Hot Load - The Book Can Be Right!

R

RC20

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I got loads crossed in the book, I found it interesting in that its the first time in all my re-loading there was an issue.

The load really was slightly below max for the grain of the bullet, and one that was slightly over.

First rounds had indications of pressure with the bolt just a tad sticky, primers were slightly cratered and flattened.

I have a Hornady Manual I keep with my target box, cross checked, hmmm, I see where I went wrong, we are on the edge but certainly not over.

As I knew where I was and I have a good modern gun, I tried the ones a few tenth of a grain over. Yep, worse, one primer blew out, more sticky, more crater, flatter, faint ejector marks.

End of shooting those, the rest got pulled.

For that gun and that powder, not only did they mean it, it turned out to be too hot for even a bit below the maximum listed.

Continue to enforce the solid wisdom of not going to max, sneak up on it.

If you do and or wind up there, the indications are there to inform you of that and to pay attention.

I thought it was kind of cool, all the symptoms you would look for.

First for me, I don't push loads. Any I have did not do that.

Got me to buy the Hornady Flip Lever bullet puller and like it.
 
Words of wisdom and good advice. Never exceed published data.

That said... If you’ve been doing this for enough decades you do start having a more nuanced view. My books from the 1970s have powders that are no longer available and data for the ones that are well in excess of the modern ones for quite a few loadings.

The reason I rarely hot load, or load from the older data is that in 30+ years I’ve only ever found an accuracy node in one rifle above the published maximums. 99% of the time your not going to find a node at maximum pressure, and groups will open up even more beyond it. It’s been my experience that you’ll usually find one around 95% of the maximum. Sometimes it’s lower, but very rarely is it higher. If I am exploring the tops of the data I will move in 1gr increments and examine each piece of spent brass closely for signs, as you have described.

Don’t feel bad. I’ve loaded a hundred belted magnums with the wrong powder, and only realized it when I went to label them. I use a kenetic puller, so it took me quite a while to turn it all back into components.
 
I thought this was a great example, all the comments about conservative data. Very current book, very current powder and it was too hot a shade below the max.

My creep up is at most 1/2 grain increments. With what I was seeing I would have stopped if it was a full grain.

But I also thought it was neat it had all the indicators of too hot for that gun and case mfg and all I had to do was pay attention.

And a good lesson its not conservative. Also good to have more than one book for the highs. And in this case, even with the right weight (3 grins more actually) the book was optimistic for that particular load. I thought I was low and was on the edge and still a tad low but not over and it was too much even for the first load. Second one clearly over and the third one would have been even worse (.5 grain increments)

I only load for target shooting and I have been up at the top a few times, a bit over looking for an accuracy node.

As noted, anything good has been below the top.
 
I've only had that happen once, and I was sneaking up on it. I was loading for a 300 WSM and a max load of H4350 was right giving me exactly what the books said it should be with acceptable accuracy. Not great, but I could live with it.

But I kept reading that RL17 was just as accurate and 100 fps faster so I tried it. I'd been getting 2950 fps with 180's with H4350 and was still getting good accuracy and no problems with RL17 at that speed. I don't recall the exact charge weights, but I was still over 2 gr below max when suddenly I was getting pressure signs and the velocity was faster than expected.

I had loaded 3-4 rounds at differing powder charges and stopped before going any farther and pulled those loads. At the end of the day the RL17 gave me good accuracy and no problems as long as it was loaded to about the same speeds as H4350. But even though the loading manual said I had room for 2-3 gr more powder it wasn't safe in MY rifle.
 
Been there done that and under similar circumstances. Had to pull forty eight out of fifty 45 ACP rounds once. I bought that RCBS bullet puller and never regretted it.
 
Words of wisdom and good advice. Never exceed published data.
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So if you are seated long thereby reducing internal case pressure or have a large chamber even further reducing pressure such that the Max published load is actually in the middle of the range, you still shouldn't exceed it?

I exceed published maxes all the time, they are generally suggestions. I have a rifle where a middle of the road load, seated to the manuals specs, will blow out primers because it has a very tight chamber.

My competition .300 win mag load is about 5 grains over the published max, but the bullet is seated 1/3" longer than the manual and it is throated to be loaded that way.

manuals are fallible guides, not absolute laws. Starting low and working up is the key, where you finally end up with the load should be more about your own careful observations.....that is if you are interested in getting the best performance.

