quote:

Originally posted by Fury01:
Dang Rip. Making your own Gas Checks from 300 Grain Sierra's and a chrony to catch them, seems kind of radical. Now we know though, it can be done.
All for THE MISSION!

That is double funny. Better to laugh than to cry.

Rip ...

quote:

Originally posted by .458 Only:
The problem with such a fine-grain ball powder as AA1680 is that anything less than 100% load density, after the bullet is seated, will permit the powder to "move around" too much in the case at odd angles when the rifle is fired in anything but a vertical or flat horizontal mode. Thus, erratic MVs, more or sometimes less, depending, of course, on actual load density.

I started off with only 69.0 grains of AA-1680, which is about an 85% fill with either of the bullet-COL combos I used.
81.0 grains would be about a 100% fill with my two bullet-COL combos in the .458 WIN.
Likewise, 82.5 grains for the .45-100 SWT.
Erratic velocities and occasional hangfires resulted with the starting load.
Now I know why Hodgdon says not to reduce from the full-case charge of H110 in the .454 Casull, etc.

With the 300 TSX seated to the bottom cannelure (farthest from the tip), and a COL of 3.327", even 83 grains of 1680 doesn't fill the case. As said; 84.5 gave best results overall, considering case head expansion and MV. But even then from 2 shots, the ES was 19 fps; and that was the best of those fired. Yet, I will try that load for accuracy @ 100 yds. I much prefer, and expect, not more than 10 fps ES from .45-70s and .458s.

However, there were NO signs of excess psi from any loads tried so far from 83, 84, 84.5 and 85 grains behind the 300 TSX in Rem brass, ignited by WLRM primers. The barrel of the Ruger #1 is 24" as all know, I think.

Excellent info.

If I wanted to drive that bullet (300 TSX) slower than my first try (2856 fps), I'd NOT reduce the load of 1680; I'd go to a slower powder with more bulk to it.

H4198 is looking really good again.

But I'm wondering if W680 would give similar results as 1680? They are listed as having the same, or similar burn rate. 680 is also a ball powder, perhaps flattened like other Winchester ball powders. Anyone with experience using 680 in a large bore?

Bob
www.bigbores.ca

Knowledge of W680 in the .458 WIN is above my paygrade.

Rip ...

quote:

Originally posted by 4sixteen:
Re7 would likely provide highest speed at maximum pressure in either .458 WM or .458 Lott. With the 300gr TSX not the 300gr jacketed HP which would disintegrate after leaving the muzzle at speeds > 2800 fps.

Yes, RL-7 might be tops, but H4198 is good enough for 2700 to 2800 fps with the Barnes TSX bullets of 300 to 350 grains weight.
That requires mildly compressed loads with the H4198.
I think it has less lot-to-lot variability and excellent ThermoBallisticIndependence, compared to RL-7.

Funny how I used H4198 to get the Sierra 300-grain Pro-Hunter up to 2755 fps in the .458 WIN, Chimera WinCZechster, with 24.875" CZ barrel.
No mid-air-exploding Sierra bullet until about 2800 fps MV with AA-1680.
I hate it when the bullet explodes inside a muzzle brake.

Rip ...

quote:

Originally posted by RIP:

quote:

Originally posted by Cold Trigger Finger:
I had vastly superior penetration from a 180 gr fmj40 cal bullet @ about 940 fps. From a striker fired pistol.

Did that pistol load exit a ProChrono?
Funny how most of the .458 WIN load that exploded in the muzzlebrake went about a foot low at 5 yards, and only penetrated a few inches of plastic and electronics.
Base of the bullet jacket was lying on the grass in front of the toppled-over tripod.



Rip ...

Yes, in the front and out the back. Made a bigger mess than when I've shot Chrony's .

quote:

Originally posted by RIP:

quote:

Originally posted by 4sixteen:
Re7 would likely provide highest speed at maximum pressure in either .458 WM or .458 Lott. With the 300gr TSX not the 300gr jacketed HP which would disintegrate after leaving the muzzle at speeds > 2800 fps.

Yes, RL-7 might be tops, but H4198 is good enough for 2700 to 2800 fps with the Barnes TSX bullets of 300 to 350 grains weight.
That requires mildly compressed loads with the H4198.
I think it has less lot-to-lot variability and excellent ThermoBallisticIndependence, compared to RL-7.

