Accurate 36-270 questions.

CWLONGSHOT

Well-Known Member
Im looking for a heavy 35 for use powdercoated in my 35’s from 356/358-35Whelen and 358 Norma Magnum. For hunting purposes.

This profile should offer enough “size” so I do not need to seat overly deeply.

Anyone have experience with it?

CW
 

CZ93X62

Official forum enigma
There are three "36-270" selections in the catalog. Also not real sure what you are asking.

I do not powder-coat, but I do have GREAT accuracy with a 270 grain flatnose (70% meplat) in 9.3mm caliber. It has shot well from 1400-2000 FPS, by which time it lets you know that the primers fully functioned.
 

Ian

Notorious member
Accurate moulds are just about my all-time favorite moulds, but if you're looking to fit three different throats that might all be vastly different in the fit department, I HIGHLY recommend this MP design right here and you're lucky enough that he actually has some left over from the last group buy, in stock:


I have an original cut by Bruce of BRP moulds, it is designed to be the heaviest bullet that will chamber in a Marlin 336 .35 Remington but due to the complex taper of the nose, it will fit and shoot well in a lot of things.
 

CWLONGSHOT

Well-Known Member
I have a number of molds. But one of my favorites is a problem. Its a NOE 360-280. Its a bore rider and once powder coated its too large.

I have a RcBS 210 thats jut fine but too light for my wants.

I also have a NOE 360-232 that I like alot! Its NOT a problem when powder coated. BUT, Id like 270-280g. This is why I was asking on the 36-270.

CW
 

Ian

Notorious member
That's one of many reasons why I think bore-riding designs are no good. Accurate velocity limitations is the other.

I've been meaning to draw one of these up for a while so I did so on my lunch break. You could use this as a general guide to make a drawing for Tom to go off of if you want to design a new 36-170 bullet:

Tapered nose guide.png
 

Spindrift

Well-Known Member
Ian; that is a very interesting drawing! Sums up and clearifies some concepts that where swirling around in my brain. Thank you, lunch break well spent- hope you got some food too :)
 
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CWLONGSHOT

Well-Known Member
Well. I attempted to order this mold to ight..

But web site kicked me out and will not allow me to start again

I sent a email to Tom...

Maybe I aint supposed to have it! ::)

CW
 

waco

Springfield, Oregon
I have a number of molds. But one of my favorites is a problem. Its a NOE 360-280. Its a bore rider and once powder coated its too large.

I have a RcBS 210 thats jut fine but too light for my wants.

I also have a NOE 360-232 that I like alot! Its NOT a problem when powder coated. BUT, Id like 270-280g. This is why I was asking on the 36-270.

CW
Put some water in a bowl. Float a half teaspoon of powder on top of the water. Hold your bullets by the nose and dip them into the water just up to the top driving portion of the bullet. Stand up to dry and then bake as you normally would. This leaves the bore riding section of the bullet as cast. 8A38D137-D5BB-4D2D-8EA6-303CB9642246.jpeg
 

Ian

Notorious member
Spindrift, this is my interpretation of a successful nose, based on results. Another successful (and quite versatile) design id the MP 30-180 that you have....that one has angle theta at 1⁰ per side and angle delta at 2.5⁰ which makes for a much steeper taper to the nose. I have a variety of custom .30-caliber moulds covering these ranges and one with a straight taper, and three things I've learned: Parallel is no good except at medium to slow velocity, straight taper is usually no good unless the throat is two parallel sections with an abrupt taper to the ball seat area (a mis-match), and straight bore rider with a throat-matching taper up to the full diameter is almost as bad as a two-diameter Barlow design. Further, if the lube grooves are too shallow and/or the driving bands too wide such that alloy has a difficult time getting moved as the bullet engraves the throat, the body of the bullet can get gas cut, pished crooked, or if the alloy is on the softer side the base can rivet. All of these things cause accuracy-destroying damage to the bullet before it is even fully intobthe barrel.

A bullet with two distinct tapers to the nose gives just the right amount of support to guide into the throat with some "wiggle room" to get there without being deformed. If the body of the bullet is designed correctly it can follow the nose through the throat without requiring so much force that it is mangled in the process. Alloy temper and composition plays hugely into this operation as well, too hard and brittle is a no-no as is too soft and gooey, but what alloy works best is determined by the peak pressure value and pressure curve that the chosen powder is providing.
 

Bret4207

At the casting bench in the sky. RIP Bret.
I'm just happy to know there is still some interest int he 358 Norma Mag. That was the hottest thing going in my youth, quite a cartridge.
 

CWLONGSHOT

Well-Known Member
I have wanted one since I was a boy! Reading the accounts i. The gun rags.

Then in ST when they released there own calibers. I started building a 7mm STE then just bought a Waters.
I always like the 280 and the 7mm STW WAS DARN IMPRESSIVE BUT WHEN, I read about the 358 STW. WOAH!! Another twenty years went by untill I have a NM.

Loaded some 190 WFN TRAIL BOSS LOADS to FF some 338 brass.

I like it and its quite a shooter! Testing loads the PO provided Once I hit 71 g 4350 bullets tighened up to touching. Awesome to have a rifle as powerful that such a tack driver too!!

CW
 

CWLONGSHOT

Well-Known Member
Thanknyou for the efforts Ian! Very much appreciated!!

Waco i will try this next time I cast! I should have my mold soon and I will fire up the pot!

CW
 

Ian

Notorious member
Much of the time in this hobby you just have to jump into an idea, spend the money, and give it a shot in order to get your own answers. I admire your willingness to do just that and not wait for someone else to blaze the trail for you. You're in good company here!
 

Spindrift

Well-Known Member
CW, very nice bullets!
I have no .358 rifles myself, but I am considering getting a 35 whelen barrel. The idea is, to have a cartridge that would work with cast bullets on elk-sized game. And that 36-270 WFN bullet seems to be just the ticket. Hmmm, you got me thinking here.....

Pleas keep us posted on your experiences with the bullet. Best of luck!
 

CWLONGSHOT

Well-Known Member
Thank you Spindrift!

I have used another that might also work well
Into your plans. Its a NOE 360-232. Its also a RD design. It has a shorter OAL but wider meplat.

Its the RED bullet in the pic.

The Grey is also a NOE 360-280. Its a copy of the classic Lyman 358008 (I think thats the number)

My problem with that bullet is its a bore rider and as cast the dia is .352. So W/pc its closer to .355/356 and too big to chamber. Otherwise its also a great bullet. I may have to try the PC partial as suggested or just lube to use it.

Good luck

CW9E111E2D-4842-4AB8-86DE-9FFB8BCBA5CB.jpeg
 

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CWLONGSHOT

Well-Known Member
I loaded a shot a couple today even tho I know they need to season more. I was impatient. Just a case if Trail Boss 22.5 fit to bottom of the bullet and gave me 1450fps and 1 - 1.25” 50 yard groups.

This is a fun load but i would really like to be 2000+ fps. I dont think 2200-2300 is out of reality.

Looking last night I did not locate any data at all. In the past I have used 338 mag data (lead) but I dont find anything past 225g bullets.

Extrapolating I believe about 30g of 5744 aughta put me pretty close. Its no mans land.

Any one know of data for this big Norma Magnum and these heavy lead bullets?

Appreciate the help.

CW