O.K. Pressure in the Modern Marlin Rifle?

[jackfish]

Well, I never thought that I would resort to such a thing but, dla you are an idiot.  You ignore the evidence stated here with your tangential blather.  You just don't get it, you don't want to get or you cannot get it.  One last time: Marlin has manufactured the 1895 pretty much the same way for 32 years.  It is essentially the same rifle as the Marlin 336 and 444.  It has been scientifically determined through mathematics and testing by the shooting industry that the modern Marlin 1895 45-70 Gov't rifle has a safe maximum operating pressure of 40,000 CUP.  All your misunderstanding, misinterpretation and red herring arguments does not change that fact.  You don't have to be an expert to understand that the experts have already made this determination. dla is too stubborn or dimwitted to understand it.

[dla]

It has been scientifically determined through mathematics and testing by the shooting industry that the modern Marlin 1895 45-70 Gov't rifle has a safe maximum operating pressure of 40,000 CUP.

No it hasn't. There's a small pile of anedotal evidence that it is safe at 40Kpsi. Nothing scientific about it.

What is true is that the resurgance of 45-70 popularity has people pushing the rifle to 40Kpsi.

32 years ago there wasn't a single ammo manufacturer that even hit 28Kpsi - they all loaded closer to 21Kpsi.

And whether or not I am an idiot is irrelevant since the above facts speak for themselves.

[jackfish]

Marlin has no obligation to violate their specifications in order to accomodate people who do stupid things.

Here is an example of your stupidity.  First, Marlin does not and doesn't have to violate their specifications.  Marlin produces a rifle per their specifications and the result is, in the case of the Marlin 1895 45-70 Gov't, a weapon that can safely operate at 40,000 CUP.  Marlin's specifications for the Marlin 1895 have nothing to do with the Sporting Arms and Ammunition Manufacturers' Institute pressure specification standard for the 45-70 Gov't cartridge.  However, Marlin is a member of SAAMI and has committed to accepting and promoting its standards.  So even though it is well known, supported and documented that the Marlin 1895 45-70 Gov't has a safe maximum operating pressure of 40,000 CUP, Marlin will not recognize it.  And that seems to be your problem.  You think that because Marlin does not recognize it that it somehow cannot be true.  But reasonable people (no, no matter how much you protest that you are reasonable you have proven here otherwise) in possession of what is now common knowledge know better.

[jackfish]

Yes, I see you are still an idiot.  It has been scientifically proven that the safe maximum operating pressure of the Marlin 1895 45-70 Gov't is 40,000 CUP.  It is has been tested, it has been documented, it has been proven to be repeatable, and you therefore are an idiot.  You apparently don't even know what science is.

[jackfish]

Come on, keep replying and keep proving that you are.

[dla]

Yes, I see you are still an idiot.  It has been scientifically proven that the safe maximum operating pressure of the Marlin 1895 45-70 Gov't is 40,000 CUP.  It is has been tested, it has been documented, it has been proven to be repeatable, and you therefore are an idiot.  You apparently don't even know what science is.

Could you please post a link for this forum to read? Oh by the way, this should be link to a study/analysis done by a qualified source, i.e. not a gun rag writer.

I would really appreciate reading an engineering analysis of the M1895 45-70. Especially one that shows that the safe operating limits are 40Kpsi with Marlin's manufacturing process. Note: An engineering analysis isn't something a gun rag writer does. Nor is it something that the writer of load manual prolog offers. I know. I are an inginyr.

Honestly, if you would provide that information, I will drop all my arguments to the contrary.

[jackfish]

See, you did it again!  So you don't know what science is.  An engineering analysis is not necessary to prove the modern Marlin 1895 45-70 Gov't has a safe maximum operating pressure of 40,000 CUP.  There is more than enough conclusive evidence (if one were smart enough to recognize it) that proves it. You just conveniently ignore it, thinking it takes some kind of structural analysis.  Well, it doesn't.  It just takes understanding the available information and coming to a reasonable conclusion.  Things you obviously can't do.

[dla]

See, you did it again!  So you don't know what science is.  An engineering analysis is not necessary.....

What you mean't to say is "An engineering analysis does not exist".

You know, you may be on to something. A few people claim to have been visited by extra-terrestrials. The checkout lane magazines have written about it for years, and since those magazines are still in business, people have read these stories. Therefore, by applying your logic, aliens exist.

