I have doubts, need input

[44man]

I have been thinking about case neck expansion in the chamber. Now I am not talking about rifle brass (or any caliber for that matter.) that fits too tight in a chamber and locks the bullet in front of tremendous pressure, this I understand perfectly.
I am talking about straight wall revolver brass, mostly, or even rifle brass that fits the chamber properly.
Just thinking about it, I picture the brass expanding in a rolling motion as the boolit moves foreward. I just can't see the whole neck of the case jumping open all at once. If this were true, case neck tension and the crimp would mean nothing at all.
Yet, everything I have ever read says the case mouth must open to release the bullet but the bullet is blocking the pressure from acting on the brass until it moves out of the way.
Sounds to me that this is much different then forcing the brass into the bullet so tight in the chamber that it can't move which increases pressure of course.
Then what about those dead soft boolits that expand in the case from pressure? Does this not force the brass into the chamber wall making it tighter?
What are your thoughts on this?
I foresee a good week of discussion with this post!

[felix]

Restate, please, contrasting the two views. ... felix

[Heavy]

Just a thought that the brass at the neck must roll to some extent. But the difference in the materials (lead vs brass) cause the lead to adhere to the brass. Case streach is in the neck area: not in the base as is the case with excessive head space.

[klausg]

I am in agreement with felix, I'm not too sure exactly what you're asking. FWIW, I feel that the brass must expand prior to bullet movement; that sufficient case neck tension is necessarry to allow time for the brass to expand to seal the chamber prior to bullet movement. Otherwise, the gas could leak between the brass & chamber wall causing @ least a smoked case. I do agree that the whole purpose of the crimp is to prevent bullet movement during recoil. I look at it as a impulse/momentuum problem; if you have an equal force acting on two objects of differing mass the one with less mass will be moved faster & further; but both will move, hence the importance of case neck tension. Once the brass has expanded to fill the chamber it now effectively becomes part of the gun which now has way more mass than the bullet. Of course there are a lot of other things involved. When it comes to a dead soft bullet obdurating in the case, that one is going to require a lot more thought. Anyway, just my $.02 worth; great idea for a thread. Take care

-SSG Klaus

[felix]

A tight neck BR gun, for example, with boolit and shaved brass to match the chamber neck MUST have a boolit HARD enough to not close the gap upon firing with the powder/primer being used. You can tell the difference on the target when things are a little too close for comfort. The rule is to continue shaving the brass, or hardening the boolit up, until the groups settle down with that same load. ... felix

[44man]

Heavy, cases always stretch at the web of the case, not at the neck. A case that is full length sized or a chamber with too much headspace allows the case to stop against the bolt, then stretch foreward until the shoulder makes contact. Then when you size, the shoulder is pushed back making the neck longer.
This is not much of a problem with straight wall cases which lengthen very little.

[44man]

I don't know, am I that hard to understand?
I was thinking about normal fitting brass in a gun and what happens to the neck at ignition when pressure builds.
I was picturing the brass expanding, filling the chamber and the brass expansion following the bullet out of the neck instead of the whole neck opening up around the bullet.
I do not buy lead sticking to the brass either because of the boolit lube. It acts like sizing lube in the size die. It is slippery and is a lube after all. Unless some shoot unlubed boolits! But bare lead has less friction on brass then a jacketed bullet.
I am also not talking about the rest of the case, ONLY what happens to the neck and when and how it expands in relation to boolit movement.
I don't know how else to state it! Some of you cause confusion by adding in all kinds of other factors with no relationship.
Felix had a good post about bullets in a bench rest gun being hard enough to keep the bullet from expanding while in the case and making too tight of a fit in the chamber. I understand and agree 100 % but that was a little off topic. Not much though because I mentioned a soft revolver boolit expanding into the brass and chamber. Does this cause higher pressure in the revolver?
Thinking caps guys! I don't know the answer but I don't think the whole neck jumps open so the boolit is loose before it leaves the neck which is what I have read for years.
Let's use Felix's post for an analogy. Everyone says you need .002" clearance around the neck so the neck will expand to release the bullet. What happens if you use a hard bullet and the brass is a perfect sliding fit in the neck. Does the brass have to expand to release the bullet? Does not the bullet just move with the case tension as the only resistance?
Or is the .002" only a safety factor to allow for a bullet that bumps up making the fit too tight in the neck? Or is it for brass thickening in the neck as it flows foreward from the web?
Oh, nuts, I gave you too much all at once!