Funny how I used H4198 to get the Sierra 300-grain Pro-Hunter up to 2755 fps in the .458 WIN, Chimera WinCZechster, with 24.875" CZ barrel.
No mid-air-exploding Sierra bullet until about 2800 fps MV with AA-1680.
I hate it when the bullet explodes inside a muzzle brake.

Rip ...

Just too much torque on that little bullet. It reminds me that the Berry''s 350 gr plated 458 bullet has a 2200 fps velocity ceiling on them. I was shooting them at 2400 fps and didn't have any problems. But I'll probably slow them down to 2200 fps. Don't want any obstructions in my brake.

quote:

Originally posted by RIP:

quote:

Originally posted by Cold Trigger Finger:
I'm not knowledgeable enough to use 1680 in a 458. So I will watch and learn. !

My similar knowledge base did not stop me from trying the AA-1680 in a .458 WIN.
I am still learning too.
Trying it with cheap bullets for this lesson was false economy, unfortunately.
Will resume with the Barnes TTSX or TSX 300-grainer for the next lesson with AA-1680
here at The School of Hard Knocks.



Rip ...

I wish I had kept more organized data with mine.

While on the subject of things in the bore. Does anyone know if those electric bore cleaners ( I think they were called Foul Out ?? Will lift moly out of a barrel ?
The system where one end of the barrel was plugged and a solution was poured in the barrel. Then an electric rod was inserted and plugged in.
The metal fouling build up in the bore was electrically transferred to the inserted rod.
I would like to really clean Spruce King's barrel all the was down to the stainless so I can start from ground zero recoating it with HBN.
SK has had Lots of Molly tumbled bullets down the barrel and has always thrown the cold bore shot outside of the group by a bit.

Well, I'm not sure that my experiences using the 300 TSX over AA1680 is helpful or unhealthy, but for the record (so far) I went to 86 grains today, starting at 84.5, as promised.

From previous tests, starting at 83 -shooting one, I got 2856 fps corrected to MV. That worked out to an average of 34.4 fps per grain of AA1680. A subsequent test of 84.5 and 85 came close enough to that benchmark; especially 85 grains at 2906 fps average.

As promised, I retried 84.5 today as that seemed last time as likely to be best (or better) than 84 or 85 tried previously. It turned out to be a bit slower (3 shots) on average than the previous try by 33 fps. But it showed promise for accuracy. I used the Lead Sled, which I've discovered is not the best idea for testing accuracy (more on that another time).

My second load today was 85.5 grains (last time 85 grains was the highest), which came within a few fps of prediction based on 34.4 fps per grain. That load worked out to 2954 fps corrected to muzzle speed. My prediction was 2941 fps based on 34.4 fps per grain. That's close enough, and 5812 ft-lbs KE.

The final load (one shot) was 86 grains. I'll not publish what the Chrony result was, but I didn't shoot my Chrony! It worked as expected for all shots, including the 86 grain load. But the speed recorded was unexpected and well beyond the predicted result based on 34.4 fps per grain. I think it may have been a false reading as the recoil was only a bit more than the others; and the case extraction was normal (practically fell from chamber) and head expansion is normal compared to the others. In fact, recoil, case extraction and head expansion has been less for these loads than for some of the heavy bullets (450 to 500gr) at max velocity.

I was hoping for about 3000 fps for the 86-grain load behind the 300 TSX.

The Chrony far exceeded that! But everything was "normal" otherwise. So, what I have to do now is retest that particular load. I'll shoot several to get a realistic view of what was going on with that load. I'll report results. But, I have to find a fresh can of AA1680 because what I've been using was borrowed from son Phil who uses it in his .17 Hornet.

But to emphasise: there was nothing abnormal for that load other than the Chrony readout.

Another point: I don't initially shoot a whole bunch of the same load. That's a waste of expensive bullets. Unless I have a lot of experience with a particular rifle, cartridge and powder, I start load development with a single shot, or perhaps two. That will give me a ballpark figure. I work from there depending on first results.

AA1680 is a relatively new powder, and was not developed for the .458 Win, nor was any other powder mainly suited to .223s, but they often work best in cartridges like the .45-70 and .458 with heavy loads. Powders like RL-15 are too slow for max results in either of those two cartridges. I use RL-15 (reduced loads) in the 458 shooting relatively heavy bullets (400s and up) at less than 2000 fps.

Bob
www.bigbores.ca

quote:

Originally posted by Cold Trigger Finger:
Just too much torque on that little bullet. It reminds me that the Berry''s 350 gr plated 458 bullet has a 2200 fps velocity ceiling on them. I was shooting them at 2400 fps and didn't have any problems. But I'll probably slow them down to 2200 fps. Don't want any obstructions in my brake.

