Exceeding max load reccomemdations?

[shibumiseeker]

I didn't say there were never any reasons to go over max, but in the case of a Desert Eagle that canon is really just a boy toy. You might be able to open carry it in places like Alaska or Montana, but if I was to use a handgun in brown bear country it wouldn't even be a handgun: it would be a rifle.

I'm not carrying a rifle or a shotgun when I am backpacking. Too much weight.

That being said you make a very valid point: sometimes you want more power. But as far as +P+ ammo goes SAAMI doesn't have a standard for it

That was my point. +P+ exists despite there not being a SAAMI standard for the simple fact that an ammunition that was designed around a certain pressure originally will have guns that are designed for that pressure. Either newer guns with better metallurgy come along like what happened with the 9mm and .38spl among a few, or a gun was designed to use a hotter load than SAAMI specs like the case of SMGs or my custom modified Glock20.

We're not in disagreement about the need for proceeding cautiously. I just disagreed with your assertion as to " why would you EVER need a load over max!" as there are good reasons to do so.

 

[Broom_jm]

There is only one way to safely EXCEED maximum listed loads: you get a quality chronograph and if the velocity that YOUR particular firearm produces is still below the FPS that the listed loads produced in the manual with the SELECTED POWDER it is okay to go over the load CAREFULLY! That is of course if you don't see any obvious pressure signs, but that seems to be an art I don't have an established skill in, and most loaders don't either (despite what you read or watch on YouTube). Also understand that the velocity the chrony meausures is not at the barrel you'll have to use a ballistics software program to estimate the muzzle velocity for a particular bullet (weight and BC are important). The chronograph is the best tool you can have as a handloader and they are far less expensive than say a completely destroyed weapon that needs to be replaced because you thought it could handle higher than listed max loads.

With all due respect, you stepped into a big pile of it...

Using the speed shown by a chronograph is NOT, EVER...a good way to determine the pressures being generated by your gun. This is 100% erroneous and I can't over-emphasize how important it is for folks to disregard your statement, in its entirety!

Powder specifications change. Barrel lengths vary from what was used in the reloading manual. Some barrels are tighter and some are looser, resulting in significant variations in velocity. Barrels can have different rates of twist than the one used in testing. The chronographs most handloaders have are NOT as precise as those used by professional ballisticians; yours may be slow. How far a chronograph is the from muzzle is critical, as are the weather conditions and placement of the sun screens.

Understand that the velocity reading you get from a chronograph is not indicative of anything related to the pressure in your gun. Get that idea out of your head, especially if you're trying to a ruined gun and dangerous situation. Chronographs, presuming you know how to set one up properly and that it is providing you with accurate readings, are useful for a few things, only:

1) They will help you determine the average speed of your load, allowing you to make certain calculations concerning trajectory and energy.

2) They help you determine the ES (extreme spread) and SD (standard deviation) in the velocity of your loads. This can be used to help define a more accurate long-range load.

Aside from those two things, chronographs are nice little toys. They are certainly not a requirement for a reloader, provided that one is prudent enough to avoid exceeding maximum charges. In short, good sir, your advice is ill-considered on both counts.

When people know what they're doing, and know what to look out for, it is possible to exceed a published load. Those folks do NOT use a chronograph to determine when they've reached a certain pressure threshold. Never have, never will.

 

[shibumiseeker]

Yes the pressure sensors are the most accurate way to estimate chamber pressure in a firearm but do you want to spend $500? Recreational Software, Inc.: PressureTrace & Accessories I think I would rather buy another gun for that cost. An F-1 shooting chrony is less than $100 on Midway USA

I haven't *yet* spent the money on a strain gauge, but I do enough testing that I've given it serious consideration, and I've used one with a friend on three occasions when we were doing some destructive testing.

When I first started they were well out of the price range of the average shooter. They are now in the ballpark of what I would consider part of any well-stocked load developer's toolkit.

 

[avboiler11]

I don't reload for pistol...but the very best loads in my 260 Remington are over "published max".

No sticky bolt, no pancaked primers, and no ejector swipe (okay, maybe occasional light swipe but no other pressure signs).

Then again, I had a MAJOR overpressure and blew a primer out on a load with W760 that was one full grain below max published charge due in no small part to that powder's temperature insensitivity. Knew I had a big problem when recoil felt like a 30-06 and I saw nearly 3200fps on the chronograph with a 123gr bullet.

Start low, work up, learn to read pressure signs and ALWAYS wear eye protection.