[Heavy]

Sorry guess I miss understood the basic thought of the thread. I was speaking of the brass rolling with the force wave and the reaction of the bullet and case neck area of contact. Before the brass can roll forward pass the crimp and release the bullet the material differences has a binding effect plus if the projectile is soft the binding is even tighter. You can still get the smoke cases with jacket projectiles and you know that they are hard enough. Point being that neck tension, bullet hardness, crimp, powder quickness, all have there part to play. But I believe that the powder has the greater effect than the crimp or the neck tension up to a point. Breach seated bullets eg. Guess I will go set in the corner - think I confused myself.

[44man]

It's OK, your thoughts add to it. I am confusing when I post all the time.

[klausg]

I can tell that this one is going to get really interesting. My thoughts: as the powder burns & pressure is built, it will act on everything equally. Initially, due to case neck tension, the bullet & neck are effectively one unit with more mass than the balance of the case; i.e. the brass expansion starts from the aft end of the case. As soon as the bullet begins to move, whether from increasing pressure or the brass expanding or both it becomes a seperate object and the remaining case neck will expand to fill the chamber. I THINK that the bullet has to start moving before the case neck has expanded fully, but that the case neck expands to fill the chamber prior to the bullet leaving the case mouth. Anyway, just my thoughts I will now join 'Heavy' in the corner and start thinking about what goes on with scheutzen, (sp?) rifles. GREAT thread topic.

-SSG Klaus

[Heavy]

Klausg Iam with you. Pull up a chair buddy.

[versifier]

44Man, I do believe I understand what you are getting at and it makes good sense to me. I think I have restated it clearly. Correct me if I err:

Operating on logic alone here, this is the process as I visualize it. (Or my private hallucination if you prefer :mrgreen: ) After initial powder ignition where the case wall obturates to the chamber wall, I think that the neck expands in a wave behind the forward moving bullet/boolit, like a reverse of the neck sizing process. This would mean that the chamber neck is already sealed when the projectile has finally cleared the case neck.
This makes more sense to me than the image of the neck opening all at once then the bullet/boolit starting to move - there is no outward force on the top of the case neck until the projectile has cleared it and the pressure of the gasses force it against the chamber neck. Or the image that it obturates all at once after the bullet/boolit has cleared - there is obviously outward force acting upon the case neck progressively behind the moving projectile. For it to happen all at once appears to defy logic and seems to me to cross the line into the realm of magic.

Consider:
With a slight undercharge, soot will be found on the neck and maybe the shoulder (the case walls obturate but not the neck), where as with a gross undercharge, there is soot all over the case body (no obturation of case or neck). So, there can be a situation where there is just enough gas pressure to "pitui" the bullet out without noticable effect on the case neck (no obturation), but we are talking about a squib load way, way below the normal working pressures of a cartridge when it happens. Obviously, obturation can and does happen by degrees, so why not at normal working pressures a progressive obturation of the neck as the bullet/boolit moves through it and out into the barrel?

[felix]

The boolit expands before the neck expands. In all cases, literally. For the case (neck) to expand, some force must push it out into the chamber. It cannot do that unless the boolit has moved. This is why a tight necked gun must be treated with respect! ... felix

[Bass Ackward]

Ok. This is a nice subject to continue our discussion as they play hand in hand. So I give you something else to digest.

What happens to brass ..... all depends. Bob tried to tell you that in another thread about my brass testing. The type of cartridge also makes a difference in what happens. 44 has noticed this with primer selection as the space factor is increased.

If you take any action that delays the bullet travel you increase the time for pressure to build. If pressure builds, brass is going to expand. The rate at which it builds before the bullet over comes inertia or any delaying action you take will alter how the brass performs.

Using a heavier bullet with the same powder speed will cause different action than a lighter one. Your bullet design choice makes a difference as if a larger percentage of your weight is outside the case than another style that is inside the case filling space and increasing pressure. Crimp design has more effect than crimp level itself. (Try taking a TBL design with a heavy crimp is like using your finger nails to try and grip a baseball.) It won't be as effective or offer as much strength as a light crimp in a long grooved Keith design which is like wrapping your whole fingers around it. Bullet hardness you recognize. What about a difference in the brass thickness and anneal itself?

What about bullet diameter? If you seat into the lands in a rifle or up against the taper in the throats of a handgun, then the bullet is hanging in free air before it starts to move. Neck tension and crimp become non existant.

So there are many situations that we, the reloader create, and different senarios that unfold based upon the cartridge we are using and what choices we make in the whole reloading / shooting process. Being able to recognize which condition we want to create to assist us is paramount to success.

So my question to you all is. "Does it really matter what happens to the brass?"

[Bucks Owin]

The boolit expands before the neck expands. In all cases, literally. For the case (neck) to expand, some force must push it out into the chamber. It cannot do that unless the boolit has moved. This is why a tight necked gun must be treated with respect! ... felix

Huh?

How can the bullet expand without the "neck" expanding right along with it?