That is wise.
Nice 350-grain plinker.
No relation to Berry's Bullets,
but I stop at 2200 fps with my 545-grain, hard-cast, powder-coat-painted, heat-treated, gas-checked, flat-nosed, home-made bullets too,
even though the .458 WIN LongCOL can safely move them close to 2300 fps with AA-2460.

Rip ...

quote:

Originally posted by Cold Trigger Finger:
While on the subject of things in the bore. Does anyone know if those electric bore cleaners ( I think they were called Foul Out ?? Will lift moly out of a barrel?
The system where one end of the barrel was plugged and a solution was poured in the barrel. Then an electric rod was inserted and plugged in.
The metal fouling build up in the bore was electrically transferred to the inserted rod.

Outer's Foul Out System, IIRC.
Chuck Hawks mentioned once that using the foam bore cleaner WIPE-OUT after the Outer's electrochemical thing
showed that WIPE-OUT was better.

I would like to really clean Spruce King's barrel all the was down to the stainless so I can start from ground zero recoating it with HBN.
SK has had Lots of Molly tumbled bullets down the barrel and has always thrown the cold bore shot outside of the group by a bit.

The old method was soak the barrel overnight in Kroil (with barrel plugged) and then scrub it out with JB paste and Kroil mixture, then use the Hoppe's No. 9 and/or ammonia-containing bore cleaner after that.

I think WIPE-OUT claims to remove moly fouling, and it does it with a lot less elbow grease.

Rip ...

quote:

Originally posted by .458 Only:
Well, I'm not sure that my experiences using the 300 TSX over AA1680 is helpful or unhealthy, but for the record (so far) I went to 86 grains today, starting at 84.5, as promised ...
... I was hoping for about 3000 fps for the 86-grain load behind the 300 TSX.

The Chrony far exceeded that!

As you say, maybe an instrument error, only one shot, and sometimes "blank" happens.
Or it was not an error and it is a warning that the "blank" is getting close to the fan?

But everything was "normal" otherwise. So, what I have to do now is retest that particular load. I'll shoot several to get a realistic view of what was going on with that load. I'll report results. But, I have to find a fresh can of AA1680 because what I've been using was borrowed from son Phil who uses it in his .17 Hornet.

But to emphasise: there was nothing abnormal for that load other than the Chrony readout.

Another point: I don't initially shoot a whole bunch of the same load. That's a waste of expensive bullets. Unless I have a lot of experience with a particular rifle, cartridge and powder, I start load development with a single shot, or perhaps two. That will give me a ballpark figure. I work from there depending on first results.

AA1680 is a relatively new powder, and was not developed for the .458 Win, nor was any other powder mainly suited to .223s, but they often work best in cartridges like the .45-70 and .458 with heavy loads. Powders like RL-15 are too slow for max results in either of those two cartridges. I use RL-15 (reduced loads) in the 458 shooting relatively heavy bullets (400s and up) at less than 2000 fps.

Bob
www.bigbores.ca

I only had 1-pound of AA-1680, used little of it in the .475 Linebaugh.
I have an 8-pound jug of H4198, which now seems plumb slow and bulky for a 300-grainer in the .458 WIN.

Rip ...

quote:

Originally posted by pavementends1:
Has anyone tried the 300gr Nosler RN in the .458?

pavementends1,

This got lost in the flurry of powdered bullets.
Surely for 300-grainer at 2800-2900 fps, a Nosler partition would be less likely to explode at the muzzle.



Not sure about the Nosler Ballistic tip, despite their generic claim for velocity window:
Minimum: 1800 fps
Maximum 3200 fps



May The Force-458 be with Obi-Wan Bob, and may he pull the trigger with 50 feet of string from behind a tree on his next 86.0 grains of AA-1680,
with 300-grain TSX in the .458 WIN.

71.0 grains of H4198 was a 0.54-MOA 3-shotter at 2638 fps MV with the 300-grain TTSX at 3.395" LongCOL.
For 2500-2550 fps with about any 300-grainer at 3.340" or less COL (2.940" with the Sierra bomb):
68.0 grains of H4198

That would be like SAAMI restricted.
Even the Sierra can survive that.
If that won't do the particular job at hand, use a heavier bullet,
higher pressures,
longer COL.
The possibilities are many with The Force-458.


Rip ...

Nothing to add regarding the topic today.

Just posting "for the mission".

quote:

Originally posted by Todd Williams:
Nothing to add regarding the topic today.

