 inch short but I seated the bullet out to standard overall length. Rifle is quite accurate.

[Frank46]

Not to throw a dampener on all this creative thinking but the 375 win case was/is beefed up to take the extra pressure generated by this cartridge. So having said that if all you are doing is 38-55 loadings and pressures then go for it. But as far as taking a reformed 30-30 case and reforming it to 375 win and expect it to serve instead of the origional 375 case then you may have a problem.Just my 2 cents worth. Frank

[Blanco]

Just looking to make the lever gun shootable. I had to have an alternative to no ammo and no components. I was well aware that the 30-30 brass was not as heavy. The loads I am making would just be plinkers.

[longranger]

The problem I have found with reduced loads and cast bullets in my Win.94 B.B. .375 Win. was finding a load that would regulate to the factory barrel sights,without drilling/tapping for after market sights.Using 38-55 load data you will be lucky to be on paper @50 yds. .379 dia. seems to be the prevalent/preferred bullet dia. for cast in the Win. barrels and proven accurate in mine.

[Bent Ramrod]

I have a Hopkins and Allen .38-55 shotgun on the medium frame. At the time I found this gem, .38-55 shells were very seldom seen, so I made them from .30-30 and .32 Spl cases. I annealed the necks with a torch, dried the shells overnight, primed, put in 9 gr Unique with Cream of Wheat to fill the rest of the case, and a wax wad over the end to keep everything in.

The shells blew out to fill the chamber well. A little short, as mentioned, but this is not a benchrest gun, or even a rifle, for that matter. The pressure did not seem excessive, but the fireforming charge can do some real damage at close range. It would blow a hole through one side of a gallon pail at a range of a few inches. Not what I expected from Nonte's book, which said he fired such forming charges in his basement without disturbing the sheets his wife hung down there to dry.

[Harter66]

I formed some 7x57 with a lighter charge than that and experienced a similar event . I never liked that garbage can anyway.

[garandsrus]

The problem I have found with reduced loads and cast bullets in my Win.94 B.B. .375 Win. was finding a load that would regulate to the factory barrel sights,without drilling/tapping for after market sights.Using 38-55 load data you will be lucky to be on paper @50 yds. .379 dia. seems to be the prevalent/preferred bullet dia. for cast in the Win. barrels and proven accurate in mine.

The win 94 BB is already set up for a Lyman peep sight. There are a couple screws on the receiver that come out and the the Lyman sight and it's screws replace them. No modifications are needed and no new holes are added. This is for a top eject model. I don't know if the side eject is the same.

[Elkins45]

FWIW my 375 has never seen a 375 case. I have 100 converted 30-30 cases and 50 38-55 that I use with it. I don't load that light rifle anywhere near max with cast bullets so I don't worry about the slightly shorter or thinner cases. I think of it as shooting 22 long in a 22 LR chamber.

[BAGTIC]

You can stuff more powder in the more voluminous case but OTOH it takes more powder to produce the same velocity.

[BAGTIC]

Mine are set up for a Williams Fool Proof sight. Perhaps both sights have the same hole spacing and thread size.