S.E.E. loading data, need help

[jsn]

Richard Lee's 2nd Edition of Modern Reloading (2003) has a short section in Chapter 2, page 52, regarding possible excessive pressure caused from reduced charges of slow powders. The basics:

1) very slow powders with small caliber large capacity cases,
2) reduced charges by 25-35%
3) something bad happens that no one appears to be able to conclusively explain

The theories for 3):

1) wave pulses
2) bullet starts then stops, excessive pressure builds before it moves again
3) powder compresses against the shoulder, forming an obstruction
4) a small charge evenly distributed horizontally acts as a shaped charge and directs pressure to a small area on the top of the chamber

The Lee book uses reloading data from the powder companies.

[oldblinddog]

Richard Lee's 2nd Edition of Modern Reloading (2003) has a short section in Chapter 2, page 52, regarding possible excessive pressure caused from reduced charges of slow powders. The basics:

1) very slow powders with small caliber large capacity cases,
2) reduced charges by 25-35%
3) something bad happens that no one appears to be able to conclusively explain

This has been around and discussed as a "no-no" for as long as I have been reading about guns and reloading, which is about 50 years. As far as I can remember it has always been labeled as S.E.E. The warning not to reduce slow powders (IMR4831; IMR4350 were most common) more than 10% or so in a misguided effort to make what we call "mouse fart" loads has always been in the manuals. What more warning does one need?

1/28/17: There is an article in Handloder #306 (Feb. 2017) about reduced loads with the same warning that reduced (below published starting) loads of powders like IMR 4350 and slower are the cause of "pressure excursions" that can destroy the rifle.

[Larry Gibson]

Would appear with the departure of Mr Humble that this thread and the blown up M96 thread that led up to this one are dying. Yet some will come on and use the search function on the topic and still be able to read this and the other thread. Much of what Mr Humble has stated appears to have been gotten by him simply by researching the internet. While the internet can be useful we must remember that much information on the internet can also be false and misleading. This is simply because anyone can post just about anything on the internet, fact or fiction, without any liability. I don't wish to discuss the merits of that but am just pointing it out.

My point here is there are available information(s) from reliable sources on the topic of S.E.E. The technicians of powder manufacturers, reloading manuals and researches may not address it by that name but the premise of what causes an S.E.E. event is the same regardless of the name. There has been much research under controlled scientific testing taking place in the last 15 +/- or so years, especially since the laboratory testing as reported in the posted Hanloader article was made known. My point here is simply to offer a note of caution for those reading this and the other thread; don't rely on information posted by Mr Humble or anyone else who simply is surfing the net, can't find information and state it isn't so. There is information available and one should look at other sources than "on line". In this thread, as an example, Mr Humble posted this; .

"Could you share the details with us ? There is nothing unique about the 243 soooooo what works with it, should work for anything. In looking at the Hodgdon site 243 loading data vs my 10 year old Hodgdon book, I don't see any loads dropped, warnings etc. Nor has Hodgdon abruptly dropped any powders suitable for the 243. Looking forward to the information you have from Hodgdon."

He looks at one site (a well respected site), doesn't find anything related to the topic and assumes that to justify his position S.E.E. doesn't exist. Apparently Mr Humble did not research other reloading manuals that are readily available "off line". This information has been readily available for many years, many more that the 10 years Mr Humble only went back. I won't cite them all but just two examples from Hornady loading manuals.

In 1991 Hornady published the 4th Edition (a two volume set) of it's reloading manual. We may note the Hornady Reloading Manuals have been a staple to reloaders for many years prior to and to this day. The Hornady Reloading Manuals are one of the top manuals available containing scientifically tested reloading information. In Volume I of the 4th Edition on page 174 under the 243 Winchester cartridge we find this warning posted;

"Slow burning powders such as IMR4350 are not safe when loaded with reduced charges. Lighter charges of a slow burning propellant may cause unexpected high pressure, known as detonation. In some instances primers are blown, bolts stick, ore even stocks are splintered. At any rate, this detonation problem only exists with lower charges of slow burning powder and we do not recommend such use in the 243. Never use charges of slow burning powders lower than listed in our data."