Just posting "for the mission".

Thanks, Todd, for turning the page, for THE MISSION.
This deserves another picture of OL'UGLY from the .458 WIN Archives.

From Phil Shoemaker's article in RIFLE 242, Jan-Feb 2009, "A Season with the .375 Ruger":



IIRC:

.458 WIN Mauser 98: 21" barrel and about 9 pounds, field ready (lead added to stock for balance, which is a Brown Precision with special paint job), ~13.5" LOP.

.375 Ruger M77 Hawkeye Alaskan: 20" barrel and 7.25 lbs bare/dry/empty (Hogue stock replaced with lighter factory synthetic/Tupperware from Brownell's), ~13.5" LOP.

Same LOP was used on Big Nan by Hal Waugh.
Good for winter jacket in Alaska.
Put a slip-on pad on them for T-shirt shooting in Africa.
Trophy fee for a T-shirt in Africa?

Rip ...

Notice the tiny peep sight on the rear Weaver base of OL'UGLY in photo above.
Here is one of the same on my first ever dalliance with a gunsmith, Willis Fowler in Anchorage, Alaska in 1987.
I had him re-chamber a .375 H&H Whitworth to .375 WBY.
He had some of those little peeps in his inventory:

Willis said he was allergic to epoxy so that left me to glass bed and finish my first-ever Brown Precision stock.
I used the now defunct, brown-colored "Micro-Bed" epoxy for the bedding,
and smeared some more epoxy on the exterior grip panel areas and roughed it up, then painted the stock black with Krylon from the BX:

Wallah!
My Ol'Ugly before I knew of Phil's OL'UGLY,
or did I subconsciously pattern it after some aspects of OL'UGLY?
I might have read Phil's description in the September-October 1985 Rifle 101, "Alaska Guide Builds a Modern Backup Rifle."
When that hit the news stands, I was driving from Missouri to Alaska with wife, 4-year-old daughter, and 3-month-old son, suckling all the way.
I am sure I found it in Anchorage after I got there.
Just do not recall.



I hunted Kodiak deer with it in 1987,
my second trip to Kodiak.
It replaced the .340 Wby Fibermark of 1986 Kodiak deer hunt.
I must have been influenced by Ross Seyfried on that one.
Using the .375 Wby Ol'Ugly with the 300-grain Swift A-Frame, a side-shot at the top of the heart broke the spine too. DRT, and nearly cut in half.

Now, see how Todd has given me an excuse to add more replys, for THE MISSION.
And, I now have an inspiration to re-barrel my Ol'Ugly to .458 WIN, with 21" barrel length.
With the 3.6" box length, it will beat any SAAMI .458 Lott with the heavy bullets,
and do all I want to do with the light bullets.

M70-style safeties for Mausers are easy to find.

I need to strip the black paint off to bare, brown-colored, unfilled fiberglass of Brown Precision ilk, like Phil's,
and then go at it with the rainbow Krylon camo.
A piece of Picatinny rail will stick out from the forend tip under the barrel too,
like in latest photos of OL'UGLY.
I could make it a 1:10" twist for subsonic experiments.
Might not be too good for cast bullets,
but that is OK.
My .458 B&M with 1:10" twist, 19.75" barrel length, was excellent with 450-grain North Fork bullets,
but of course, nowhere near as powerful and versatile as a .458 WIN, even a SAAMI restricted .458 WIN.
My first "custom rifle" could become my last "custom rifle."
Saving the best for last, all else would be twaddle.

Rip ...

But first we have a spare Ruger No.1 action with nice walnut stock, and a Pedersoli take-off barrel, full octagon, straight taper, 30 inches long,
1:18" twist, .458" groove and .450" bore.
Hope the local Wizard can work some magic and make up a 28"-barreled .45-100 SWT/.458 WIN ballistic twin for use with paper-patched bullets and duplexed BP.



A Picatinny on the barrel will serve for modern scope.
A long range Soule sight will be mounted on the stock for back-position shooting, aka the Farquharson-turnip-carving-position.
Maybe try that first on the B&C synthetic before doing it to the walnut.
Will see how that works out in a tree stand.

Rip ...

What is the shortest length of barrel to obtain 450@ 2150? 20”? Imagining what a lightweight stalking 458WM would look like.

The 86 grain load was about 100% density. The case was Remington. From experience, they've proved to be stronger than Winchester while holding 1-grain less of H2o. With ball powders I don't like (trust) reduced loads.