But I kept reading that RL17 was just as accurate and 100 fps faster so I tried it. I'd been getting 2950 fps with 180's with H4350 and was still getting good accuracy and no problems with RL17 at that speed. I don't recall the exact charge weights, but I was still over 2 gr below max when suddenly I was getting pressure signs and the velocity was faster than expected.
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Funny thing about pressure in rifle chambers. It increases fairly predictably up to a point, then it may spike up alarmingly quickly. You may be working up from 41-45 grains, see no pressure signs at 45 gr, none at 45.5, none at 46, then at 47, the primers dimple outward, there are extractor wipe marks, the case has scratches, and velocity over the chroney that was going up by maybe 25fps/0.5 gr all the sudden goes up 75 fps!

Again why you have to work up slowly.
 
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Yep.

A lot of this was my take that the books are conservative. Conservative depends on a lot of factors so be aware, one persons conservative is another mans overly hot load.
 
For some reason I can't seem to quite express how I feel though the above covers it.

If I snuck up on it and it was still good without any indicators, then I would consider creeping over max if there was a goal or a reason.

Maybe another way of putting it is that max load level is like the old maps

Here Be Dragons.

Now you can go there, but you really want to do it carefully and do the serious due diligence that area justifies in some spaces.

No it won't blow up with a bit of bolt stick (modern gun) but its sure telling you Dragons Lie Just Ahead and you could be dragon food if you keep pushing it.
 
I often can't get to max published loads . Sticky bolt is often my first sign . The one thing I've not worked out is often when I see these pressure signs I'm still well below the velocities I'd think I should have if pressures were really that high .
 
Don't follow my method. Warning. Etc. Etc. I have been reloading since data published was insane by today's standards. I have reloaded for well over 200 rifles. Max load has been my starting load for over 30 years in hunting rifles, not target rifles. I have only had unacceptable signs of pressure in one rifle. It was due to a manufacturer, who I won't name, having the chamber cut wrong, actually crooked. Not sure how they managed that. It would be hard to do.
 
I have never and will never start out at max powder charge. As most say, sneak up on it. My 223, when it had the first barrel and the factory chamber, let me load up close to max. The second barrel had a very tight chamber, which I did not ask for and the gunsmith didn’t tell me about. If I had been able to chamber rounds from loads for barrel 1, I would have been well above max for the second barrel and probably had serious pressure problems. The max with barrel two is much lower.

Sneak up on it. Be safe.
 
It really helps to have a very good grasp of internal ballistics. I do find many manuals are quite conservative in some aspects. For example, cast (lead) projectiles in pistol calibers. You often find max loads that are below the min loads for jacketed projectiles of same weight. The goal is to prevent leading. Well, yeah pure lead isn't a great projectile. Some of today's cast can be pushed just as hard as jacketed in non-magnum handgun cartridges. Even heavy for caliber .357 cast rounds can be pushed pretty hard. In these cases over max data is perfectly safe, and the worst case scenario is a little lead fouling.

Another example!e. 8mm Mauser in a capable gun (let's say a yugo 24/47). Most max loads listed are terrible, and honestly will result in subpar accuracy. Its been my experience that under loaded rounds usually aren't as accurate as rounds that are withing their designed pressure curve. Many published loads for this round list a max load that is honestly less than ehatmthe starting load should be. There is a reason for it (older rifles with .318 bores), but those reasons are almost unicorns in shooting circulation today.

Some manuals (looking at you Richard Lee) don't recognize large frame Ruger only loads for 45 colt.

Seating bullets longer gives you a fair amount of wiggle room. I have some 9mm hs6 loads that are bordering max, but are pretty mild because I can seat longer. OTOH, an example of seating longer was given for a 300 mag above... Be careful when relying on this with a bottleneck rifle cartridge. Seating longer (closer to lands) can actually cause more pressure, and your benefits of extra case capacity are apples/oranges when comparing a bottleneck to a straight walled round. I'm not saying Mississippi is flat out wrong, I'm just saying his rifle is likely an anomaly and don't try to repeat his load in your rifle because it could end bad.

In the end, time on the reloading bench and experience is your friend. You will know when you can push the envelope and when to back off. My parting comment is this; always start below max, preferably at least 5% below max, and work up. You may be able to safely exceed max. Or max load in that particular component combination with that rifle may be too hot. 5% below is almost a promise not to blow the gun in a couple of firings, yet you will know if you're pushing the envelope.
 
