Secondary Pressures...

[geraldbergeron]

Just a note to all those timid souls that read this but are too smart to comment on an issue such as this. If your corn-fused don't feel bad. I have been shooting for 38 years, teaching shooting for about 28 years now, reloaded for about 22 years loading well over 150,000 rounds, am considered to be well read on the subject of ballistics and I still don't know FOR SURE what the right answer here is!
Think I will just leave it out there in the unanswered questions of life realm for now and go eat some pie. :wink:

Rifleman,

I am IN..

A paradigm is: EVERYBODY THINKS THAT, SO I MUST THINK THAT...

I do not believe in paradigms... so are you, I think...

I think that secondary pressures exist... What are their causes... I am still searching... a misfire with an advanced bullet which was fire again ? an overdose of powder ?? a duplex which bad "digestion"... a two bullets shot... ???

For sure, IMO, expert ballisticians do not deal with those situations, because they always do what must be done (?), or at least that is what they use to tell us.

Some hunters do not work like that ... When ones has shot 6000 rounds with their gun... we usually "DARE" something else, do'nt we ??

And there comes the "SECOND PRESSURE", whis is then "to much"...

What do you think ... ? That is mine and I respect any other one.

.........................................Gerald.................................................../

 

[Rifleman]

Well like I said I really don't know, so I guess I will get another piece of pie, watch TV, sit on the couch, and generally goof off as much as possible as per my usual SOP. :shock:

 

[Anonymous]

well for one thing randy, ballistians are looking for good loads not bad. there job is to develope loads that work and are safe.

Who isn't? :shock:

 

[savagebrother]

you know what i mean, they do there work in laboratory standard conditions with many hours of computations before they send one round down range. look i am not trying to say that secondary pressures are good, they're bad. just saying they exist and its usually because we tried or accidently created them without knowing it would occur.
sb

 

[Anonymous]

I'm afraid I have no idea what you mean. Do you know any senior ballisticians, personally?

 

[savagebrother]

well that was obvious when you made your first statement on this thread.
well i new jim hull at sierra from when i was about 13 or 14 and talked to him alot until he retired, and then i still bugged him some. again ballistians do not set out to find bad loads or to cause barrel bulges. as a matter of fact they shoot about a quarter of what they used to. most design is in the computer itself. no rounds are fired until they are sure of what to expect from a load. its too expensive to just load and poke and hope. which is where the savage muzzleloader was left at. its sole intention was to use smokeless to duplicate b/p substitutes and reduce recoil-that it did, but it also opened the door to alot more and in an arena that none of the ballistians ever considered much less tested. i would venture to say there is one though rb has done more testing and fired more smokeless test rounds than anyone. i would consider him to know more than anyone at any powder company. i can tell you though randy i am e-mailing several on this very subject and will copy and paste they're replies.
sb

 

[Anonymous]

You can't feel pressure, you can't see it, and strain gages do nothing unless you have a calibration load. What is the goal to the hunter?

You are misled about the body of information collected, and the amount of testing done by Henry Ball & Co. over the last 16 years, and by Savage over the last 7 years------------ it is both huge, and significant.

It it just plain silly to think it takes great effort to find a good deer load: it is really old news at this point. Ballistically, nothing yet dramatically outperforms N110 or N120 in the Savage. If you have no goal, it is not reasonable to expect the completion of it. Velocity and recoil are not always "progress." :shock:

 

[savagebrother]

no they are not. a .308 kills just as effectively as an "06"
but we werent talking about that were we. a 45/70 is still killing deer over 130 years later-why develope anything else?? your talking in circles now.
everything i am talking about is from my own real world shooting.
imr and h-4198 far exceed n-110 in velocity at accuracy and with less pressure in the savage and its barrel length. aa-2015 is the only powder to use in my .45 cal. ruger no.1, h- and imr-4198 shoot well until you try to go over 2600 and they just cant do it. 72.6 grains of aa-2015 and a 200 gr. sst yields 2800 fps and 1 1/4" at 100 yards. this load was achieved over a 2 month period of shooting and testing, not quoting someone else.
you are correct though you dont have to look far to find a good load to hunt deer with. hey if you want to use a 30-30 feel free too, but dont knock me because i want to use a .300 win mag. the savage offers all to all.
the first 5 deer i shot with a savage were with 45 grains of 5744 and a mmp sabot and a 300 grain xtp-very lethal load combo and great accuracy for a beginner, oh but i thought this was for advanced techniques and loads. mmmm
sb

 

[Anonymous]

the first 5 deer i shot with a savage were with 45 grains of 5744 and a mmp sabot and a 300 grain xtp-very lethal load combo and great accuracy for a beginner,

That load is precisely the load "beginner" and "newbie" Henry C. Ball uses to this day.

 

[savagebrother]

and my load of 70 grains of imr-4198 and a 250 gr. sst is just as lethal and has a much better trajectory. again i thought this was the advanced board. i never said it was a bad load to the contrary i stated it as an excellent load. doesnt mean its the only load. your way off subject here randy.
sb

 

[Grouse]

everything i am talking about is from my own real world shooting.
imr and h-4198 far exceed n-110 in velocity at accuracy and with less pressure in the savage and its barrel length.

How do you no it has less pressure? Did you test that, or is that reports from others? Is that what the powder is called at the gun shop? (H-4198)

 

[big6x6]

imr and h-4198 far exceed n-110 in velocity at accuracy and with less pressure in the savage and its barrel length.

I'm real curious about this as well. I'm not DOUBTING it at all. Just curious... You are using 70gr IMR-4198 and a 250gr SST? What velocity/accuracy are you getting with that load?