Have a nice day

[dla]

I'd be willing to bet that an overloaded 1895 will launch the bolt into the shooter's face before the barrel blows.

The reason I discount bolt thrust is that it is improbable at pressures below the yeild strength of the brass (~50K psi and up). The bolt thrust calculations posted by Jay assume that the case doesn't grab the chamber walls - which normally it certainly will. So in a real sense there is very little bolt thrust unless you greased the case and chamber before shooting.

Since I've never seen a report showing the material strength of the locking lug (see previous long-winded discussion on 1895 operating limits), I can't assume anything because of the thrust of other cartridges. Especially since none of them operate beyond the yeild strength of the brass. I've also never heard of anyone tearing their 1895 apart and discovering that the lock lug was peened pretty badly from handling hot loads. Maybe we'll learn more as people shoot the 480/475 hot pistol cartridges.

Lastly, I suspect that area affected by hoop stress along the chamber and first inch of barrel would be much closer to bursting long before the much smaller increase in bolt thrust is likely to shear the lug and rip off the lever tip.

[jaycocreek]

Let me throw some gas on this fire. During a conversation with Jim West (Wild West Guns) I asked him about the strength of the new Marlin 1895 and Win 1886. He said Marlin was good up to 50,000. He said the action was plenty strong enough and that they had done all sorts of testing on the Marlin actions during the course of their making the 457 magnum and doing some other testing with the 50 Alaskan. He said he hadnt done any testing with the 1886 action.
-------------------------------------------------------------------------------------
Name with held,but is was one of our Alaskan boy's talking to Mr.West himself.I can see how they(Wild West Guns) would try and take the Marlin as far as they could to make a more powerfull cartridge since the 45-70 is limited to SAAMI for some and 40,000CUP for other's.I guess they saw like other's and the Proof Pill Illistration the Marlin action is a strong one if not very strong as there test seem to prove.If I remember correctly,there .457 Wild West Magnum is loaded to 45,000 CUP.Hummm :eek: But they say it's good to 50,000.Hummmm :lol: Not coincedental or anything.Geez the .450 Marlin at 43,500 PSI and the .457 WW Mag(I know it's different)but 45,000 CUP?

I am confused,I'll just shoot my .22,I know it's safe.Isn't it?Ha Ha.  
Have a good one.Jayco.

[Mac11700]

Mac

[jaycocreek]

As far as the yeild of the brass being 50,000 or so,I,m not sure what you meant by that.George Weber of Hodgdon Powder tested Winchester Brass under controlled circumstances to 70,000 with no splitting,primer pocket problem's and they just fell out of the barrel.And Winchester is the largest capacity or thinnest of all the 45-70 Brasses.
If yield means there is know case expantion,then I need my eye's checked because even the Remington Factory 405 SP has some expantion.Now Buffalo Bores 350 grain(Starlin brass) has quite abit more expantion than the Remington.I know most or some don't agree,but if you take the expantion from Remington and then Buffalo Bore(Being a Max Load) you see that Brass expantion happens gradually untill it has expanded all the way to the diameter of the chamber.

I don't really know or want to know what's gunna give out first,but I know it won't be the Brass or primer.

Wearing a  Welder's Helmet when shooting or Hunting is know fun at all.I wonder if they come in Hunter's Orange? :lol:
I think I will stick with 40,000 CUP as a Max just for Hunting loads and the rest are for fun and packed with less powder.I am sure there is a little Lee-Way for a few over loads.I have seen that myself and backed off real fast.But still there were No visable sign's of High Pressure other than Velocity and recoil.

Just my opinion.Jayco.

[dla]

What the heck does the bolt do? I guess it's just there to hold the primer in place .

Funny, but that is what happens most of the time. Normally the primer is seat slightly below the case head.  The firing pin dents the primer inward. Pressure drives the primer out causing it to flatten against the bolt face.

How much does the primer move? No more than the headspace. At what point is it moving? I'm not sure, but I believe the primer moves most at the beginning stages of combustion, long before Max pressure.

I'm not positive about this, but it seems to me that the pressure driving the primer out is way higher than the pressure required to seat it. If the case head were moving backward against the bolt, the primer would simply be "reseated". But instead I believe the primer is being mashed against the bolt face by significant combustion pressure - far in excess of the pressure required to seat the primer.

