Pressure Signs - Too Hot? (Pic Up)

[D_TROS]

Cal: 300 WM
Powder: 69.5 gr of IMR 4350
Bullet: 200 gr TSX Barnes
Velocity: 3050 fps

Concerns:
After doing load workups for 3 different bullets (BT, FB, and the TSX)I liked how the TSX was grouping (about 1.5" at 100 yds with my hunting rifle on a front rest) I shot 15 rounds in my Browning A-Bolt, 26" barrel and most of the brass showed no signs of too much presure. So I loaded 50 more rounds.

I had 3 cases that were silver (or nickle or something I am not sure) that I have had around for about 5 years that I considered my lucky cases cause they were shiny and I always got an elk with it. After shooting them, all three had a crack around the case about .5 inch up from the bottom of the case. One broke off during ejection and the casing remained in the chamber. The cracks are right about on the spot where the full length sizer stops on the way down on a sizing pass. None of the other 15 brass rounds showed any signs of cracking. And I never anneal my brass.

My concern is obviously loading them too hot and having something bad happen (explosion etc). So should I pull the bullets out of the other 50 rnds and reload or assume its ok cause the silver brass was probably overworked? Has anyone else experienced this problem?

I have never wanted to load a hunting rifle to its max just for the safety factor, and I plan to cut down to 68 grains of powder on ensuing loads. I have been loading for about 15 years and have never had this problem.

Thanks in advance and any opinions/facts will be appreciated,
DT

 

[5R Milspec]

Re: Pressure Signs - Too Hot?

first of all you are at the max end of that powder in the Hodgdon reloading book.and all three bullets will yield different pressures.and yes the nickel brass will become work hardened quicker.

now my question to you is just how many times has that brass been loaded?and annealing the brass will only affect the neck area of the brass.sounds to me that you have loaded the brass at max loads every time you have loaded them.but just guessing.

to really tell you a good answer we really need to know just how many times the brass has been loaded and if you Full Length all the time.even if you are seatting the dies up to just bump the shoulder back .002 of an inch.

 

[Clark]

Re: Pressure Signs - Too Hot?

It would not take high pressure to get that failure mode.
Hodgdon data is usually wimpy and not worth much.
High pressure takes a toll on the brass where it is thick, not where it is thin.
What could be happening is that the shoulder is getting pushed back with each reload and you have lost track of how many reloads on each case.
We would expect that failure mode some time, but we don't know when.

Worse yet, you could be pushing the shoulder back so far that you are head spacing off the belt.
The headspace on 300WM belt is erratic.
The 300WM SAAMI spec:
.220 - .008" for cartridge = .212 to .220"
.220 + .007" for chamber = .220 to .227"

My 300WM brass collection varies in belt thickness more that my 7mmRemMag, .264Mag, and 338WM collection, but that is probably because I have more of it. It is all made on the same H&H case head tooling.

My 300WM brass .210 - .217".
So if the rifle was at .227" and the brass at .212", and the FL sizer die moved the shoulder way back, the brass would stretch .015" with each firing. .002" or .004" of that might be elastic deformation, but the other .011 to .013" would be plastic deformation. You would be lucky to survive ONE firing cycle.

I have started chambering my rifles to fit the belts on the brass I have, but my belted magnum factory rifles come loose as a goose, per SAAMI specs.

 

[D_TROS]

Re: Pressure Signs - Too Hot?

I do full length size them every time.
This would be no more than the 8th time reloaded.

I dont keep track of the # of reloads for a couple reasons. One is my 4 brothers, my dad, and 2 family friends all shoot this cartridge when we go hunting. We keep the same brass for 5 years, reloading after practicing and hunting each season, throw away and buy new. We buy in 300 rds batches. Reason for not keeping track is that the brass, even if they were reloaded each time, they should be still workable. At least that is how it has been the last 10 or so years.