A couple of things to keep in mind when loading relatively short bullets in the .458: 1) They have a low SD. In 300gr it's .204. That's a factor in helping to keep psi relatively low. 2) Due to the long throat of the .458 Win, even the 300 TSX seated to the bottom cannelure, is no longer than SAAMI COL of 3.34" employing 500s. That means a very long "freebore" to keep pressures controlled.

Thus, it has been difficult to find a suitable rifle powder that exploits the best from relatively light bullets, such as a 250 or 300 bronze or copper that will in turn stand up to high velocities. RL7 is not it! I tried that and you will run out of powder space before it can match the results of H4198. Then, as RIP mentioned, it is subject to temps variability.

Generally speaking, shooters and hunters who have used the .458 Win were stuck with poor information (and results) for handloading this great cartridge.

However, it's been the ordinary guy who has often ventured in experimenting with powders and bullets that have brought about a change in perception of what a .45-70 or .458(or other Big Bores) is truly capable of. It's not the pros, at least it's not published for fear of litigation.

Actually, I'm a cautious guy and not one to throw caution to the breeze. But my results for the .45-70 in a Ruger #1 (unmodified) was simply the results of testing and logic. The pros who tested my results were astounded even though I was using one of their powders! I was getting from a 500gr Hornady fired in a factory chambered 22" barrel what was being published for a 24" barrelled .458 Win Mag in reloading manuals. And the head ballistician pronounced it "safe"!

I know for a fact that a very well known member of this forum, and a pro, loaded an 1895 Marlin, shooting the 500gr Hornady at 1900 fps for his "boss", who was an outfitter in Alaska. His boss requested it, because "that guy" could do it for protection against big bears. That was a long time ago, and the Marlin never broke, BUT he did not publish it or recommend it!

I'm not recommending anything -- only reporting. On the website of gun powder companies, or distributors, this is in essence their warning (not a verbatim quote): The manufacturer will NOT be held responsible for the use or misuse of this product. The seller and the buyer are the only individuals to be held accountable for its distribution and use.

What anyone does with the reports I make is on them!

I don't assume that people think or investigate as I do, but I try to give a rationale for anything I publish or say.

But RIP is to be praised for taking this theme far beyond my expectations or abilities. Especially is that so in the area of history and degree of testing.

Thanks RIP; you've taken a thread that could have ended a hundred pages ago and made it into an encyclopedia! And thanks to the others who have supported this "Mission", and added their insights and experiences. I personally, have appreciated CFT's experiences and candid (Alaskan type) remarks!

Bob

www.bigbores.ca

nufacturerHodgdon
PowderH4198
Bullet Diameter.458"
C.O.L.3.200"
Starting Load
Grains68.0
Velocity (ft/s)2,565
Pressure40,300 CUP
Maximum Load
Grains76.0C
Velocity (ft/s)2,793
Pressure51,300 CUP
BULLET WEIGHT300 GR. BAR TTSX BT
ManufacturerHodgdon
PowderH322
Bullet Diameter.458"
C.O.L.3.300"
Starting Load
Grains71.0
Velocity (ft/s)2,447
Pressure36,900 CUP
Maximum Load
Grains75.0C
Velocity (ft/s)2,561
Pressure41,200 CUP
BULLET WEIGHT300 GR. BAR TTSX BT
ManufacturerIMR
PowderIMR 4198
Bullet Diameter.458"
C.O.L.3.300"
Starting Load
Grains68.0
Velocity (ft/s)2,559
Pressure39,000 CUP
Maximum Load
Grains70.0C
Velocity (ft/s)2,617
Pressure44,600 CUP
BULLET WEIGHT300 GR. BAR TTSX BT
ManufacturerHodgdon
PowderH4198
Bullet Diameter.458"
C.O.L.3.300"
Starting Load
Grains68.0
Velocity (ft/s)2,591
Pressure40,900 CUP
Maximum Load
Grains72.5C
Velocity (ft/s)2,720
Pressure49,100 CUP
BULLET WEIGHT300 GR. MEI LFP
ManufacturerHodgdon
PowderTrail Boss
Bullet Diameter.458"
C.O.L.2.885"
Starting Load
Grains19.0
Velocity (ft/s)1,187
Pressure10,800 CUP
Maximum Load
Grains23.0
Velocity (ft/s)1,282
Pressure13,200 CUP

Interesting that Hodgdon shows different load data for the 300 gr tsx and the 300 gr TTSX.
H4198 pushes the TSX to nearly 2800. With normal oal. So that is encouraging ey.