And personally, I think this whole discussion becomes moot if the throats are too small and have to "resize" the bullet before it ever leaves the chamber...(which isn't unusual in wheelguns)

$0.02

Dennis

[44man]

There is a question of interest. Take a tight chamber and have the bullet expand and force the brass into the chamber neck hard, then take a looser chamber and have the bullet expand more and still force the brass hard into the chamber neck. Why would there be a difference in the pressure? If a jacketed bullet does not expand and I don't believe they do to any extent, the pressure should be the same in either a tight or loose chamber. (Other then a difference in case volume from brass expansion to fill the chamber.)
Versifier is seeing it like I am. So if the bullet moves before the brass expands the neck behind it, why do we need .002" in a rifle for neck expansion?
I can see a problem if the neck on a loaded round is larger then the chamber neck and the powerful camming action of the bolt forces the round into the chamber and squeezes the brass extremely tight into the bullet. But why would a round that fits the neck perfect with a nice sliding fit create more pressure then a looser fit? Don't we do it all the time with oversize revolver boolits that barely chamber?
This brings up another funny thing; I shoot two boolits out of my .475. Both are the same weight, alloy and diameter. One has a gas check and the other is PB. I have to reduce the load 1/2 gr for the gas check boolit or cases stick. I can actually increase the charge more for the PB without sticky cases. Why doesn't the PB expand and force the brass into the chamber and raise pressure?
That should make all of you scratch your heads!
I have another thought but will wait until tomorrow.

[klausg]

44 man-
I think I'll scratch my hair out over that one; though I've got duty tonight, and nothing better to think about, other than Heavy's point about a breach seated bullet. That one reallly doesn't make sense. Quick thought, and feel free to poke major holes in this theory, maybe as the bullet obdurates it is stretching the GC along with it; and the GC being harder than lead... I think I'll go back to my corner seat now. Take care

-SSG Klaus

[Wayne Smith]

Keep in mind that breach or muzzle seated/loaded bullets are already at bore diameter, no obduration needed. They are already fitted to the rifling and are just being pushed up the bore. If the bore is tapered and lapped correctly they can be blown up the bore with mouth pressure alone. It is a completely different scenario and probably doesn't pertain to this discussion.

[44man]

I forgot to mention that both of those .475 boolits are cast very hard and water dropped. I add tin and antimony to WW metal. I also use slow powder, 296, with very tight case tension and a firm crimp. Both are super accurate.
The accuracy point is also strange for each boolit.
The GC one shoots the tightest group with 26.5 gr's but cases stick and I have to reduce to 26 gr's where accuracy falls off a little from less then 1" at 50 yd's to 1" or a shade more.
The PB is the reverse and shoots best with 26 gr's, as small as 5/8" groups, but when increased to 26.5 it opens to 1" or a shade more. I can increase the load to 27 gr's without sticky cases but groups open more.
The group in my picture to the left was shot with the GC boolit and 26 gr's.

[44man]

The thing I was thinking about yesterday is what is the effect on the neck when using a boat tail bullet or a bevel base boolit? Seems like a wedge area is a nice place for pressure to build and try to force it's way past the bullet. A good place to pack powder into also.

[Bass Ackward]

So if the bullet moves before the brass expands the neck behind it, why do we need .002" in a rifle for neck expansion?



44man,

You are not thinking 3 dimensional. It's for the same reason you trim your brass. As pressure builds, brass begins to flow forward before the bullet moves or at least before it moves completely. If the brass is too long, it hits the end of the chamber and is directed into the bullet forcing a CRIMP. The tighter the neck, the worse this crimp becomes. IF there is plenty of slack and most commercial cartridges allow at least .006 radius, then this is less likely or the crimp won't be as strong.

In fact, sometimes someone may believe that they have reached maximum pressure on a load and they simply have created a crimp because too much brass flowed forward. So that is why they always want you to cut .010 off when you trim.

[felix]

Yes, Klaus has that one figured out. Gaschecks are harder and present a more firm engagement against the case/chamber. As the boolit moves, the force of the expanding gas is directed towards the center of the boolit, pushing the gas check even harder outwards. A whole grain of 820 difference in 44 mag with 250 grainers for the same velocity. What you observed, 44man, is correct. ... felix

[Bucks Owin]

The thing I was thinking about yesterday is what is the effect on the neck when using a boat tail bullet or a bevel base boolit? Seems like a wedge area is a nice place for pressure to build and try to force it's way past the bullet. A good place to pack powder into also.


BT bullets DO increase the rate of erosion in rifle barrels slightly compared to flat base boolits due to a wedging action of powder gases from what I've read*....

