Old IMR 4350 load from Speer and Hornady was VERY HOT

[Float Pilot]

I have a BUNCH of reloading books. Many of them older....

So there I was trying to see how fast I could get a 150 grain boat-tail to come out of my 300 Win Mag.

I pulled some 150 grain full metal jacketed bullets (boat-tails) from some old 30-06 ammo.

Then I looked thru every book I had and fopund two very hot loads for 4350. They did not say IMR or Hogdens in the old books....
One load was 78.4 grains and the otehr was 79 in and old Speer book.
Both those were about 4 grains more than any modern book. And for good reason.

I used Winchester virgin brass, Winchester Magnum primers and loaded them to 3.340 COL with a medium roll crimp.

I fired them from my Remington M-700 XCR tactical rifle with a 26 inch barrel.
The velocities were much faster than those listed in the old books.
I fired 10 shots. The top velocity was 3,612 and the bottom velocity was 3,580 fps. ... These babies were smoking right along......They shot a 1.1 inch group at 100 yards from sandbags. OK for pulled military FMJs.

The brass showed considerable pressure signs. Primer flow (cratering), very flat primers, some ejector marks on the case and lots of stretching...

So those guys who wrote those old books either loaded everything as hot as possible or maybe there were a couple mis-prints...

I will back it off a couple grains and try some premium boat-tails to see what happens.....

[Murphy]

Welcome to the realm of 80,000 psi handloading.

The loads were probably just fine with the older 4350 powder. How old was that book? All of the IMR 4350 is much different form the old military (Hodgdons, military surplus powder) and the new H4350 is also much different. The old stuff was slower and more like 4831 in burn rate.

I believe your pressure marks indicate 75,000 to 80,000 psi. I'd say new primers won't fit the pocket anymore. Isn't handloading exciting.

[BrownBear]

I will back it off a couple grains and try some premium boat-tails to see what happens.....

Sounds like a dandy idea, but I usually go at it backwards from what you did, start lower and work up rather than start at the top and work down. Saves a bunch on brass!

I'm being tongue-in-cheek there, but you're primed now to know that the older the manual the more suspect the data. Powder changes over time, as does the way the writing and testing is done. For heavens sake, stay clear of the top loads recommended by PO Ackley and even the earlier Hodgdon manuals. You'll find loads in both where no amount of trickling, cussing, stomping and shoving by friends and neighbors will ever get the recommended charge into the case. If you could shoot it safely after you did.

I've got manuals dating back to the 1920s which include a bunch of powders that haven't existed inhalf a century. But some wear the same numbers as powders you can buy today. I use those old manuals as references for obsolete calibers, but when using modern powders I steer way clear of their top loads, always starting at the bottom of their load lists and usually holding my breath when I fire them off the first time.

When something as basic as a lot change in powder or primers can spike pressures right through the roof, decades of changes in manufacturing methods and specs for "the same" powder are a setup for buying a set of replacement brass if you start with the top loads and work down. Odds are that you're going to be replacing the brass simply so you get a chance to work down after you've fired the top loads.

[Float Pilot]

Murphy

Speer number 8 from 1970
Speer number 6 from 1965
The old 1971 Hornady manual
Lyman number 45

The time before lawyers ruled the world...



It was only ten rounds of brass, and my goal was to see how fast I could make them go...
They certainly achieved that.....

Makes me wonder about all the super hot loads I did back in Highschool and College.
I never had a chronograph back then... just lots of brass, money and powder.
I remember blowing the bottom off the cases in my 375HH and my old 300 Win mag built on a 1903A3 action....
There is still a tiny piece of brass in my left eye from 1975 or so.....

[mauserboy]

Well, yeah!

No offense, but if you've already sustained physical damage from overloading, why the %$#$ are you still doing it? Sheesh!

[Jmurman]

My current Speer manual says that H4350 max load is 76 with a velocity of 3219...this is a compressed load too. The IMR 4350 is listed as max load of 73 with 3091 fps MV

Sounds like you reached well beyond max pressure

[Float Pilot]

Jmurman:

There are all sorts of variations in charges. Some that are fairly low claim to be compressed loads.
This depends on the brass brand and bullet (ie boat-tail, partition or flat base.)

For example:

.............................IMR 4350................ H4350
Hornady #7............. 72.0..................N/A
Speer #14................ 73........................76
Lyman#48................ 76.......................n/a
Barnes#3.................. 74.......................75
Speer#9 ...................76........................N/A
Speer #8.................. 79.0.........................N/A
Hornady#2................ 78.9.....................N/A
Sierra#2 ..................76.2.......................N/A
Lyman#45................ 76.0.......................N/A
Hodgdon 08............... 58......................62 ..........And they claim compressed load.