The issues came up this year as we jumped up from 180gr to 200 gr bullets for some more knockdown power and bigger hole = quicker death of large game. (I know some will say just place the shot well and this and that but this thread is not to argue the effectiveness of a bullet so save for another time).

I would of thought nothing of anything othere than the cracking silver cases except we just bought a chrono and when I saw the bullets going out on my longer barrel over 3000 fsp with a high of 3084, I got worried. My dads shorter barrel only got up to 2800 fps so not as much of a concern I dont think.

Thoughts?

Thanks again.
DT

 

[D_TROS]

Re: Pressure Signs - Too Hot?


I full length size each case because I am loading for 7 different chambers. I dont want any tight fits for some and a "just right" fit for others, I want the cartridge to fit all the rifles.

Also, my question is, even though it may be harder on the brass, is it dangerous to shoot the ammo I have reloaded already?

Thanks,
DT

 

[Clark]

Re: Pressure Signs - Too Hot?

I would not go elk hunting with unknown brass that may separate.

I would just shoot that stuff at the range.

I would hunt elk with a batch of known number of times fired, and how far the shoulder was pushed back.

Quickload thinks that 69.5 gr IMR4350 200gr TSX 26", 3.34" is 76kpsi 3069 fps

The 300 Win Mag is registered with SAAMI at 65 kpsi, but I have been elk hunting with what Quickload thinks is 74 kpsi.

That's ok, elk need a lot of killing to die.

 

[D_TROS]

Re: Pressure Signs - Too Hot?

will add pics this afternoon...

Can I measure to tell if the shoulder has been pushed back? How much push is bad?
How many reloads is considered too many?
Usually we would only toss brass early if there were any signs of wear...

 

[Greg Langelius *]

Re: Pressure Signs - Too Hot?

You had a case head separation. This is not usually a pressure issue, but a resizing issue.

It indicates the brass has been overworked in the area above the web. Typically this results from resizing issues; usually it means the dies are shortening the case excessively. When it fires, it stretches, and this back and forth wears the brass out.

You can test brass before loading by running a feeler down the case interior sidewall, checking for a groove that runs around the inside of the case somewhere within 1/2" of the interior bottom of the case. This shows where overworking during resizing has led to the brass thinning out in the area where the most stretching occurs. <span style="font-style: italic">Any</span> evidence of such a groove and that brass is toast.

I make my feelers by straightening out a paperclip and putting a right angle bend in about 1/8" from the end. The tip of the bend gets run up and down inside the lower portion of the case wall.

Sometimes a shiny ring appears on the case exterior, at a height even with the interior groove, but this is <span style="font-style: italic">not</span> a reliable indicator.

If you have any doubts about the safety or reliability of assembled ammo, the sane thing is to disassemble the ammo and check it so any doubts are resolved. Ammo that is in any way questionable should never be brought near the gun. It's just not worth it to take the chance.

I F/L resize my brass and generally replace it before I get to 8 loadings. Brass is cheaper than accidents.

To properly adjust the height of a F/L resizer die, back it off until it's obvious it's not shortening any cases. Then, take a fired case and see if it generates bolt drag on closure before you do anything with it.

If it doesn't, then adjust the die so it resizes the case neck most of the way down but does not resize all the way to the shoulder. This adjustment usually won't shorten the case at all, and eventually, subsequent firings will allow the case to stretch to where bolt drag on closure <span style="font-style: italic">should</span> occur.

OK, now that the case has an interference fit in the chamber, we adjust the F/L die down in small increments until we can suddenly detect a decrease in bolt drag. Ideally, we should still have small drag.

At this adjustment stage, the case is getting resized to the minimum degree (longest case/shoulder length) that will properly fit inside the chamber. This corresponds to the least brass working in the critical area above the web, and should forestall case head separation for the most reloading cycles.

The feeler test should be a regular part of your reloading process.