FWIW,

Dennis

*Think it was a Jim Carmichel's "Book Of The Rifle". A guy who's firearms savvy and knowledge of ballistics is unquestionable IMO...

[44man]

Now we are getting somewhere. Couple that in with the additional friction of the gas check against the brass
Bass, you have to explain the "crimp" thing better. If the brass is flowing foreward at every shot and running into the throat to form a crimp, where does the brass go? This would mean a growth in length (figuring a case starts .010" under, or trim length) of .015" to .020" and the brass would need trimmed after every firing.
Also if there is room in the neck area of the camber, brass would thicken at every shot and would have to be reamed or turned after every firing.
Now take a neck sized case that most of us use, where the shoulder is in contact with the chamber, (zero headspace) where can the brass move foreward at? It can only move outward to eliminate the springback from the last firing.
Let's take a case that has been sized too much and the shoulder set back. Now there is too much headspace so the firing pin will drive the case foreward. The pressure will lock the brass in the chamber and the only place brass can go is to the rear where it stops against the bolt face, stretching the case at the web. Now, when that case is sized and the shoulder set back again, the neck will lengthen and need trimmed after several firings. The neck does NOT lengthen when fired!
Since I rarely have to trim brass and I only have to neck turn new brass to make the walls even and have never measured any brass thickening in the necks, what happened to that brass?
The only time the shoulder can move foreward is with a rimmed case and zero headspace on the rim, and the shoulder set back by too much sizing. Since size dies are made to limit the shoulder setback, this doesn't amount to much.
Rimmed and belted cases tend to grow in length faster unless they are also headspaced on the shoulder where they should be.
You are going to have to prove that theory!

[Bass Ackward]

1. Bass, you have to explain the "crimp" thing better. If the brass is flowing foreward at every shot and running into the throat to form a crimp, where does the brass go? This would mean a growth in length (figuring a case starts .010" under, or trim length) of .015" to .020" and the brass would need trimmed after every firing.

2. Also if there is room in the neck area of the camber, brass would thicken at every shot and would have to be reamed or turned after every firing.


3. The neck does NOT lengthen when fired!

44man,

1. Brass is elastic. It springs back. That goes 360 degrees in every direction. Pressure makes brass elongate once it encounters the perimeter of the chamber. At the end of a chamber, you have a .... ledge that may have a taper on it. Once the brass encounters this ledge, it starts to thichen. If the neck diameter won't allow expansion enough, the grip is increased on the bullet. In severe cases the brass could be forced down the taper at the mouth causing an actual crimp.

2. Brass does flow forward. Most tapered cases actually fail because of a bright ring around the base where it has been thinned and is fixing to seperate. Brass thickens at every firing at the front with high pressure loads. I have reaming dies and ream about every 7th firing. Some cartridges get it every 5 if I am serious. And they do remove metal that actually thickens from the shoulder out. Some people refer to this location as the "donut". I speculate that this "donut" is actually responsible for most of the old wives tale about never seating a cast bullet below the neck on a case. Because this donut is hard and thickened and results in sizing of the bullet's base and possibly removes the check, especially if it is a Lyman check.

3. Well it does for me. On some of my 60,00 psi cast loads with a 458X2, I can show you .300 on one firing with new brass because there is no shoulder to retard the forward motion. Just so you don't think that was a typo, that's almost 3/16th ". I can show you necked sized brass that elongates in other cartridges too. Many people incorrectly believe that sizing alone is responsible for lengthening. That was the reason for Ackley Improved cartridge designs because eliminating body taper and using a sharp shoulder minimized forward brass flow. Thus extending case life.

Plus, you have a misconception about sizing. There is absolutley no difference in the headspace measurement between a case that is neck sized and one that is full length resized when the dies are set up properly. The shoulder measurement is NEVER moved. This is what establishes your headspace on bottle necked cases. And this is the problem that occurs with reduced cast loads when the firing pin shortens this distance by knocking the shoulder back on the case. That is why I always seat my rifle bullets into the lands. It stops any stretching in the web area and puts expansion out where it should be.

But on full length sizing, only the body sides of the case and neck are sized. Some people believe that it is better to leave the sides entirely so they neck sized only. But no change in headspace results.