I'm also assuming that the case can move rearward a small amount before the brass "grabs" the chamber, but the pressure at this point is pretty low.

Good discussion. Thanks.

[dla]

As far as the yeild of the brass being 50,000 or so,I,m not sure what you meant by that.

You're right about brass - it depends on the manufacturer and application. Just like steel, brass can be made harder/softer after the drawing/forming process. This is most common with pistol brass. An example is the good-ol, low-pressure .45acp. When Starline decided to support the "ultra-hot rod" 460 Rowland (1/16" longer case) they added more brass to the web and they changed the annealing process.

A fellow who goes by the handle "ClarkM" did some destructive testing with the .45acp by rechambering an old Mauser. He discovered that the brass started to fail before 40Kpsi. I mention this for two reasons (1) I appreciated Clark's testing and (2) it shows that the brass is not particularily strong for .45acp.

Winchester is probably running all of it's brass through the same process, resulting in pretty tough brass for 45-70 applications. Thanks for the info.

[dla]

Like CoyoteHunter has said several times before...if you can increase your effective range and harvest your animal  cleanly

You aren't increasing the "effective" range. What you are increasing is the "point blank range".

Effective range is a combination of a bunch of factors, but the most important is the inherent accuracy of the rifle/cartridge/shooter combination. That combination usually limits "effective" range to no more than a few hundred yards.

Point blank range is the distance at which you can hold dead on without elevation holdover and place a bullet in the kill zone of your quarry. Obviously "point blank range" differs for ground squirrels versus Bison.

[Mac11700]

Like CoyoteHunter has said several times before...if you can increase your effective range and harvest your animal  cleanly

You aren't increasing the "effective" range. What you are increasing is the "point blank range".

Effective range is a combination of a bunch of factors, but the most important is the inherent accuracy of the rifle/cartridge/shooter combination. That combination usually limits "effective" range to no more than a few hundred yards.

Point blank range is the distance at which you can hold dead on without elevation holdover and place a bullet in the kill zone of your quarry. Obviously "point blank range" differs for ground squirrels versus Bison.

DLA:

AHHH I think you should look up the word bro...
ef·fec·tive    ( P )  Pronunciation Key  (-fktv)
adj.

1)Having an intended or expected effect.
2)Producing a strong impression or response; striking: gave an effective performance as Othello.
3)Operative; in effect: The law is effective immediately.
4)Existing in fact; actual: a decline in the effective demand.
5)Prepared for use or action, especially in warfare.

1)Having an intended or expected effect.

I draw your attention to definition #1....

When I increase the velocity of my 300 grain Nosler Partition load I have increased my effective range....do you know why???...I'll tell you...I expect it  to shoot a little flatter and allow me to harvest my animals a little further out than(cleanly) if I was loading it to the cowboy levels of velocity.I know the outcome of my actions in other words.

As far as the accuracy only I know what that would be.If my rifle wasn't accurate then my effective range would be much less...since I am the person reloading the cartridges,and doing the shooting,I am the controling factor when it comes to the ammunition used, and only I will know if the outcome will be as expected

I suggest you consult a dictionary next time please,prior to taking me to task for inappropriate usage of my choice of words/wording.

Have a Great 1

Mac

[w30wcf]

Jarhead Ed,

Good morning.  As dla indicated, the pressure against the side walls of the case do, in fact, retard bolt thrust, and in the case of the .30-30 with 38,000 c.u.p. loads it is practically eliminated as the test performed by noted gunsmith P.O. Ackley below indicates.

To prove this theory that bolt thrust is reduced by the pressure on the side walls of the case, he took a .30-30 Model '94 Winchester and backed the barrel out 1 thread and fired it.

The case stayed in the chamber and the primer backed out the distance of one barrel thread. He then backed the barrel out one more turn and had to lengthen the firing pin to set off the primer. Result? As before, the case stayed in the chamber and the primer fell out.

Finally, he threaded the barrel back in and removed the locking lug from the receiver(!), leaving the bolt with no means of support other than the finger lever. He fired the rifle several times and, astoundingly, all cases stayed in the chamber and appeared normal except for excessive primer protrusion.