I have been shooting 76 grains of IMR 4350 behind a 150 grain bullet, from Winchester brass, and it is not a compressed load. Nor does it show much in the way of pressure signs from my tight chambered M-700.
I shoot 180 grain accubonds faster than the Speer #14 manual shoots a 150 grain. And they are not particularly hot from my rifle.


mauserboy:

I have not blown a primer or split a case head off for over 37 years.
This load did not do anything along those lines. Oddly enough the brass was not even that swollen... However I have no reason to repeat this load now that I have seen what it will do in this particular rifle.
Hopefully all the other injuries from repeating certain activities will kill me off before an overload does... either that or I will be dying one day from nothing....

[Jmurman]

Float Pilot,

It's amazing at the differences between the various manuals and loads. I guess that sometimes to need to take a SWAG and go from there LOL

The Speer 8 and 9 has a three grain difference, wow, that's huge...unless the powder manufacturers have differing formulations on the various powders. I don't know if they do or not, do you have any thoughts on that?

I mean would 4350 change from year to year? Or any other powder for that matter?

[Float Pilot]

1.Like Murphy and Brownbear wrote, the older batches of powder may have had a slightly slower burn rate.

2. Plus the primers can make a difference. The newer magnum primers may be hotter. Plus I did an experiment this winter with various brands of primers and there was a significant difference between brands regarding velocity. In the old days they may not have used magnum primers at all, while developing some loads.

3. The temperature can make a HUGE difference in how much pressure the load developes. I am shooting loads at 5 degrees above zero. If we took that same load to Yemen on a 130 degree day we migh tblow something up..

4. Brass thickness can make a difference of a couple grains in volume. So Winchester brass may hold more than Federal or Remington.
I have some 6.8SPC brass from Silver State Armory (SSA) that uses a small rifle primer. It holds more powder than the Hornady or Remington brass which has a large rifle primer pocket. Virgin brass does not hold as much volume as brass that has been shot 6 times and trimmed. Tight fie formed brass that has only been neck sized may hold slightly more volume so it may generate less pressure with the same amount of powder... maybe...

5. A test rifle with lots of free-bore or a worn out bore has less pressure during firing. Even a faster twist rate can increase the pressure.
My Douglas 7x57 barrel has a tight chamber, no freebore and a good bore. I have another 7x57 with a shot-out bore as well. The shot out bore can shoot hot loaded rounds with almost no signs of pressure. But it shoots a group the size of a washing machine. So if the guys at Lyman used an old worn out rifle while working up loads for some caliber, that data stays published until they change to a different testing device. Meanwhikle the guys over at Speer might be using a new M77 Ruger or a test barrel.

6. Lawyers: Some guy sued even if he did not follow the correct proceedure. So everyone backs of the pressure levels as time goes on.
The lawyers become richer, then become politicians and eventually destroy the earth... Sorta like Godzilla..

[Jmurman]

... Sorta like Godzilla..

and the load for Godzilla?

I think that is one of the things i love about reloading...it's the variables and trying to adjust for each.

[Smitty of the North]

Float Pilot:
I love those old loading manuals. I have the Speer #5.

It tells the rifle or barrel that was used to obtain the data. So does the #10 and #12 The rifle used can be a huge factor.

I'm thinking, that the FMJ bullets were probably the biggest contributer to your results. ???

When you do something like that, you can fire the first shot with the gun placed in a tire, using a string on the trigger, and keep your distance. Then you know what you're getting into, after.

Anyway, now we're all alerted that older data, really can be DIFFERENT, so Thanks for posting this.

Smitty of the North

[bigswede358]

Just Wondering

what your 180 Accubond load is. I've been eyeing a Rem. 700 down at my local gun store, in a 300 winnie.

[Float Pilot]

I have it along with some others on reloaders nest.
I lapped the bore when I got this rifle and it really helped.
The 26 inch barrel helps build velocity, but it is a three sided bull barrel (three wide flat flutes that make the barrel semi-triangular) and the rifle is fairly heavy.

Load 5062 in caliber .300 Winchester Magnum
LoadID5062
BulletNosler Accubond
Bullet Weight180 grs
PowderIMR 4831
Powder Weight74.0 grs
PrimerCCI 250
Brass MakeWinchester
Barrel Length26 (inches)
C.O.L3.400 (inches)
Velocity3120 fps
Group 100 yds 0.45 (inches)
Submitted ByFloat Pilot
Gun Info Rem M-700 XCR Tactical, 1 in 10 twist
CommentGood balance of power and accuracy

[bigswede358]

Thanks

Thanks for the info Float Pilot. I wish money wasn't so tight right now, I'd go down and buy that 300 right now. I've never owned one, but its on my wish list. Have fun with those 150 screamers!

[300S&W]

I'll be finding out this summer how the burn rate of IMR4350 has changed over the past 20yrs. I developed a load using 150gr bullets and IMR4350 in my .300 in '88 and this past fall have finally run that lot of powder dry. Gonna be interesting to see what change will be needed in the new charge (+,-,none at all) to duplicate my old load.