[buck1]

Bass said
"Well it does for me. On some of my 60,00 psi cast loads with a 458X2, I can show you .300 on one firing with new brass because there is no shoulder to retard the forward motion. Just so you don't think that was a typo, that's almost 3/16th"

I dont doubt your word!! But that seems extreme to me. It would seem to have a VERY VERY FIRM GRIP ON THAT BOOLIT!
With that in mind,I would conclude: The base of the bullet in the case is swelling to the point that it pushes the brass in to the chamber very hard, wile the bullets still in the case. and to a point answering the origanal question. Not to swell the bullet would need to be a min of BHN43 or so.
And would that reduce the length increase?? .....Buck

[Duckiller]

I am not sure how I would test it but I believe the following happens when I pull the trigger. Will talk about .357/.44 cases since it helps me envision and describe what I think happens. limiting this to brass and bullet. Once the primer is ignited the brass containing the powder and air starts to expand. Rates and amounts of expansion vary because of varying thickness of brass. Pressure is probably not uniform since it will build where the fire is and RAPIDLY go toward the base of the bullet. This may take so fast that pressure can be assumed to be uniform. Once the pressure build up gets to the base of the projectile the brass just before base expands and because of projectile inertia the brass surrounding the base of the bullet also expands. Once the brass around the bullet starts to expand the bullet starts to move. Crimping and inertia lets the brass expansion get ahead of bullet movement. With light crimp, bullet movement may straighten crimp. Heavy crimp probably requires bullet movement to straighten crimp. because of the time involved it is quite possible for brass expansion to get to the end of the case prior to bullet movement. Don't know ,not sure how to check. 44 man's two bullets adds a real world variation that may be caused by some other factor. Cartridge size, chamber size, powder, primer, bullet, brass hardness and thickness are all things that may effect the timing of these events. Because we are dealing with the real world with many variables, repeated observations while trying to minimize variables are going to be necessary to establish any TRUTHS. When two people get contradictory results the assumption probably should be that they are both right with variables causing the differing results. Closer observation,better record keeping and open-minded analysis are going to be determine exactly what happens and how it effects accurcy. Did I understand the question? Duckiller

[44man]

Bass, no misconception on sizing! I never full length past what allows the bolt to close with slight pressure. And then only when a case gets hard to close the bolt on. But some guys set the die to a tight fit on the shell holder. And the semi auto rifles and pumps need the case sized down.
I have shot a lot of mighty hot loads and never had what you describe. Some of my most accurate loads were 2 or more gr's over listed max. I can't imagine what you are doing! I have cycled these cases over 20 times without getting metal with a reamer or finding thicker necks.

[Bass Ackward]

Bass, I can't imagine what you are doing! I have cycled these cases over 20 times without getting metal with a reamer or finding thicker necks.


The 458X 2 uses a heavy, belted magnum case cut off at 2" that was designed for magnum pressures of 65,000 psi with a shoulder to prevent brass flow. If I do not neck ream the space where the bullet rests, pressure will be higher than the 60,000. Even though the clearance is technically there in the chamber to allow it. That .... was the point. Same powder charge, same length case only reamed and no lengthening takes place. I have been up to 75,000 psi with lead in this rifle which starts to get a little .... hot. That is why they call it experimentation.

And 44man, I get brass flow in a 30-06 at 34,000 psi using lead. It takes 5 loadings to see it and at 7 the donut starts in ernest. The softer my anneal on the brass, the faster the flow. I can shoot that same batch of 30-06 brass at 28,000 psi 10 times and the brass stays the same length. So sizing isn't the reason for lengthening of brass. Want more proof and mind screwing information? OK. The same lot of 30-06 brass fired with 22,000 psi and the neck will actually SHORTEN over 10 firings while headspace remains THE SAME. All my 06 brass is full length resided. So if sizing was the only reason for brass lengthening what happens here? Bottle necked case you say? OK. I have 44 Mag cases that are .005 shorter today after at least 20 loadings than when they were new. They have never been trimmed. Same .... lot .... of brass used for higher pressure stuff has been trimmed once already and is getting close again so they will be discarded. That's my rule.

This is a very difficult subject that I tried to get you to see. Then you need to ask just how important is knowing? Each cartridge / load condition has certain things in common. Powder ignities, the pressure wave slams into the base of the bullet and starts the seal proceedure .... from .... the .... brass. That is the only commonality. The hardness of the bullet may or may not expand with it depending on the "rate of the rise" of pressure. Remember, (think 44 Mag here) while Bullseye may peek at 30,000 psi in the throat area (.3"), H-110 doesn't peak for 1" at 30,000 psi. That means that if a hard lead bullet base needs 24,000 psi to start obturation, that bullet can be long gone from the cylinder before this happens. (Have I ever told you what an advantage Quickoad is?) So what happens to brass will depend on the reactions you took as a reloader and the measurements of your chamber. And you have to remember that there is no such thing as a perfect seal. That's why one guy needs neck tension and one much less. Why one guy sees more effect from crimp than another. Why crimp has more effect with fast powders and less with slow. Etc, etc.

