Getting the 375 H&H ready

Brad

Benevolent Overlord and site owner
Staff member
I decided to get back to shooting with the 375. I own a 270 gr mould from MP but hadn't cast with it much. I decided to use the flat nose pins instead of HP. I wanted to make casting easier to get the best bullets possible.
I used some advice from Ian and Fiver and slowed down my cadence. I was casting too fast and that was leading to excessive mould heat and I got some rounded bands and small flaws in bullets. Too much mould heat tends to do that.
I poured lead from the ladle for a 2 count, let the sprue set for a 5 count, dumped bullets, and waited another 5 count before pouring again. I used a small fan on the mould during the cooling periods. Results were amazing. Bullets all weighed 269.2 to 270.3. I can't argue with those results.

An unsized bullet next to a sized and check bullet. Checks snap on the shank well but remain loose enough to spin after sizing.
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Notice the small flaw in the lower portion of the grease groove? The photo doesn't show it as well as I can see with the naked eye. This is what I get, along with rounded bands, from excessive mould heat.

Next time I cast these I may reduce the pot to 675 from 700 to reduce the heat being poured into the mould.

These will get loaded over enough RE 17 to get into the 2200 fps range. The rifle is heavy enough to make those loaded very manageable.
 

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gman

Well-Known Member
I believe a small fan is what I need when I cast with my MP mold for my 480 Ruger. This last casting session was much better but I believe that may be the answer. Good timing Brad!
 

Brad

Benevolent Overlord and site owner
Staff member
Try really slowing the process too. Pour, let it sit for maybe a 7 count, cut and dump, wait 7 then pour again.
Bullets will hopefully all have an even sheen to them and no round, frost edges on bands.
I find I cast too fast on the whole.
 

Will

Well-Known Member
Brad a 270gr bullet at 2200fps should put a hurting on anything it’s pointed at.

I’m surprised the recoil is that manageable with a heavy bullet going that fast. When I get 300gr bullets up around 1700fps in my 1895 the fun stops pretty quickly.
 

Brad

Benevolent Overlord and site owner
Staff member
An extra couple of pounds and a well designed stock and recoil pad make a huge difference. This rifle has a reasonably heavy 26" barrel and a hefty stock.
Rifle is a CZ550 Safari American.
A 270 gr bullet at 1800 is a real pussycat in this rifle.
 

Will

Well-Known Member
That bullet looks great I’m anxious to see your results.

I am also looking at ways to refine my casting. I tend to run my molds to hot using the ladle. Problem is with some of my 30 cal brass molds I can’t hardly run them fast enough to keep the mold throwing good bullets.
 

Brad

Benevolent Overlord and site owner
Staff member
Ok fiver, what are you seeing?
I see a mould hot spot that caused a little void on the surface in the groove. The band below the groove isn't square, also from excessive mould temp in that are?
The bullet does show slight differences in sheen/frosting. Variations exist along the length of the bullet.

What made me pay more attention was your comments to Walter regarding his 30xcb bullets. A visual examination is more than looking for obvious flaws.
 
F

freebullet

Guest
Y'all would cringe if you seen my 9mm bottom pour for volume runs.

I've been enjoying learning/testing the finer points. The better each of us get, the better we will all be. I still can't claim to cast within 1gr, that's some impressive work, Brad.:cool:
 

Will

Well-Known Member
Fiver I would also like to hear you weigh in on Brad’s question.

This is an area where I know I need some improvement not only with slowing my cadence but really reading what the bullets I’m producing are telling me about mold temp.

So far my biggest help was going to the large ladle. I saw a quick improvement in bullet weight spread, but feel I still have lots to learn.
 

oscarflytyer

Well-Known Member
One of the nicest rifle calibers I ever got to shoot. BIG bore, I didn't think it recoiled as bad/anymore than a 30-06 or my 300 Win Mag with high comb Bell and Carlson stock (which cut felt recoil to less than a std 30-06!). Bet it would be a blast to shoot cast in - much like light Trapdoor 45-70 loads I shoot in my Marlin!
 

KHornet

Well-Known Member
I have Lyman 375449 double, and single in HP, as a solid weighs about 275, HP about 265. Took a nice deer with the HP over 2400, cant recall the load offhand, but the deer was 110yds off hand, High lung shot, 37 cal in, and about 45-50 exit, and a flop kill. I killed my Cape Buffalo in Zimbabwe with Brads Rifle and 300 gr. Hor Soft point, but if I had to do it over again would have used full jacket. I shot a lot with that rifle before the hunt, with the deer load, as it is much easier on the shoulder than full power loads. The 375H&H is one of THE great cartridges of the world. In my #1 Ruger 375H&H I have shot every thing from round ball to full power 300 grainers. My first 375H&H was a Browning that I killed my Kodiak with. Wish I had kept that rifle, along with a lot of others that went down the road.

Paul
 

fiver

Well-Known Member
it's an external void.
like the alloy splashes right there and rolls back out again going somewhere else then air gets trapped.
kind of like those little worm holes on the surface along the base of some bullets.
pour slower and see what happens.
I even get the COME ON GIVE ME SOME ALLOY syndrome when I'm casting.
I have my LEE turned down so low I think the spout is plugged sometimes.

sometimes a quick fill or a bit of pressure is what a mold likes, but I ain't ever had a problem going slow, as long as I pay attention to the appearance of what is coming out of the cavity's.
 

waco

Springfield, Oregon
Interesting stuff. I will try some different techniques next time Irun the XCB mold. I think I had too much heat in the mold too. I was having to wait a long time to see the sprue frost over.
 

Will

Well-Known Member
I do the same thing Waco. I need a clock to keep track of wait between pour, sprue cut, and refill.

I have a hard time being patient.
 

fiver

Well-Known Member
took me about 2 hours to make @5 lbs of 165gr bullets today if that gives you a clue.
I spent about every third-fourth pour cooling down the mold a bit.
that's with a 5 count after flash over and an alloy temp of about 680-F.
 

Brad

Benevolent Overlord and site owner
Staff member
How many cavities?

My 375 mould is brass and a 2 cav. It heats up fast and that much lead going in each pour keeps it hot. Since I use a ladle I need to make sure I don't pour lead over the mould too long or it just heats up more.
 

fiver

Well-Known Member
2 cavity's.
I only have 1- 4 cavity rifle mold, no wait 2,,, they are both old walt melander NEI's, and a single 3 cavity accurate for the Argie rifles.
other than those all of my rifle molds are either 1 or 2 cavity.
I am starting to lean more and more towards 1 cavity for 1 rifle.


when I run the 4 cav molds for the lever guns I keep a wet rag on a side stool so I can keep the temps under control.
 

Brad

Benevolent Overlord and site owner
Staff member
I have considered a wet rag but don't want to create hot and cold spots in the mould.
A small fan and time seems to make do. I will be using a slightly lower temp next time.