Thanks for the tip about Wipe Out. I'll get some in Delta or Fairbanks. Clean all my barrels down to bare steel and give them a good coating of HBN first then shoot only HBN tumbled bullets for a while before I finish shooting my remaining only tumbled bullets. Maybe I'll hold off on my 416 as I have Lots of Molly tumbled bullets for it.

Thanks for the reply, I rally wish there was a 450-480gr non-premium bullet designed for 2300-2500 fps.

I wonder how the 480 gr Hornady bullet works in the 458 Win ?

quote:

Originally posted by boom stick:
What is the shortest length of barrel to obtain 450@ 2150? 20”? Imagining what a lightweight stalking 458WM would look like.

Interesting concept.

The .458 WIN LongCOL can easily do this with AA-2230, if QuickLOAD can be relied upon to predict effect of barrel shortening on MV:
450-grain Barnes TSX at 3.680" COL:
25" barrel: 2450 fps MV
24": 2435
23": 2419
22": 2402
21": 2384
20": 2364
19": 2343
18": 2320
17": 2295
16": 2268
15": 2238
14": 2205
13": 2167
12": 2125

2300 fps with a SAAMI shortCOL .458 WIN and 24" barrel is routine, with 450-grainer.

boom stick's BOOM STICK could do 2150 with the correct 450-grain bullet load in a 16" barrel, most likely,
with an all-the-way SAAMI .458 WIN.

Rip ...

CTF,

Obi-Wan Bob has pronounced the 480-grainers by Hornady to be The Bees' Knees.
If I did not have so many 450-grainers and 500-grainers I could go for the 480-grainers with gusto.

Rip ...

Bob,

Thanks. You are the "mentor" here.


Rip ...

An 18” trim and lightweight thumper would be a fun gun. A steady diet of 45-70 bullets and heavies when needed.

quote:

Originally posted by RIP:

quote:

Originally posted by boom stick:
What is the shortest length of barrel to obtain 450@ 2150? 20”? Imagining what a lightweight stalking 458WM would look like.

Interesting concept.

The .458 WIN LongCOL can easily do this with AA-2230, if QuickLOAD can be relied upon to predict effect of barrel shortening on MV:
450-grain Barnes TSX at 3.680" COL:
25" barrel: 2450 fps MV
24": 2435
23": 2419
22": 2402
21": 2384
20": 2364
19": 2343
18": 2320
17": 2295
16": 2268
15": 2238
14": 2205
13": 2167
12": 2125

2300 fps with a SAAMI shortCOL .458 WIN and 24" barrel is routine, with 450-grainer.

boom stick's BOOM STICK could do 2150 with the correct 450-grain bullet load in a 16" barrel, most likely,
with an all-the-way SAAMI .458 WIN.

Rip ...

After a night's sleep, further reflection, measurements of head expansion (and some prayer), I've decided that 84.5 grains of AA1680 will be considered max in my rifle with the components and ambient conditions of the test period. MV is quite consistent and accuracy looks promising. So will give that load further trials. MV was +/- 2900 fps.

However, I've checked the Remington case carefully in which I loaded 86 grains, and there doesn't appear to be any problems with it in the aftermath of over 3000 fps from the muzzle of my Ruger #1 in .458.

In fact, I've resized it and seated a new primer. It only needs slight trimming.

But, sometime down the road, I'll give another try of the 86 grain load to satisfy my curiosity (if the LORD is willing!).

For the curious: the Chrony reading was 3080 !!! Add 20 fps to that for correction to the muzzle and the answer would be 3100/6400 ft-lbs !!!

Obviously, there was something wrong with that!

If that were a correct reading, then how do I understand/interpret the fact that case head expansion was less than the AA2230 load of 77 grains behind the 500 Speer that gave 2311 fps? That case (the AA2230 load) is reusable, but the primer pocket was expanded enough that I will not use it for max loads again. In fact, head expansion, for the Rem case containing 86 grains, was less than a number of other loads tried, and the case would have fallen out of the chamber had I pointed the rifle in a vertical direction. But that wasn't practical since it was held in place by a strap over the barrel. I just flicked the case out with my finger nail. So, there are mysteries!

AA1680 is made in St. Marks, Fl., so I'm not aware of its ability to resist temperature changes. But that will come with experience. It was made for large bore pistol cartridges such as the 454 Casull. Hornady handbook, 9th edition, shows its use in the 500 S&W for the heaviest bullets giving best results. I've already mentioned that in Barnes #4 they used it for the .45-70, giving results similar to H4198, using near identical loads but at less case volume.