[44man]

Bass, I agree that it is just not that important. Just have to prepare the brass properly. I understand now about what you are getting, considering the pressures you are playing with.
Brass will almost always shorten with the first firing unless very hot loads are used in a rifle. Most new brass is too small for certain chambers so it expands outward and gets shorter in the process. If very light loads are used it takes more then once for the brass to reach the chamber walls. You can see it with the powder residue on the outside of the case and some just never does fill the chamber. Shoot a very light load with new brass and it shortens, then shoot a hot load with that brass and it will shorten a lot more.
I have hundreds of .44 cases that were trimmed once to make them even and have never needed trimmed again.
Then there are those confounded 45-70 cases I use in my revolver that have been trimmed twice already. I use light loads. But I have to full length them so I get case tension on the boolit. The tapered die will not do it when I try to neck size with it. I need a neck size die, I think Redding makes one.
The right target is 10 shots from the 45-70 and the left is 5 shots from the .475. Shot at 50 yd's.

[Bass Ackward]

Then there are those confounded 45-70 cases I use in my revolver that have been trimmed twice already. I use light loads. But I have to full length them so I get case tension on the boolit. The tapered die will not do it when I try to neck size with it. I need a neck size die, I think Redding makes one.



44man,

Yes. And that is why you get into case design and internal dimensions. The 45-70 and 45 Colt were designed to handle different pressures. So cases (brass) do different things at different thichness and pressure levels.

And as such some cases should not be operated at higher pressure levels or case life suffers accordingly. When you place large capacity cases in a short barreled environment, you are limited in powder speed selection that can raise velocity levels or extend case life considerably. You are well aware of that by now. :grin:

Oh my goodness, is that LQA on that bullet from the left target? :grin:

[felix]

I had just got done experimenting using 454 Casull brass versus 45 Colt brass. The Casull brass, even thicker than the Colt brass but smaller in initial manufactured diameter, did not give any advantage over the Colt brass using the same load. It seems the smaller diameter takes precedence over the thickness of the brass in terms of brass destruction with large chambers. Both cases were factory new. Of the older cases, mucho fired, the standard Colt cases seemed to fare better. So, initial case diameter is more important than case thickness as determined by this one experiment. ... felix

[Bucks Owin]

44man,

Yes. And that is why you get into case design and internal dimensions. The 45-70 and 45 Colt were designed to handle different pressures. So cases (brass) do different things at different thichness and pressure levels.


This made my anntenae perk up. Surely you don't subscribe to the myth of the "weak" .45 Colt case do you? If so, I have a John Linebaugh article for you! :coffee:

A .45 Colt lover,

Dennis

[felix]

Dennis, after the experiment just done, I don't think "weak" brass actually enters the equation at this juncture. The outside diameter of the case versus the chamber internal diameter is the thing to watch. ... felix

[Dale53]

I have been watching this thread with MUCH interest. I get one thing out of it above all others:
"The more we learn, the less we know!" In other words, the more educated about reloading we become the more we realize that there is a LOT that we do NOT
know.:mrgreen:

Incidentally, 44man, impressive loading AND shooting!

Dale53

[44man]

Bass, the 45-70 in my revolver generates very low pressure for the velocity. I am generating less pressure then the .45 Colt with the same weight boolit with 375 fps more velocity. The .45 generates less pressure then the .44 at almost the same velocity with the same weight boolit.
Yes, the .45 Colt brass is STRONG!
WARNING, DO NOT TRY THIS---My friend was told to start at 19 gr's of 296 in his Vaquero with the 335 gr LBT and work up until he had pressure signs. Sticky cases, flattened primers, etc. He stopped at 30 gr's without pressure signs. I turned white when he told me. God knows what the pressure was. I can't even give you an idea of what the recoil was! It is bad enough with 21.5 gr's.
Felix, the .454 brass is longer then the .45 brass but is thicker so the internal capacity is not a whole lot more. Just barely enough to cut the pressure a little. A hot .454 load has a LOT of pressure but the .45 brass can handle as much. Not so most guns! One of the reasons for the longer .454 case, so you can't chamber them in the .45. You can load a .45 case to .454 pressure as long as it is shot in a .454 revolver.

[felix]

The Casull brass was cut to 45 Colt length. Shooting the 45 Colt brass in a Casull gun would be ideal because of the greater girth of the 45 Colt brass! ... felix

[44man]

Yes, lower pressure for the same velocity.

[Bass Ackward]

This made my anntenae perk up. Surely you don't subscribe to the myth of the "weak" .45 Colt case do you? If so, I have a John Linebaugh article for you! :coffee:

A .45 Colt lover,

Dennis


Dennis,

I won't use the term weak. But when I was shooting hot 45 Colt loads, my brass failed a lot earlier than I would have preferred.