 

[Grouse]

Thanks for the information SW

 

[SW]

imr and h-4198 far exceed n-110 in velocity at accuracy and with less pressure in the savage and its barrel length.

I'm real curious about this as well. I'm not DOUBTING it at all. Just curious... You are using 70gr IMR-4198 and a 250gr SST? What velocity/accuracy are you getting with that load?

This is not "promoting " another board, but pressure traces of 4198 and many other loads are listed at the top of the "topic" list on Doug's board. Many pressure traces are listed here. They are very interesting to go thru. You will note that even loads of 70g+ 4198 with 250g bullets are less than virtually every book load. Take note of the 5744 loads.

 

[savagebrother]

well lets not say less pressure but but over a longer time.
if i load up 43 grains of n-110 and a 250 grain sst with mmp sabot. anything above about 50 degrees f. and i start to shread sabots. velocity is close to 2400 fps as chrono'd. with my load of 70 grains of imr-4198 i am at close to 2700 fps as chron'd and i can shoot it bare sabot at any temperature as long as i give it plenty of cool down time between shoots.
that alone should tell you what you wanted to know, besides the fact that imr and h-4198 are the primary powders s.m.i. endorses. oh hogden h-4198.
sb

 

[SW]

well lets not say less pressure but but over a longer time.

sb

I agree totally with your statement. Of course there is more total pressure or the bullet wouldn't go faster. The "peak" pressure is less and we have greater total pressure. This is just the same as a stored energy(force/draw curve) graph of a compound, or any other, bow. A somewhat lesser pressure over a longer period of time is generally preferable to a shorter, higher pressure. If nearly complete powder burn is obtained, the more powder required to get a certain velocity, the lower the pressure is. Rick Bibby pressure tested H-322 at 90gs with a 250SST, got, to the best of my remembrance, appx 2700'/sec and barely 30,000psi. This isn't anywhere near an "ideal" load but does demonstrate that very high velocities can be obtained with comparatively low pressures. The SMI which, due to breechplug design, will give blow back or at least 209 separation at higher pressures will get even greater velocity with the same load and will still have an intact 209. We can really control and select our velocities. 40-45gs with 35,000psi isn't the only arena in which smokeless MLers can operate very safely.

 

[big6x6]

Interesting that Hodgdon shows that H4198 AND IMR-4198 are BOTH faster burning powders than VV N-120 on their newest chart. Also interesting to note that SR-4759 practically always has its back up against N-120. Certainly either of the 4198s are just as much a book load as VV N-120 is.

I'd be interested in any data you might have for a 250gr bullet in the 2300-2500fps area as well as a 300gr bullet in the 2000-2200fps area...

 

[savagebrother]

well thanks sw, i was trying to put it in terms that the layman could understand easier. you know if one is tearing up sabots and one isnt it pretty clear which is developing more pressure faster. you know in retrospect, just listning to the report of a savage can tell you alot.
when shooting 5744 my gun sounds more like the pop of a shotgun.
with my load of imr-4198 it sounds just like a high powered rifle. i turned a friend on to a savage and he started out with 5744 and i told him about 4198 and he made the same statement i just made about the report. oh and as far as recoil-its about that of an "06" with 180 grain bullets.
and all this with a short barrel. i think your using 2015 arent you sw in your s.m.i. ?? with 300 gr sst?? you have a 28" barrel too???
i know i had to go to it in my .45 cal. anyway fellows what we are trying to say here is the savage and other smokeless muzzleloaders are rifles-period. so they work better with rifle powders-not pop-gun pistol powders.
these are the farrari's of the rifle world- we can do things with these guns that a cartridge gun would never think of. we have been shooting these things for a while and the self evedent truths are there. try the 4198's and start at around 65 grains with a 250 sst or around 60 with a 300 sst you'll be amased at what happens-MAGIC !!!!
sb

 

[Mountain Man]

Chuck, I'm shooting 67 grains of IMR 4198 with .75" to 1.3" accuracy. I don't have a chronograph yet, but by the results had by others, that should put me around 2450-2500 fps with a 250 grain bullet. My gun started shredding sabots before I got near that speed with N110.

I understand what Randy has said about the pressure trace needing a calibration load. He is exactly right. However, that is exactly what Rick Bibby has done. He used many pressure traces of 44 grains of 5744 under 250 grain bullets to get a very consistent trace of the internal pressure created by that load (which certainly is not even the highest-pressure book load). Then, using that peak pressure as a maximum, he has tested a variety of slower powders (N120, N130, IMR 4198, H4198, Reloader 7, 10X, H322, IMR 3031, 2015, etc.) to determine at what point these powders begin to near the same peak pressure as the 44g 5744 load.

Randy makes a good point: perhaps 67 grains of IMR 4198 is not 30,000 PSI like has been estimated. Perhaps it is 45,000 or 55,000 psi (although I don't actually believe that for a minute). But, if it is, then time-tested loads like 44 grains of 5744 and 43 grains of 4759 and 43 grains of N110 are right up there at such high pressures, too, and in fact, surpass the pressure of the load I'm using.

I'm not suggesting that IMR 4198 is better. Just that it's NOT unsafe when used within reason after careful, scientific analysis based on verifiable and repeatable observations that don't push things to the limit, but rather leave a safety margin in case of error.

 

[Mountain Man]

And to be clear, none of what has been said here is an invitation to ANYONE to just pour a larger amount of some powder in their rifle just because it's "listed" as a slower powder than one they've been using. This is the advanced forum, and I'm posting my thoughts with the trust that everyone in here will act "advanced" and treat muzzleloading like the branch of reloading that it is and not just play around haphazardly with tools that could kill or maim if treated carelessly.