Note the use of "detonation" as this was still the theory (60-70+ years old) of what was happening when an S.E.E. event occurred. The use of peizo-transducers, and more recently,strain gauge psi measuring came into use subsequent to the development of those theories. Transducers and strain gages are giving a much more complete picture of internal ballistics. With the advent of that type of measuring the cause of an S.E.E. event was first actually measured and reported in the Handloader article. Since the cause/reason for an S.E.E. event has became known we find the same warnings against the use of low charges of slow burning powder with the term "detonation" no longer used. It is now known smokeless propellant powders used for cartridges do not "detonate", they burn, albeit at a greater speed as pressures get extreme. We see this change in verbiage based on increased knowledge of proven scientific testing results are replacing the theories of old. Yet many like Mr Humble dredge up the old unproven theories regardless of what has been now proven.


In the 8th Edition of the Hornady Reloading Manual published 7 years ago under the 243 Winchester on page 247 we find the same basic warning with "detonation" no longer sued;

"Slow burning powders used with long bullets behave differently when loaded with reduced charges. These lighter charges may cause unexpectedly high pressure. On occasion primers are blown, bolts stick, or even stocks are splintered. This only occurs with lower charges of slow burning propellants and we definitely do not recommend such use in the 243 Winchester."

Obviously from the reports of S.E.E. type events reported in other cartridges the use of reduced charges of slow burning propellants can be as dangerous and the use of reduced charges of slow burning propellants should be cautioned against. Because a product such as a powder is misused by the consumer is not justification for the removal of said product by the manufacturer unless it is the product itself that is the problem. Mr Humble seems to think since Hodgdon hasn't apparently removed any powders that means, in his opinion, S.E.E. doesn't exist. We have to question just how would Mr Humble know if anything was deleted by just looking at Hodgdon's site is beyond me?

None the less I am providing this information hopefully to educate any readers of this thread that the problem of S.E.E., or whatever it is referenced as is very real and is well known in the industry even if they use another name or terminology for it. Just a cautionary word to the wise......

Larry Gibson

[Mr Humble]

As there have been complaints filed about me, I will no longer be posting on this subject.
Anyone who wants to speak further, please PM me. Thanks!

[Silvercreek Farmer]

Dang, I came here to see a blown up rifle....

[44man]

In our case with the Swedes, we had no gun damage other then a hard bolt lift and ruined brass. We are still shooting the rifles. Inspection showed nothing wrong. We both were shooting just under max loads of 4831. Seating to the proper depth stopped problems.
We did, however change to Varget and I have been down to .431" at 100 yards.
True you should never download slow powders but what happens? Pressure excursions of course but WHY? Does airspace force the powder against the bullet with the primer and move the bullet into a bore obstruction? Exact thing we seen in the .454 with powder packed in the bore behind a stuck boolit and barely discolored. What could happen if the powder did light? Starting loads of 296 with a wrong primer.
We will never know.
I do know the bullet must be held and air space reduced.
What happens in a rifle when you use an "M" die to reduce tension for the sake of seating easier? Lots of things I won't speculate on.

[Mr Humble]

"M" dies are ease seating not to reduce neck tension. Nobody uses M dies with jacketed bullets. As cast boolits are at minimum 2 thou over jacketed bullet diameter, they can shave if shoved in a case sized for jacketed bullets. A cast boolit of the right diameter will have proper tension when seated in an M die expanded case. Used M dies going back to the ones for my TruLine Junior. Never a problem.

[Larry Gibson]

Everyone who loads any straight walled case (mostly handgun cartridges and some tapered rifle cartridges) uses an "M-die" with cast or jacketed bullets. The M-die is referred to as an "expansion die" in most cases but the use is exactly the same regardless of the name. Also with some cases having very thin necks the use of an M-die is very beneficial in reducing scrunched necks when seating jacketed bullets. The 22 Hornet, 25-20 WCF and 45-70 specifically come to mind as I use an M-die with those when seating cast and jacketed bullets......haven't scrunched a case neck since I began using the M-die.

Larry Gibson

[Mr Humble]

An M die does not enlarge the neck diameter beyond what is correct. The top part of the M die mandrel bells the case mouth to ease bullet seating. If the belling portion of the mandrel does not touch the case, the neck tension is unchanged. The only reason to use an M die with jacketed bullets is to avoid neck collapse in thin neck wall cases like the 25-20, 32-20, 38-40 and 44-40 by belling the neck. As lead boolits are generally larger than the jacketed one for a given cartridge, the M die is used to open (bell) the neck to facilitate seating. Properly designed dies matched with properly designed jacketed bullets obviates the need to use an M die. I can seat a properly designed jacketed bullet in any straight wall case prepared with my quality dies w/o the use of an M die.