 

[dasprung]

Broom_jm you are absolutely right, not all chronographs are created equal but one of the number one things to consider in reloading is data. The more of it you have the better. If you don't use a chronograph then what do you use? Your superior knowledge of how much pressure your particular case, bullet, powder, primer, barrel and reciever can take? All the traditional high-pressure signs have proven unreliable, including bolt lift and measuring case heads. Modern rifles and brass can allow the bolt to be lifted easily even with roungs that test 70,000 PSI or more, and case head measurements can result in high pressure signs at much less than 60,000 PSI, due to differing hardness in brass. Yes there are "slow" and "fast" barrels but there are no "magically fast" barrels. A chronograph is a relatively easy and inexpensive tool to use, and there is a very strong correlation between velocity and pressure. If a chronograph is judged by you to be accurate enough to calculate the statistics of a "population of data" (i.e. X number of loaded rounds) than why isn't it accurate enough to estimate the pressures in a load based on the velocities it generates? Don't trust the chrony? But you did for the statistics earlier...whats going on?! If you shot a hand load of yours that had a chronographed (and averaged) higher than maximum velocity published in a reloading manual wouldn't you stop and think, "Ooo... maybe that was a bit much..." The beauty of taking what you see with a chronograph on the range from a "population" of data and comparing it to the data generated by companies like Hornady, Nosler, Sierra, etc. who have the sophisticated pressure reading gauges and chronographs they use to calculate their data that they publish (albeit with lawyers hovering overhead). They do the work for you, you just need to validate it by comparing your velocities to theirs, obviously taking into account the firearm and barrel length they used for testing.

 

[Yeah]

I can both read sign and I own the above linked Pressuretrace, and nearly all of my go to rifle loads are above the book. With modern rifles a pressure induced catastrophic failure due to anything other than barrel obstruction would take some serious doing.

But slap one of my loads in some old Mouser and set back lugs wouldn't be out of the question.

 

[Broom_jm]

Dasprung,

Yours is a common misconception that guys are more than willing to buy into, because it helps justify their purchase of a chronograph. They tell themselves they "need" a chronograph because it will help them keep their loads safe. That is pure rubbish.

Let's analyze the word, "chronograph". Chrono is a prefix pertaining to time and graph is the measurement thereof. A chronograph measures the time it takes for a bullet to pass from one electronic screen to another and uses that time as a means to calculate velocity. As interesting as that is, the chronograph does not do a single thing that tells you what pressure is occurring in your barrel.

The examples I could list are numerous. I already gave you 6 reasons why even fairly accurate velocity readings from a chronograph are not necessarily correlated to the pressure being generated in your gun. Here is another example: If you are 3 grains below max according to a recent reloading manual, but the bolt is very hard to open and you have very obvious flattening and cratering of the primer, do you really CARE what your chronograph reads? What if your speed machine says you're still 200fps under what you should be getting for a max load? Are you going to keep adding more powder or are you going to take a SERIOUS look at the recipe you're using?

See, you want the chronograph to tell you it's OK to add another grain of powder, because your bullets are not going as fast as the book load. You're trying to convince yourself that if your bullets aren't going as fast, it MUST BE because the pressure isn't as high as the book load was creating. You are assuming a direct, 1:1 correlation between pressure and velocity...such does not exist. There are so many reasons that your load might be slower, or faster, than what is published in a reloading manual. Trying to make your loads match those numbers is a fool's errand; plain n' simple.

Chronographs are for telling you how fast your bullets are going. If you don't trust your powers of discernment to determine if a given load recipe is over pressure in your gun, please do yourself a favor and leave the measurement of chamber pressures up to the professionals. Trust their work, since you don't believe the pressure signs they tell you to look for in the reloading manual. (Have you ever seen a reloading manual tell you to get a chronograph reading to verify pressures??)

Sometimes the best thing you can do, when you find yourself on the wrong end of a losing argument is to step back and really analyze what you think you know. This is one situation where you may be right 95 times out of 100, but those other 5 times you're putting yourself in harm's way. When the end result can be downright terminal, those are not good odds. Use a chronograph for what it was designed to do.

