safety reminder for journalists … um, I mean reloaders
S**T happens. Don’t let it happen to you. Pay attention.
on 02/26/2008 at 10:51 AM
Every reloader’s nightmare.
I’ve been reloading since 1971 and I still have all my fingers and they’re all where they’re supposed to be. Thank you, Lord!
I have made a couple of errors that might have been tragic, but they weren’t and I’ve learned.
Shame about that rifle, those are nice rifles. I’m really sorry about the hand; it was probably a nice hand, too.
On a technical note, do we know where the pressure graph originated?
"do we know where the pressure graph originated?”
Yes, I built it. It’s from the QuickLoad internal ballistics program, the only software package on the market that lets you work up loads on your computer before going near the reloading bench. Used in conjunction with the RSI pressure trace tool it is the only really safe way an experimental reloader can develop loads that are not in the loading manuals. QuickLoad isn’t perfect, but it’s pretty close. Close enough to get you in the ballpark, at which point the RSI tool allows you to custom tailor the load to your firearm. Combine these tools with that barrel harmonics theory and that Optimum Charge Weight theory, and you can develop powerful and accurate ammunition without having to shoot and shoot and shoot to figure out what works.
Wow.
Neat stuff. I just have one remaining question that’s been vexing me for years. About fifteen years ago, I built a Swedish Mauser with a 28” barrel into a very nice long range hunting/target rifle. The load I chose was the starting load from the RCBS manual; 140gr Sierra Match King & IMR4831, with the longest overall length I could get to stay in the brass.
It worked beautifully. Every group shot with it was .75 MOA or less. Pressure was mild to say the least. Years later, I decided I wanted a handier rifle with a more normal length barrel, so I bought a surplus Swedish carbine. Taking it to the range for its basic check out produced a scary result using my pet low pressure load from years ago. It showed severe high pressure signs. Very stiff bolt lift (whacked it with the heel of my hand) and the primer was severely flattened with cratering around the firing pin. Using factory 6.5 ammo showed no problems at all, but 100 yard groups ran around 2 to 3 inches.
Btw, that 2 to 3 inch group was also typical of my first Swede with factory ammo.
Does anyone have a clue what happened? One guy said I should increase the charge weight and gave an example of how well it had worked for him. He said he got it from one of Ackley’s books. If he was wrong, I don’t want to find out how good a steel the Swedes used.
And that deceptively simple question, “What if I’m wrong?”, marks the profound difference between someone who doesn’t have to replace his rifle and someone who has to replace not only his rifle, but his hand.
I call it evolution in action, myself. The bad news is that the guy who didn’t use the paranoia-level caution appropriate to someone working with explosives *could* sue the manufacturer of the rifle, the manufacturer of the powder, and probably the NRA. Since US clothes iron manufacturers are now putting labels on their irons telling you not to iron your clothes *while you are wearing them*, I don’t hold out much hope that his self-mutilation would be considered his own damn fault, either.
The good news is that, being a gunny, he’s likely to think well of the concepts of self-reliance and personal responsibility and never file suit in the first place. To some of us, the humiliation of publicly declaring oneself to be a helpless whiner would be worse than losing the hand.
And yes, I know that gunpowder technically does not “explode”. Neither do matches, but you can still turn a car into a wreck with a match head bomb. And the same “paranoia-level caution” is appropriate when building one.
That is some serious pressure close to 90,000 psi if I read that chart correctly. I always err on the side of caution when reloading.
The comments from GOF about ironing clothes whilst wearing them are quite depressing really. On a similar note I bought a big bottle of aspirins last time I was on holiday in the US. The British nanny state will only allow the public to buy something like 16 at a time (I shit you not) because they don’t want people to overdose on them. Pathetic isn’t it? Anyway the bottle of 300 aspirins I bought in the US has a picture of an aspirin on the label which says “actual size.” Fine you’re thinking. However, the bottle is transparent?. So why do you need an illustration of the size when you can see the bloody things? Am I missing something here?
Dr. Jeff, yes, I know the nature of your problem.
In short, all rifles (all firearms) are unique. Whereas all 6.5 Swedes run in the same pressure levels, that does not mean all are identical. The bore diameters will differ (in the +/-.000x levels) and in smoothness or frictional nature and so forth. The chambers will vary by some fraction of a percentage and therefore have different volumes. All this combines to make a difference in total.
I like the 6.5 Swede. To no one’s great surprize, mine respond well to heavier bullets (140 grains and up) and slow powder. I prefer H4831, but IMR4831 is acceptable. I have the short barreled version, so I tend to go for the 160 grain bullets, but I digress.
I’d be willing to bet your load that worked well in your ‘old’ rifle was at the top end of the loading list. I say that with confidence because historically, those are the ones that work best. However, when you used that load in your ‘new’ rifle, you got over pressure signs. That’s because all those variables I mentioned added up and in one direction only. (Sometimes the ‘new’ rifle shoots cooler.) Just out of curiousity, did you change lots of powder? Modern powder is very consistent, lot to lot, but still there are small variations.
You know the basic rule: Always start at the bottom and work up. You know have a striking and memorable illustration of that axiom. Happily, without serious consequence.
The dumbest thing I ever did was to substitute H4831SC for H4831. The rifle held easily enough, it’s a 1917 Eddystone. But the primers leaked a bit and came out very, very easily. As best I can calculate, somewhere in the 80,000 psi range. Only took once to teach me that trick.
Archie, all your points are good, but I’ve already looked at them. On the side, I’ve never understood why the 6.5 never became more popular. It’s a remarkable round.
1) Same batch of powder, primers and bullets. In fact they were all from the same reloading session. Not even the variance of resetting the powder measure.
2) The load is actually the starting load straight from the RCBS manual. It’s very low pressure, but it does everything I want, so why burn more powder? Since it is a starting load, even if I’d goofed the powder measure by as much a 5% or 10%, the load should have been safe. I’ve had some people recommend a compressed load when using IMR4831.
3) The performance of the factory ammo is what really flummoxed me. I had some that was set to the same OAL length as my target loads and some that I’d left at the original factory length. There were no other changes. Both worked reasonably well in the carbine, if you’re willing to accept 2-3” groups. If the factory ammo had shown the same problems as the reloads, I’d feel a lot better.My original rifle groups about the same with factory ammo, it really likes those handloads. Groups with the handloads typicaly run from .38” to .75”. I’m sort of working on the theory that since the target loads were only neck sized (shoulder not pushed back)I could have gotten some sort of effect similar to having a short chamber, but I have no evidence to back that up. The bolt always closed easily with no hint of drag. Another possible idea is that the neck of the cartridge may have gone too far up the bore. Possible, but that still doesn’t account for the performance of the factory ammo. Anyway, this whole business has stumped me and a number of other people as well. I’m looking for any idea I can find, but almost all the sane ones, like yours, have been pretty much ruled out. Eventually, I’ll probably just get a barrel from Brownell’s and try to forget about the whole problem. I just don’t like having something like this where I can’t find an answer.
02/27/2008 at 03:12 PM
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