This is an example of a properly designed jacketed bullet that will easily seat w/o belling the neck. It's all about the base.

http://www.midwayusa.com/product/380...nose-box-of-50

[44man]

I have never had a problem with cast and have loaded for about everything. I shoot only cast from my 30-30 now and all I needed was a flare tool I made from an old RCBS die.
I never tried an "M" die so if it just flares--OK.
Never had a problem with 25-20, .35, .348, .308, 30-06, 30-30 or any straight wall case even with over size boolits. Just a tad of flare. I have never shaved lead.
I don't trust some dimensions of dies. RCBS never made a .44 load that shot like I want.
I bought a Lyman neck die for my 45-70 and a .460" boolit falls in. Not a worry with a BPCR but I would never use it with smokeless.
RCBS had the wrong dimension expander for the .45 Colt at one time until a gun writer complained. They changed it but I don't know if it is still fixed.

[Mr Humble]

That's why I buy Redding.

[Paul5388]

"But why this horrible disaster with 3 grains charge of powder in a strong .308 Winchester rifle ? This "homeopatic" load is, when it burns by normal deflargration, unable to propel even a 100 grainer half-jacketed Speer "Plinker" bullet through the rifle bore (unless bullet or bore is lubricated). How it is able to wreck the receiver of a rifle ? Or squeeze the case head through narrow extractor and ejector slots towards the face of shooter as the almost dust-sized splinters ?"

Because the mixture of flammable and oxidating gasses is already in GASEOUS form of existence, COMPRESSED and PRE-HEATED until the blazing-up temperature. Powder burns like firewood. Gas mixture burns like mixture of fuel vapor and air in the cylinder of internal-combustion Otto engine - when the fuel has too low Octane Value for the compression ratio of that engine, and the fuel-air mixture is blazed by a compression (whole charge at a time); not from the spark of a plug." http://guns.connect.fi/gow/QA6.html Found in answer to "SUPUTIN Loads for Intermediate Russian cartridge & The Mechanism and Chemistry of Secondary Explosion Effect"

[Paul5388]

On the computer that just blew up, I had documentation on RWS blowing up (SEE) .243s with N205. I'll see if I can retrieve it.

[EDG]

Nah
You use an M die because that is what came in the die set. It provides easier bullet seating regardless of the type of bullet being seated.
Sure you can seat a jacketed bullet without an M die. You can also seat a cast bullet without an M die. The base of the bullet matters not if the right die is used.
Apparently you have never used Redding 40-65 dies because they don't do much of anything right compared to Lyman or RCBS Cowboy dies.

An M die does not enlarge the neck diameter beyond what is correct. The top part of the M die mandrel bells the case mouth to ease bullet seating. If the belling portion of the mandrel does not touch the case, the neck tension is unchanged. The only reason to use an M die with jacketed bullets is to avoid neck collapse in thin neck wall cases like the 25-20, 32-20, 38-40 and 44-40 by belling the neck. As lead boolits are generally larger than the jacketed one for a given cartridge, the M die is used to open (bell) the neck to facilitate seating. Properly designed dies matched with properly designed jacketed bullets obviates the need to use an M die. I can seat a properly designed jacketed bullet in any straight wall case prepared with my quality dies w/o the use of an M die.

This is an example of a properly designed jacketed bullet that will easily seat w/o belling the neck. It's all about the base.

http://www.midwayusa.com/product/380...nose-box-of-50

[Larry Gibson]

paul5388

Interesting write up but what the author fails to comprehend in his "SUPUTIN Loads for Intermediate Russian cartridge & The Mechanism and Chemistry of Secondary Explosion Effect" with regards to the question posed; "But why this horrible disaster with 3 grains charge of powder in a strong .308 Winchester rifle?" is that 3 gr of any powder from Bullseye up through 5010 or whatever lacks the potential energy in a .308W cartridge to destroy any rifle. It doesn't matter how anyone theorizes, day dreams, has wishful thinking or comes up with wood burning or fuel vapor high or low octane internal combustion engines or what ever there just isn't enough energy in 3 gr of powder to cause the damage associated with it regardless of whether the powder burns, ignites of detonates.........The energy just isn't there and no amount of hallucination will make it be there.