In Barnes #3, 85 grains of H4198 was used for the 300gr XFB (forerunner of the TSX) for an MV of 2849 fps from the .458 Lott. They used a 26" barrel. 84.5 grains of AA1680 gave +/- 2900 fps from the 300 TSX in my 24", as mentioned. Any clues there? Of course, 85 grains of H4198 can't be loaded in the .458 Win case with a bullet seated. That's why I'm giving AA1680 a trial with that bullet.

Bob

www.bigbores.ca

Bob; sounds like you are doing your homework with the Accurate 1680/ 300 gr TSX.
For the longest time EXPRESS loads have gotten ignored. ( and if a 300 gr 458 bullet @ 2900 fps ain't a modern EXPRESS load I would like to know what is. )
Now with modern monometal bullets we can enjoy big bore smack down on soft skinned game. Without getting the bo bangles kicked out of us.
Imho you got a easy pie 300 yard moose smaker. If that load is akrit. And a 15' brown bear stopper weather its akrit or not !

quote:

Originally posted by 4sixteen:
Not quite seeing the need for the ongoing ultra speed theme with the .458's. For example downed a Moose at about 75 meters with the Hornady 500gr RN at only 1900 fps muzzle speed. Boom! Flop! Went clear through broadside. Busted up bone and blood pool. Speed is fine. Accuracy is final. So the saying goes.

Here's how my .458 WM shoots off the bench at 100 and 200 meters. Speer 350gr and Re7.

4sixteen; you are correct of course.
However, it is nice to remove a couple of the remaining "stipulations" from the 458 Win mag.
Those being steep trajectory and heavy recoil.
When I get my 458 back into service. It will be nice to have some more velocity to attain to. Maybe I'm not done with being a velocifile.
Sure beats the halibut out of the loading manuals detuneing the 416 Rem mag.
But there may be hope yet as I've never tried Accurate 2230 in the 416 with 300 gr bullets.

quote:

For the curious: the Chrony reading was 3080 !!! Add 20 fps to that for correction to the muzzle and the answer would be 3100/6400 ft-lbs !!!

Obviously, there was something wrong with that!

Yes, that chronograph is reading too fast, at least sometimes. Try doing a double set up, shooting over two chronographs at the same time.
They should normally read within 30 fps of each other, mine regularly read within 10-15fps, and less.

416Tanzan,

The Oehler 35P has 3 sets of sky screens,
thus a "proof" of the test, as you describe.
I will use that to check the excellent results I got 07-18-2019
using a Chrony.

Rip ...

quote:

Originally posted by RIP:
416Tanzan,

The Oehler 35P has 3 sets of sky screens,
thus a "proof" of the test, as you describe.
I will use that to check the excellent results I got 07-18-2019
using a Chrony.


Rip ...

Yes, my double Chrono setups are in fact a poor-man's Oehler.

There is a lot that can be done in the hunting world with a little ingenuity and common parts. For example, almost 40 years ago in Africa I went "338" because I was a meat hunter and the 338's were available in standard models of common manufacturers at about 70% of the safari-priced 375's. At the time, the Nosler partitions capped at .338", too. The 375 Ruger has changed that, of course, and most every kind of bullet is available, but now Ruger has been slowly raising prices on their great deal.

You are doing something similar by "Creedmooring//Norma-ing" the 458 into a real 458 magnum. Chapeau. Kudos.
My inclination to off-the-shelf 416Rugers does not detract from my appreciation of 458WMs.

And "a poor-man's Oehler" reminds me of the 270 I just ordered for my Lady. The 270 is truly a poor man's magnum, pretty much duplicating the huntability of 7mRM with less expensive components and a lighter carry and lighter recoil. It was fun re-thinking everything: the "sexy" 6.5CM just doesn't have the capacity despite the great 8" twists, and for LeftHand models we couldn't go with attractive Kimbers or with inexpensive entry models but gravitated to Tikka, again. However, Tikka uses the same action for short or long cartridges so there was no weight advantage in skimping on case capacity. Voilà--the 270 literally rocked, and we've ordered another. (I toyed with a 7-08, knocking off the bolt stops and long-seating for 280 ballistics, but that was too much work and finesse for my limited time and windows for load development. If we want over-.300SD in the future we can always re-barrel a .277"with 7"-twist .277 and HammerHunter 168grainers, .620BC. But 10" is adequate for all-around 270 loads and the great bullets available. It is, afterall, only a small bore and we hunt under 400 yards.)