 

[dasprung]

Broom, it seems we just differ in opinion here. A chronograph does not give you a liscense to play with powder charges over max (if the charge is below listed max) it gives you just another tool (one of many the most important being your own two eyes and experience) to use when approaching close to or near max loads. I love my chronograph (especially with my rifles) as it allows me to calculate with a degree of certainty where the bullet will be at X number of yards. They are invaluable tools in that regard and anyone who shoots beyond 300-400 yards will appreciate the information they provide. I'm sorry if I "stepped in it"

 

[dasprung]

I know if you were a new reloader that just started and you saw the statement: "Just get a chronograph and trust it no matter what the brass or firearm is telling you" can be misleading. The reason we have pressure indicators in major bullet and powder manufacturers data is because we still have to look for OBVIOUS signs of pressure. These pressure signs can still be misleading and that is where the chronograph comes. Its used to analyze the shots you take that don't exhibit the high pressure you would expect to see from a high end load. If your 240 grain 44 mag bullets show a velocity over 2000+ FPS you should probably think of backing it down no matter what your cartridge, extraction, or primer pocket tells you.

 

[dasprung]

All things considered I still find that the best accuracy is still obtained close to or near the max listed load, not over. If Broom_jm is as experienced a reloader as I assume he is probably in agreement with me on this. Thats all. And Broom even though you may distrust chronographs it doesn't mean they are still not valuable tools. As I stated earlier more data (not less) is always better. :-)

 

[dasprung]

See, you want the chronograph to tell you it's OK to add another grain of powder, because your bullets are not going as fast as the book load. You're trying to convince yourself that if your bullets aren't going as fast, it MUST BE because the pressure isn't as high as the book load was creating. You are assuming a direct, 1:1 correlation between pressure and velocity...such does not exist.

Couldn't help myself. Broom_jm, doesn't a higher pressure produce more velocity to? Can you think of any modern studies that show that higher pressure occurs without an increase in velocity? Find me an example (besides an obvious barrel obstruction)? To say that a firearm will generate high pressure without a corresponding increase in velocity seems a fallacy.

 

[dasprung]

Once again this is assuming that the brass and firearm are not exhibiting OBVIOUS pressure signs.

 

[SSGSAD]

See, you want the chronograph to tell you it's OK to add another grain of powder, because your bullets are not going as fast as the book load. You're trying to convince yourself that if your bullets aren't going as fast, it MUST BE because the pressure isn't as high as the book load was creating. You are assuming a direct, 1:1 correlation between pressure and velocity...such does not exist.

Couldn't help myself. Broom_jm, doesn't a higher pressure produce more velocity to? Can you think of any modern studies that show that higher pressure occurs without an increase in velocity? Find me an example (besides an obvious barrel obstruction)? To say that a firearm will generate high pressure without a corresponding increase in velocity seems a fallacy.

Remember, that some, if not MOST reloading manuals, will tell you the firearm, they used to get the results, that they publish ... My Speer, tells on almost every caliber, and sometimes they use a "test barrel" I cannot think of the correct name, right now, but it seals better, and has higher pressure, because of no cylinder gap ... I am drawing a blank... sorry ..

 

[mac45]

All things considered I still find that the best accuracy is still obtained close to or near the max listed load, not over. If Broom_jm is as experienced a reloader as I assume he is probably in agreement with me on this. Thats all. And Broom even though you may distrust chronographs it doesn't mean they are still not valuable tools. As I stated earlier more data (not less) is always better. :-)

I'm gonna disagree that the best accuracy is obtained at max or near max loads. I have a couple rifles, and several handguns where the "sweet spot" is actually below the published starting load in some manuals. Got a few that like to go fast too. I have no doubt that whatever it is you're loading for likes to go fast as well. My only point is that every gun is different. If you start with the premiss that you need to go fast to be accurate, sooner or later you're gonna be disappointed.

 

[Tydeeh22]

whats amatter with running really hot loads? if he does it, i can do it right?

 

[Broom_jm]

Couldn't help myself. Broom_jm, doesn't a higher pressure produce more velocity to? Can you think of any modern studies that show that higher pressure occurs without an increase in velocity? Find me an example (besides an obvious barrel obstruction)? To say that a firearm will generate high pressure without a corresponding increase in velocity seems a fallacy.

Yes, higher pressure creates more velocity...right up until the point where your gun blows up and the pressure escapes at the breech. Then, you have less velocity. Although it won't be as much of a concern to you at that time.