Larry Gibson

[huntnman]

Maybe its on the nuclear level. Does a S.E.E. produce a mushroom cloud? (purple font, not smart enough to know how.) I've never seen one, hope I never will. I'll stick close to the books, just in case.
Greg<huntnman

[tomme boy]

This is what I use for a neck expanding die. Factories use something very similar to load their ammo. You can get a few sizes to size your neck exactly the size you want. It helps to hold the bullet and your seating die will close the bell when seating the bullet.

https://www.amazon.com/RCBS-Neck-Exp.../dp/B000N8N3Y4

[EDG]

I use Track of the Wolf expanders made to fit a Lee expander die. These work well for even soft 10 Brinell cast bullets

https://www.trackofthewolf.com/Searc...ch=expander%20

Buffalo also makes high quality BPCR and cast bullet expanders.

http://www.buffaloarms.com/custom_ex...s_pr-4035.aspx

[Paul5388]

Larry, I suppose it would be necessary to understand the effects of small quantities of materials in various situations. Fat Man, used on 9 Aug 1945, only utilized 14 pounds of material to produce the desired effect. Little Boy used 140 pounds of material to do a similar feat on 6 Aug 1945.

"Rifle powders are hard or almost impossible to ignite (because of deterrent coating), if the "loading density" of them is too low: If the powder space of a cartridge is half-full, 1/3-full or 25 % full. In one well-known instance the powder space of a .243 Winchester case was 85 % full of very slow-burning NORMA MRP powder but topped with 80 grains bullet. S.E. Effect wrecked a strong Universal Receiver and broke the Pietzo-electric Transducer (able to stand ten thousands atmospheres of peak pressure !). Test was repeated with another Universal Receiver and pressure test-barrel: Again "KA-BOOM !" Universal Receiver was ruined and the Transducer broken once again.

It was a rare event, when S.E.E. was REproduced purposely. It happened in West-Germany in the late 1960s or early 1970s. Whole story is told on a book: "Handbuch für den Wiederlader" by Dr. K.D. MEYER. This load of NORMA MRP was and is completely safe, if it is topped with 90 gr or 100 grains bullet. The pressure reading 10 000 atmospheres is just a tip of an iceberg: PAUL VIEILLE (a French inventor of smokeless single-base powder) knew about 110 years ago that the "wave pressure peak" of detonating smokeless powder may reach ca. 100 000 atmospheres. I know two instances (both in Finland) when a charge THREE (3) grains of shotshell powder behind a jacketed bullet (8 grams) was able to wreck a receiver of .308 Winchester rifle." I had a copy of "Handbuch für den Wiederlader" and had the appropriate section translated to verify the quoted portion of P.T.'s article, however I did miss remember the powder used.

[Larry Gibson]

paul5388

Are you seriously suggesting a nuclear reaction can take place?

Let me reiterate; "3 gr of any powder from Bullseye up through 5010 or whatever lacks the potential energy in a .308W cartridge to destroy any rifle. It doesn't matter how anyone theorizes, day dreams, has wishful thinking or comes up with wood burning or fuel vapor high or low octane internal combustion engines or what ever there just isn't enough energy in 3 gr of powder to cause the damage associated with it regardless of whether the powder burns, ignites of detonates.........The energy potential just isn't there and no amount of hallucination will make it be there."

I am well aware of the Meyer report along with other factual reports that give us an understanding of what S.E.E. really is and what causes it. 3 gr of any progressive powder in a .308W cartridge will not have sufficient potential energy to damage the rifle. Even if the bullet sticks in the throat the cartridge case and action will retain the psi generated as it doesn't exceed the MAP for that cartridge let alone the psi required to rupture the case or damage the action.

A given amount of material contains only so much energy potential (that is even the case with nuclear materials) and 3 gr of any progressive smokeless powder does not have the potential energy, regardless of how it is ignited or how it burns to release more energy. I measure pressures and have measured the psi's of many reduced loads. I have attempted to measure the psi of my own 3.2 gr load of Bullseye in the .308W under 90 - 118 gr cast bullets numerous times. I get no psi measurement because the psi generated is less than the 7,000 +/-psi needed to expand the case to apply pressure on the barrel and the additional 2,000 +/- psi needed to "strain" the barrel to get a measurement. The necks of said cases many times does not even expand. The energy potential just isn't there. The same load under a 100 gr HJ bullet will many times stick the bullet in the bore as quoted. The gas then escapes around the case and chamber wall causing no damage. A couple times the well fire formed cases did expand and the gas escaped when the bolt was opened (no the bolt did not fly back at all, let alone violently). Even with the bullet stuck there still was not sufficient psi to measure (that would be more than 9,000 +/- psi).


Wow, a nuclear reaction from just 3 gr of progressive powder in a .308W......whodda thunk.........man if the Iranians get ahold of that info.......gotta go, DHS SWAT teams are fixing to break in my door.....you'd better look outside as they obviously know who's got "the secret".........

Larry Gibson