He certainly proved his point.  However, that does not mean that every cartridge will totally lock itself in the chamber (different diameters, different lengths, etc.) but it does prove that there is indeed plenty of pressure on the side walls to retard rearward thrust.

Obviously, once the elastic strength of the brass is exceeded as chamber pressures rise, the cartridge case itself will stretch to the headspace dimension.

Sincerely,

w30wcf

[w30wcf]

dla,

I decided to call afriend of mine that works in a ballistics lab.  To your point, he confirmed that the maximum SAAMI pressure for the .45-70 is 28,000 lbs.  He said the only reason there is data for 40,000 c.u.p. .45-70 loads in the 1895 Marlin, is because the same action is used with the .444 Marlin whose SAMMI rating is 44,000 cup and with the .450 Marlin whose SAMMI rating is 40,000+ cup.   Asked about the possibility that different materials, strengths, are used in the .45-70 vs. the .444 /.450, he said that Marlin has never stated they are different.

He went on to say that awhile back he received a call from Marlin regarding a wrecked .45-70 Marlin that had been returned from a customer.  He described it as a case of "catastrophic failure" due to extremely high pressure.  The back of the cartridge case had blown out, dumping  plenty of gas back into the receiver, blowing off the extractor, a few other action parts, the magazine tube and forearm.   Astoundingly, the action held, and the barrel was still in one piece, still attached to the receiver.   Upon examination, Marlin determined that the locking lug was still firmly in place but was set back .004".

Asked, what kind of pressure would cause that to happen, he said 70,000+ psi(!).  He also said that  it was a tribute to the strength   of that 1895 .45-70 Marlin.

Have a good weekend!
w30wcf

[jaycocreek]

w-30- Good thread and very interesting.I sure like to here it from those that know or the Horses Mouth.70,000 WOW :eek:

Best of luck.Jayco.

I'll have to read that again but my wife want's the computer.

[John A]

This is e very interesting topic and one that has been debated alot on the old marlin site. As far as the tests P.O did with the Win 94 in 30-30 Improved, it was done to show that bolt thrust was less with an improved case with minimal taper! I saw first hand a catastrophic failure of a 95 a few years back and the bolt held in place. The chamber split blowing the forearm off and bending the mag tube down and out of the frame at a 90 deg angle, the frame split down through the scope base holes but the bolt held in place and the shooter was shaken but okay! He was using small charges of Unique and we think he double or triple charged a round.

 I know folks enjoy debates but damn this one is old and I don't think anyone will ever be completely satisfied with the answers. I personally don't get to worried about running the pressures up on the marlin as I'm shooting a wildcat based on the 450 case and using ballistic software it looks like I'm over 50,000 cup and to date with two 95's in this wildcat no problems. I talk to Mic McPherson on a regular base and go with his experience and I don't worry much about it.


John Anderson
www.rockislandballistics.com

[Coyote Hunter]

Like CoyoteHunter has said several times before...if you can increase your effective range and harvest your animal  cleanly

You aren't increasing the "effective" range. What you are increasing is the "point blank range".

Effective range is a combination of a bunch of factors, but the most important is the inherent accuracy of the rifle/cartridge/shooter combination. That combination usually limits "effective" range to no more than a few hundred yards.

Point blank range is the distance at which you can hold dead on without elevation holdover and place a bullet in the kill zone of your quarry. Obviously "point blank range" differs for ground squirrels versus Bison.

dla -

Your argument is a silly one at best.  

Yes, by increasing velocity you increase Point Blank Range. But you may well also be increasing effective range at the same time, as, contrary to your assertion, "inherent accuracy of the rifle/cartridge/shooter combination" is not necessarily the primary factor that determines "effective range".

While there is are accepted definitions for "Point Blank Range" and Maximum Point Blank Range", there is no such agreement on a definition for "effective range".

"Accuracy" is simply a measure of repeatability.  I can shoot my Marlin 1895 and 375 accurately out to at least 500 meters, as I proved to myself last fall while knocking down the rams at the NRA Whittington Center.  But 500 meters is far beyond what I consider the effective hunting range for those rifles.  In this case, trajectory is the determining factor in what I consider "effective range", as I was aiming 12 to 13 FEET above the intended target.

By contrast, I have shot an AK-47-type rifle at 100 yards and had a hard time holding a 12" circle.  The inherent accuracy of the rifle is what I would consider the primary determining factor for the "effective range" for that rifle.  