[44man]

Bass, I forgot to answer your question on my lube. That is Felix lube and is all I will ever use. I rub it into the grooves by hand and run my boolits through an oversize Lee die to remove excess, a .476 for the .475. It makes for messy loading dies that I have to clean often, but no lube has ever been as accurate.

[Bass Ackward]

Bass, the 45-70 in my revolver generates very low pressure for the velocity. I am generating less pressure then the .45 Colt with the same weight boolit with 375 fps more velocity. The .45 generates less pressure then the .44 at almost the same velocity with the same weight boolit.


The 45-70 case design was origionaly made to operate between 8000 - 12,000 psi. Will it handle more? Sure. Does the 44man version of .... "low pressure" fall within that pressure range? I doubt it! :grin: So you trim.

Brass always talks to us. We just don't always listen or like what we hear.

[44man]

Bass, I started out with this revolver trying to just neck size with the full length die. I never had to trim. Accuracy was not what I wanted so I started to full length them and that is when trimming started. My loads are about 25,000 psi but less then 30,000 psi. I don't know what CUP would be.
My .45, .475 and .44 pressures are a lot more then that and I never have to trim. In fact they are still too short, having never grown because I only neck size them.
I have case fired 40 times with 71 gr's of FFFG and a 530 gr boolit in my BPCR that have never needed trimmed because I never size them.
Yes, sizing makes cases grow in length. To get straight wall cases to grow from firing is a trick I never learned.
I thought you would be interested in the difference in group size between Felix and a hard lube in my Marlin .44 magnum. The left target is a hard lube and the right is Felix. Shot at 50 yd's.

[Dale53]

44man;
That is a serious difference! It's about time that someone shows accuracy difference instead of the old "It doesn't lead". Hardly any lube that I have ever tried leads in any "normal" loads. Accuracy is sometimes hard. Obviously, the correct lube IS important.

Thanks for sharing.

Dale53

[Bass Ackward]

I guess I am not stating my point properly about different cartridge brass.

If three cartridges 44 Mag, 475, and 45-70 are all fired with 30,000 psi, I would expect the 45-70 to be the first one to need to be trimmed. The others may never need trimming because they are heavy enough that they are designed to operate at higher pressure levels. Stretching for them should not occur until their limits are reached. In fact, they may shorten over time if not used at full pressure periodically. Doesn't matter if you full length them or not. From my experience.

[44man]

OOPS, Bass, I use Starline 45-70 brass and it is as thick and tough as any revolver brass, unlike the thin WW stuff.

[Bucks Owin]

Dennis,

I won't use the term weak. But when I was shooting hot 45 Colt loads, my brass failed a lot earlier than I would have preferred.

Not weak? Darn tootin' it ain't! Linebaugh has loaded that case to 50+K (!?!) with normal case life! Carefully fitted "tightish" chambers are his "secret"...
Your chambers may have been a little on the "loose" side....

Also IMO, when running the .45 Colt at 30+K I think one should not "full length" size repeatedly, especially with carbide dies. That and a minimum of mouth flaring will see .45 Colt brass last just as long (or longer) than .44 mag brass...

As has been said, the .45 Colt is actually operating at less pressure yet more velocity (equal weight boolit) than the much esteemed ".429 mag"...(As I like to call it...:D )

FWIW,

Dennis

BTW, my experience parrallels 44 man's in that I rarely ever have to trim a .357 or .44 mag case even after a dozen "full tilt" loads. If I trim, it's usually just to get equal length for crimping purposes....

[Bass Ackward]

Not weak? Darn tootin' it ain't! Linebaugh has loaded that case to 50+K (!?!) with normal case life! Carefully fitted "tightish" chambers are his "secret"...
Your chambers may have been a little on the "loose" side....

Also IMO, when running the .45 Colt at 30+K I think one should not "full length" size repeatedly, especially with carbide dies. That and a minimum of mouth flaring will see .45 Colt brass last just as long (or longer) than .44 mag brass...

As has been said, the .45 Colt is actually operating at less pressure yet more velocity (equal weight boolit) than the much esteemed ".429 mag"...(As I like to call it...:D )

FWIW,

Dennis

BTW, my experience parrallels 44 man's in that I rarely ever have to trim a .357 or .44 mag case even after a dozen "full tilt" loads. If I trim, it's usually just to get equal length for crimping purposes....


Dennis,

You have hit on the biggest problem from people that complain about full length sizing brass. And 45 Colt has generous and often tapered chambers far in excess of what is needed. Case life suffers accordingly, no matter what cartridge case / design you have. And the 45 Colts I have owned were not immune to this.

I have a line bored 44 mag that has cylinders so tight that I have problems seating some small crimp groove designs if I try to crimp them. Neck sized brass from four other 44s won't even begin to chamber. Anyone using this gun would have no understanding of some of the issues discussed on this board. It won't (or I can't) shoot one whit better with this gun than any other 44 I own, but they require tinkering until the right set of conditions are met.