You ask me to quote a study that shows higher pressures can't exist without an increase in velocity. Then, you add in 2 caveats yourself. What if a barrel is just really dirty? What if the load was published for a 1:12 barrel chambered in 223, but yours is a 1:7 barrel, meant for long and heavy bullets? Do you even understand how much of an impact that would make? What if you're loading for a 460S&W and the published data/velocity is from a pistol, but you've got a 20" Katahdin barrel for your Encore? Do you stop when your velocity matches the pistol data or do you follow the load recipe? What if the inverse was true and you were loading for a 15" Encore pistol in 243? Do you keep adding more powder until you get rifle velocity?? Dude, I could go on and on.

Do you know what QuickLoad is? Do you have a copy of it? Do you understand the relationship between cross-sectional bore area and the expansion ratio for a given cartridge? What about secondary pressure spikes in low-density rifle loads? In other words, are you qualified to make authoritative statements about the relationship between pressure and velocity? They DO correlate, but it is NOT 1:1! Do you understand that? If "X" pressure creates "Y" velocity, then X*1.1 does NOT equal Y*1.1 and you're nuts if you think it does. You aren't much wiser if you adjust your load to match the velocity published in a load book with what your chronograph is reading. Again, that is a fool's errand.

I've been reloading since I was 16 and I turned 41 last month. I reload for over 20 cartridges and half a dozen different shotshell recipes. Three of the rounds I reload for are true wildcats and two others are old or very obscure rounds. Data is scarce to non-existent for these rounds, so I have to know how to identify safe starting loads and pressure signs as I work my way up. Hint: The chronograph is not part of this process, in any way.

While I'm not a professional ballistician, I AM smart enough to listen to them. Your premise is flawed and not espoused by anyone but armchair reloading "experts" who don't understand the entire picture of what they're doing and what a chronograph measures. If it was wise to use a chronograph to help ascertain what pressures you are getting from a given load recipe, don't you think that would be listed in your reloading manuals?

 

[ghitch75]

when i was workin' up a load for my "Ruger only" 45 Colt load with 270gr Penn Thunder heads and was from a 7 1/2" Blackhawk.....got up to 27gr of 296 runnin' 1525fps and no signs of over pressure.....bumped charge to 27.2gr no sign of over pressure and still runnin; 1525fps.....jumped to 27.5gr flattin' primers and would hardly eject....but here's the kicker....speed drop to 1450fps!!!!.....i think the over pressure cause the bullet to swelled tighter in the bore jumpin' the pressure......so DON'T EVER THINK YOUR CHRONY WILL TELL YOU PRESSURES!!!!!!....read your cases!!!!

 

[dasprung]

This is my last post on this. I'll bow to your experience and give up trying to advocate the use of chronographs with an individuals better judgement on what pressure signs to look for. I tell you what I'll just throw it out. Good luck with your reloading Broom and thanks for "showing me the one true light"

 

[Broom_jm]

This is my last post on this. I'll bow to your experience and give up trying to advocate the use of chronographs with an individuals better judgement on what pressure signs to look for. I tell you what I'll just throw it out. Good luck with your reloading Broom and thanks for "showing me the one true light"

Think of me what you will...if my vociferous argument against using a chronograph as a means of gauging chamber pressure keeps you, or someone else, from getting hurt, I'm happy to be the bad guy.

 

[45fan]

when i was workin' up a load for my "Ruger only" 45 Colt load with 270gr Penn Thunder heads and was from a 7 1/2" Blackhawk.....got up to 27gr of 296 runnin' 1525fps and no signs of over pressure.....bumped charge to 27.2gr no sign of over pressure and still runnin; 1525fps.....jumped to 27.5gr flattin' primers and would hardly eject....but here's the kicker....speed drop to 1450fps!!!!.....i think the over pressure cause the bullet to swelled tighter in the bore jumpin' the pressure......so DON'T EVER THINK YOUR CHRONY WILL TELL YOU PRESSURES!!!!!!....read your cases!!!!

I think this is an example of where the Chronograph data, used in conjunction with the traditional over pressure signs and experience could have indicated that the load was getting a bit on the hot side. I do not have quite as many years involved as Jim, and I dont care to get into a "whos is bigger" argument, but the argument that bullet speed data is useless when working up a load is just ignorant. Different powders react differently under different pressures, such as indicated by ghitch's post. When pressure increased past a certain window, many powders will loose efficiency, and the gain in velocity will either stagnate, or drop off. If you are watching the other pressure signs, and incrementally upping your charge weight, if you come across a point when the load does not increase velocity over the last one tested, its a good chance that you are over pressure.

Its not just the bullet speed of the one load that is helpful, but the overall data, that should be compiled and studied to determine a little better idea of what is going on.