A lot can be done with common parts and a desire to hunt well.

416Tanzan,

Excellent support of THE MISSION, thanks.
The .458 WIN is EVERY MAN'S MAGNUM, the big game rifle that did more for Safari Hunting than P. H. Capstick.
And the .458 WIN did it without resorting to BS!

After 1956, any working stiff could go well armed to Africa, ready for anything he could dream of hunting.
It is the one best "re-creational" rifle extant for nostalgic "re-creation" of the entire evolution of sporting rifles over the last two centuries.
From old BPCR equivalent, or less, to full Nitro Express, and beyond.
Plink or plow as desired.
Tinkering with it as a wildcat makes it capable of much more than its excellent, original design parameters.
Even when SAAMI restricted, it has always been more than capable, all that anyone who can shoot would need, when the factory ammo was not sabotaged.
Maybe the rifle and ammo got too "cheap" at some point. The ship ran aground.
Then the rats abandoned ship. The ship has emptied its bilge and floated, and the .458 WIN sails on, better than ever,
more than enough gun.
With the proper bullet and a .458 WIN, one can move the planet, like Archimedes and his lever.

Rip ...

I think the following three loads are all near the same pressure (about 55,000 psi),
stepping down by reducing the powder charge by 3.0 grains of AA-2460 (75.0, 72.0, 69.0)
and reducing the COL by 0.125" and then 0.135" more.



5 shots for each load were chronographed at 5-yards.
Same bullet for each load, 543-gr FNGC sized to 0.461" over two coats of Harbor Freight Red.
Hornady brass case 2.500" trim.
F-215 primer.
81*F.
3 shots on paper for group at 50 yards showed an interesting progression.
Then two more shots with each load went through the Chrony and into the dirt, so as not to confuse my patterns.

3.340" COL with 69.0 grains AA-2460, 5-yard instrumental velocities, fps:
2125
2134
2124
2134
2136
Mean of 5 = 2130.6 fps
ES of 5 = 12 fps
St.dev. of 5 = 5.7 fps


3.475" COL with 72.0 grains AA-2460, 5-yard instrumental velocities, fps:
2190
2187
2190
2190
2191
Mean of 5 = 2189.6 fps
ES of 5 = 4 fps
St.dev. of 5 = 1.6 fps



3.600" COL with 75.0 grains AA-2460, 5-yard instrumental velocities, fps:
2247
2241
2242
2245
2252
Mean of 5 = 2245.4 fps
ES of 5 = 11 fps
St.dev. of 5 = 4.4 fps



The Oehler 35P and the Alpha Model Shooting Chrony are the only chronographs that I have not shot to pieces or lost.

Rip ...

The interesting 50-yard patterns:



As velocity, COL, and powder charge increased,
with pressure close to constant,
POI moved from left to right and upward.

Rip ...

This 544-grain cast bullet is similar in length and shape to the Hornady "500-grainers."
BC = SD/i
The Hornady-claimed BC for both DGX and DGS is 0.295, G1.
I am using 0.300 as an estimate for the BC of this cast bullet.

The 5-yard correction to MV is +13 fps.
69.0 grains/3.340" COL MV = 2144 fps
72.0 grains/3.475" COL MV = 2203 fps
75.0 grains/3.600" COL MV = 2258 fps

Occasionally, irregularities of the paint on the nose of the bullets will cause the 3.600" COL loads to jam the leade on chambering.
I fire them anyway.
Yes, the end of the .458 WIN throat can be reached!
There is no way for this 3.600" COL .458 WIN load to be loaded into a SAAMI .458 Lott chamber without using a mallet to do it.

I am concentrating on the most trouble-free 3.475" COL for further testing:
That is about as long as can be loaded into a .458 Lott with this bullet. Pressures would be higher in the .458 Lott.
Lower pressure in the .458 WIN LongCOL.

So, if the 25" barrel velocity is 2200 fps with 543-gr FNGC,
the estimated 20" barrel velocity is 2141 fps.

I believe that the Hornady 500-grain DGX and DGS could be driven at close to 2300 fps in a 25" barrel if allowed a COL of 3.475".
20" barrel would likely be over 2200 fps for COL of 3.475".
And pressures would be lower than for a SAAMI .458 Lott at same velocity and barrel length.

Western Powders data for a 24"-barreled .458 Winchester Magnum, SAAMI restricted, no powder compression:




Rip ...