Loading for different rifles can be tricky. If some show bolt drag and some don't, you should establish die setups that provide some bolt drag for each rifle. This might entail using extra resizer dies sets if you are using setups like a Dillon Tool Head or a Lok-n-Load bushing. The point being that any conveniences and generalizations that compromise good handloading practices are probably really just another nail in somebody's coffin.

Greg

 

[D_TROS]

Re: Pressure Signs - Too Hot?

COAL: 3.331

Great Info thanks fellas. I was also going to go for the safe side and not chance either an accident OR a case possibly getting stuck in a chamber while hunting.

I read about that feeler idea somewhere once and cant wait to get home to try it. I was also curious what the case head separation was, now I know. I also like the idea of backing off the FL die. I never looked at it that way, and obviously I should have. Less expansion=more life and safer reloading.

Another question: why all the differences in the reloading books for max loads? the reason I went with 69 gr of 4350 is on e book said the max was 71gr and another said it was 67gr and my third book said it was 69gr. What reloading book do you guys like the best, think is most accurate/dependable for good loads? Speer? Nosler? Hornady? Sierrra?

Thasnks again.
DT

 

[Clark]

Re: Pressure Signs - Too Hot?

The TSX 200 gr is 1.497" long, and is longer than the other common 200 gr bullets, so it should be loaded with less powder.

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">
Wilson Case Gauge

* Mfr:L.E. WILSON, INC.
* Price:$26.95 - $44.95
*

The most important use of a cartridge case gage is for setting up 7/8""-14 press type full length resizing dies. A common error in reloading is to oversize your brass. Headspace of fired cases can quickly and accurately be measured using this tool and a pair of dial calipers. REGULAR STYLE This one piece gage will check overall length to indicate need for trimming, datum to head length to assure correct headspace and to prevent over sizing. Available for most popular rimless cases. ADJUSTABLE STYLE For belted mags. While the belt provides support for poper headspace, the ife of the case will drastically shorten unless resizing is held to a minimum at the shoulder. The gages, which can be adjusted to be used with individual rifles of the same caliber, will enable the handloader to control the amount of resizing simply by measuring a fired case. Overall length can also be check with these gage. SPECIAL ORDER CASE GAGES ARE AVAILABLE---MEASURE CASE LENGTH ONLY </div></div>

http://www.sinclairintl.com/.aspx/sid=63...&mc_id=8000

If you must have universal ammo, you could collect all 7 rifles and measure which has the shortest chamber.

Just adjusting the sizer die into the press until it hits the shell holder results in short brass life.

 

[Greg Langelius *]

Re: Pressure Signs - Too Hot?

Published loads are 'rather more like guidelines than rules', as they say in the pirate world. Each gun has its own ideas about max loads, and the published max is where the writers sorta hedge their bets.

My views are that:

A) Max loads are rather more there as a warning, than as a recommendation; sorta like "...and beyond here, there be dragons". Believe it about them dragons.

B) Max loads are tough on a rifle, and often not the best approach. For target and hunting, I'd rather work up to the first accuracy node above min, and stop there. Usually this means less copper fouling, with its companion attribute, longer strings before accuracy degrades from copper fouling. Velocity is just a number; whatever it is, it's our wind skills that make the shot work. Modern bullets do their job, it's our job to ensure we don't ask too much of them.

c) If you don't pin your hopes on max loads, and leave them over there on that other table where you never sit anyway; they will never be an issue. Newbs probe the limits. After awhile sensibility sets in, and they recognize that enough is plenty, and too much is really just it's own whole can of worms.

Greg

 

[AUJohn]

Re: Pressure Signs - Too Hot?

You are using mixed brass?
I would not push beyond published load data.
You have too many variables and it concerns me that some of the important basics have been missed.
When did you last check the brass?
Might be time to make a choice about adjustments as you have been quite lucky so far.
Check ALL the chambers against each other by buying a box of factory loads, shooting some in each gun and measuring and adjusting your die set to suit the largest one.
Throw away ALL your cases. Buy a new batch. Check them EVERY time if you want to keep mixing them. Yes, you might not have to check until the third load. I would not take the risk.
Log how many cycles each batch has had.
If I was you, loading for others, I would go back to the basics and make sure I was not forgetting anything. It's not just yourself who is at risk.