Seating bullets longer gives you a fair amount of wiggle room. I have some 9mm hs6 loads that are bordering max, but are pretty mild because I can seat longer. OTOH, an example of seating longer was given for a 300 mag above... Be careful when relying on this with a bottleneck rifle cartridge. Seating longer (closer to lands) can actually cause more pressure, and your benefits of extra case capacity are apples/oranges when comparing a bottleneck to a straight walled round. I'm not saying Mississippi is flat out wrong, I'm just saying his rifle is likely an anomaly and don't try to repeat his load in your rifle because it could end bad.
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I have made that point before. I'm actually 0.020 off the lands. If you move too far into the lands, at some point the start pressure increases. Essentially seating longer reduces pressure, then if you get out far enough, it increases again. It's a balancing act. And also this isn't a production rifle chamber or barrel.
Like I said, I also have a gun where a middle of the manual .308 load was piercing primers or they were dimpled outward....in other words way too hot.

My point was the people who throw out these absolutes of "never exceed published max" or "I never load to...insert comment here" like the manual is perfect in every situation, haven't done enough research. Unless you just want to stick with minimums for recoil reduction which is a valid reason....but also acknowledge that the published max is a guideline, not a firm celling.
 
Not to hi-jack this but I've had questions on hand gun loads . Unlike rifle loading where it seems I'm less likely to get to max charges . I always seem to be able to get to max charge and past when loading 9mm & 45acp . Which brings up my next question . So what constitutes +P or +P+ loads . This term does not seem to be used in rifle loads so what is the definition of +P ? Is it to mean over max published data or just higher velocities then normal for caliber and bullet weight ?

I mean if you're using a fast powder like Titegroup with 147gr 9mm your velocities will be much lower at SAAMI max pressure then if you use lets say Longshot . While also having the very little wiggle room of only .3gr using Titegroup .

Most would say 900 to 950fps with a 147gr 9mm is about all you're going to get but Longshot will get you over 1000fps while still being safe ???

Titegroup gets you to 930fps @ 27,500 CUP

Longshot gets you over 1000fps @ 33,800psi or very close to the 9mm +p max of 35,000psi

I'm not sure what 27,500 cup is in PSI so I'm not sure if that's in the +p area but the Longshot max load does seem to be a +p load

Generally speaking if you are at max charge but not over is that generally considered a +p load or do you need to go over max charge or pressures to enter into the +p , +P+ area ?

Does velocity have anything to do with it ?
 
So what constitutes +P or +P+ loads
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+P is clearly defined. It is going over max SAAMI pressure limits by no more than 10%. +P+ is not defined and is more of Elmer Keith territory.

Does velocity have anything to do with it ?
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No, it is based off of pressure only. Since internal ballistics and pressure can be a funny thing, you really can't safely make "+P" ammo unless you have a reliable way to measure pressure. Many experienced reloaders may make hot ammo that is likely +P because they have a good grasp and understand how far to safely go.

Unlike rifle loading where it seems I'm less likely to get to max charges . I always seem to be able to get to max charge and past when loading 9mm & 45acp .
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There are fewer pressure signs when loading straight-walled, lower pressure pistol cartridges. 9mm operates at around 35k psi (without looking it up), and 45acp at 21k psi. Meanwhile, .308 operates at 62k psi. Yes, almost triple of 45acp pressure and almost double that of 9mm pressure. It can operate at this pressure because of rifle vs handgun design (rifles rely on a mechanically locked breach, fully support the case, and surround the case with much more metal support than handguns). You see flattened primers and case stretch in rifle rounds as signs of overpressure. You do not see these same signs in pistol cartridges.

The most reliable layman pressure sign with a semi-auto straight walled pistol is how far your brass gets flung. Even that is kind of like reading tea leaves. Pistol overloading can be especially dangerous because increasing charge weight by just .2 grains with many powders in a 9mm cartridge can give you up to a 4-5% greater charge weight. Couple that with seating just a hundredth of an inch too deep and the results can be VERY bad. Internal pressure is not linear, also. A 4% overcharge in powder weight could possibly equal a 10%+ overpressure spike, depending on the characteristics of the powder.
 
And the final word on it, loose primer pockets.

I picked up some Lapua once that had that, useless (some was ok)

All the indicators.

First time I had that occur and they were not that much over, they are now test pieces for annealing!
 
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I bought 1k of once fired LC-14 308 case . 12% of them have blown out primer pockets . I can tell which ones will be bad based on the case flow into the ejector . Any that have that little circle bulb on the head the primer pockets are toast . Working now but will post pictures later .
 
Aren’t the case heads stretched/bloted when your primer pockets get loose ? This lot of LC-14 case are the first cases That required a small base die to chamber freely in my bolt guns . To put that in perspective I’m currently using LC-09 , 10 , 12 & 14 in 308 and LC-10,11,12,13,14,16 in 5.56 . The LC-14’s are the only cases that I’ve ever needed a small base die for . They are also the only once fired cases I’ve bought that showed ejector marks on the heads . Sometimes i see light extractor marks but never ejector .
 
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