Once something like this is used, it becomes easier to understand why problems arise from other bullet launchers that I own which are common to what others see. What is .... strange is I see this in rifles all the time, but just dismiss it in handguns as par for the course. Brass is the weakest element in the firing chain. Offer brass the support and alignment it needs, and operate it at pressure levels that it was intended, and it doesn't matter how you size it, it lasts longer and is stronger. But remember, recommendations for the strength of any cartrdge case is not made under ideal conditions, but a worst case senario for obvious reasons.

[klausg]

Sorry guys have been off the net for awhile, this one has been bugging me over the weekend.


BT bullets DO increase the rate of erosion in rifle barrels slightly compared to flat base boolits due to a wedging action of powder gases from what I've read*....


Okay, not meaning to blaspheme Saint Jim,:-D but if BT's erode a barrel faster, it can't be form any "wedging action". Pressure is pressure, it's going to act equally on everything, in fact if a BT does anything; it would reduce pressure by giving it more surface area to act on, (pressure=force/area). My thoughts on 44's original question are these. In re case necks I think that BT's would cause the neck to open up that much quicker, particularly in a long necked case, like a .222, where the entire bullet is contained in the neck, (less bullet to maintain case tension with, more brass not in contact with the bullet for pressure to act on. With say a 200gr in a .308 where the bullet base is going to be way down w/in the body of the case, I don't think it would make any difference, at least by the time it would, bullet movement would have made it a moot point anyway. Now I've got to catch up on all the other stuff I've missed over the weekend, going back to my corner seat now:mrgreen:

-SSG Klaus

[Bucks Owin]

Sorry guys have been off the net for awhile, this one has been bugging me over the weekend.



Okay, not meaning to blaspheme Saint Jim,:-D but if BT's erode a barrel faster, it can't be form any "wedging action". Pressure is pressure, it's going to act equally on everything, in fact if a BT does anything; it would reduce pressure by giving it more surface area to act on, (pressure=force/area). My thoughts on 44's original question are these. In re case necks I think that BT's would cause the neck to open up that much quicker, particularly in a long necked case, like a .222, where the entire bullet is contained in the neck, (less bullet to maintain case tension with, more brass not in contact with the bullet for pressure to act on. With say a 200gr in a .308 where the bullet base is going to be way down w/in the body of the case, I don't think it would make any difference, at least by the time it would, bullet movement would have made it a moot point anyway. Now I've got to catch up on all the other stuff I've missed over the weekend, going back to my corner seat now:mrgreen:

-SSG Klaus

I'm pretty sure I got that from Jim Carmichel's "Book Of The Rifle" but since I've loaned it out I can't confirm at the moment. Maybe someone else has a copy? There was quite a bit of info about boat tails in there if I remember right...

Another interesting thing about them is that they have almost no effect on trajectory until the boolit has slowed down to something around the speed of sound....

Main point is, BTs ARE harder on barrels...

FWIW,

Dennis

[Bucks Owin]

Dennis,

You have hit on the biggest problem from people that complain about full length sizing brass. And 45 Colt has generous and often tapered chambers far in excess of what is needed. Case life suffers accordingly, no matter what cartridge case / design you have. And the 45 Colts I have owned were not immune to this.

I have a line bored 44 mag that has cylinders so tight that I have problems seating some small crimp groove designs if I try to crimp them. Neck sized brass from four other 44s won't even begin to chamber. Anyone using this gun would have no understanding of some of the issues discussed on this board. It won't (or I can't) shoot one whit better with this gun than any other 44 I own, but they require tinkering until the right set of conditions are met.

Once something like this is used, it becomes easier to understand why problems arise from other bullet launchers that I own which are common to what others see. What is .... strange is I see this in rifles all the time, but just dismiss it in handguns as par for the course. Brass is the weakest element in the firing chain. Offer brass the support and alignment it needs, and operate it at pressure levels that it was intended, and it doesn't matter how you size it, it lasts longer and is stronger. But remember, recommendations for the strength of any cartrdge case is not made under ideal conditions, but a worst case senario for obvious reasons.

I like to size as little of the case as I can get away with and still have reliable chambering. You're right, the .45 Colt does have .001" of taper according to SAAMI dimension drawings and that's why I'm not fond of carbide size dies. Whatever the size of the carbide ring happens to be is what the entire case gets sized to, which in the case of the .45 Colt results in a pretty sloppy fit of the cartridge in the chamber. I've seen .45 Colts with chambers so "loose" that you could actually "rattle" the rounds in the gun! Not good....

Dennis