As was posted above, load for ACCURACY. It's ALL about accuracy. In your position I would simply aim for just under max so you have a margin for error. You do not have this at the moment and it's bad news

 

[D_TROS]

Re: Pressure Signs - Too Hot?

wow good info. thanks again. I agree changes need to be made and I just ordered some new brass. I would rather have a tight fitting round then a lose one to keep the bullet deformation to a minimum.

What reloading book do you guys think has the best ammo load information?

I was browsing the book section at Sportsmans and lookin at the books and I liked the Sierra books. I spose it would be best to buy the book for the make of bullet being shot...

Any thoughts?

Thanks,
DT

 

[D_TROS]

Re: Pressure Signs - Too Hot?

and good idea on the velocity. I am going to have to do some loading info before hunting. Starting low and working up to an accuracy node not only will save powder, it will also increase safety. I spose an elk wont really care if the bullet is going a hundo fps slower as long as we know the ballistics of the bullet at that velocity.

THanks again gentlemen..

 

[MitchAlsup]

Re: Pressure Signs - Too Hot?

See the first image at:

http://ar15barrels.com/prod/operation.shtml

for pressure signs.

 

[D_TROS]

Re: Pressure Signs - Too Hot?

Is it safe to assume (w/o making an ass outta u and me) that pressure signs on the brass will be visible (protruding primer, cracks, case neck separation, etc) will be visible long before there is any real danger of an action exploding? given you are within or near max loads?

Obviously nothing is a sure thing, but the signs of nearing too high of pressures are the typical "pressure signs"?

 

[Clark]

Re: Pressure Signs - Too Hot?

Stop with the pressure already.
You have stretched out brass.

 

[Greg Langelius *]

Re: Pressure Signs - Too Hot?

Gotta agree with this last. Quit sweating the pressures. As long as you don't go below published min for the bullet/powder and work up to the best accuracy upwardly adjacent, you should do excellent.

Since the bullet won't be screaming about at near max muzzle velocity, it makes reasonable sense not to demand the extreme long range peak performance, since terminal energy will be down somewhat.

It's my own view that trying to stretch the range on a hunting shot doesn't really prove anything that's compatible with conservative wisdom.

My approach is to prove I'm hungry and just get the job done. Finesse isn't any significant portion of my hunting approach. I set up as close to my ride as possible and try to keep the shots confined to an area where a clean kill won't result in a lengthy drag out.

Long and/or snap shots just increase the uncertainty, and I'd rather go home hungry than die of a heart attack dragging that long-running carcase out of the woods. I'm old, my ticker is rather a bit on the rusty side, and I need to constantly keep reminding myself to tame my self-expectations down from my leaner, younger, tougher days.

But the simple point of all that is just that it pays to keep it simple and easy no matter what your age or state of health. Folks who keep seeking challenge either haven't had enough challenges yet, or maybe they're just slow learners.

Greg

 

[D_TROS]

Re: Pressure Signs - Too Hot?

ok thanks. I was not trying to elongate the topic of this stretched brass anymore, just reloading and pressure signs in general as I want to reload competitively for benchrest now. I just recently (actually rifle just got in to my ffl) got a 6ppc and am about to start reloading for it. As I have never dealt with any pressure signs, and I have a lot more to learn about reloading, I was asking lots of questions. Guess I will have to start a new thread if anymore things pop up.

Thanks again for all ur help.

 

[Greg Langelius *]

Re: Pressure Signs - Too Hot?

Fine, meanwhile do the site search for evidences of pressure, so you can get some understanding of what to look for and what to pay attenton to.

Greg