My Ruger .44 Mag Super Redhawk and I have no trouble hitting the kill zone of an elk at 200 yards, but once again that is well beyond what I would consider the "effective range" for elk, as the retained energy at that range is well under what I think it should be for game animals that size.

Given reasonable retained energy, many hunters, myself included, would consider "effective range" to that range at which a bullet impacts the target within a pre-determined area relative to point of aim.  (In my own case, I tend to think in the order of 3" above to no more than 10" to 12" below point of aim for mulies and elk.)  Note that this definition is independent ot Point Blank Range or Maximum Point Blank Range, and is, in fact, completely independent of what range the rifle is zeroed at.  Note also that for rifles zeroed under Maximum Point Blank Range that increasing velocity also increases the "effective range" using this definition.

[Mac11700]

This is e very interesting topic and one that has been debated alot on the old marlin site. As far as the tests P.O did with the Win 94 in 30-30 Improved, it was done to show that bolt thrust was less with an improved case with minimal taper! I saw first hand a catastrophic failure of a 95 a few years back and the bolt held in place. The chamber split blowing the forearm off and bending the mag tube down and out of the frame at a 90 deg angle, the frame split down through the scope base holes but the bolt held in place and the shooter was shaken but okay! He was using small charges of Unique and we think he double or triple charged a round.

 I know folks enjoy debates but damn this one is old and I don't think anyone will ever be completely satisfied with the answers. I personally don't get to worried about running the pressures up on the marlin as I'm shooting a wildcat based on the 450 case and using ballistic software it looks like I'm over 50,000 cup and to date with two 95's in this wildcat no problems. I talk to Mic McPherson on a regular base and go with his experience and I don't worry much about it.


John Anderson
www.rockislandballistics.com

John A:

Would this be a 40cal wildcat,or a 35 cal??? I would be most interested in hearing/seeing something this myself.

Mac

[dla]

Coyote: You just gave a great explanation of "effective" range, using examples of (a) your own shooting skills (b) the sloppy Klashnikov design and (c) a powerful handgun. Great job! (and good shooting too).

Now don't get distracted and forget what you were describing - effective range. Point blank range or Maximum point blank range is a different subject.

Here's another example: The 155mm M198 launches a 90+lb projectile out the muzzle at ~1700fps. If the target is a 6ft man, and you must actually hit the man anywhere from head to toe, then the maximum point blank range is 450yds (assumes the bore is at 5ft). However the maximum effective range against men is 13.9 miles assuming the fragmentation pattern of a particular round and the minimum effective range is a little over a mile for high-angle drop. Goofy example, I know.

What increasing velocity does is directly increase maximum point blank range. Adding a scope increases maximum effective range (usually).

This really should be another thread.

[dla]

dla,

The back of the cartridge case had blown out, dumping  plenty of gas back into the receiver, blowing off the extractor, a few other action parts, the magazine tube and forearm.   Astoundingly, the action held, and the barrel was still in one piece, still attached to the receiver.   Upon examination, Marlin determined that the locking lug was still firmly in place but was set back .004".

Asked, what kind of pressure would cause that to happen, he said 70,000+ psi(!).  

What your friend said makes perfect sense. Somewhere past the yield strength of the brass, the case let go. The high-pressure gas leak was nasty, but far less lethal than the potential pipe-bomb if the case had held.  Thank you for the post as it reminds me that there is a built in safety mechanism of sorts - the cartridge case. And the venting mechanism left the shooter's head intact.

I wonder how high the pressure actually went in order to increase the headspace .004"? Either: the receiver stretched, the barrel threads stretched, the bolt warped, or the lug peened.

[Coyote Hunter]

... What increasing velocity does is directly increase maximum point blank range. Adding a scope increases maximum effective range (usually).  ...

Given the definition for "effective range" that I provided above, increasing velocity also increases effective range.  (Since there is no standard for calculating "effective range", each shooter is free to decide for themselves what the determining criteria will be -- meaning mine is as good as any.)

Let's take my North Fork 350g .45-70 load as an example, using muzzle velocities of 1750fps and 2183fps, with the rifle sighted in for MPBR at each velocity.  Since retained energy is not an issue, we will allso use my definition of "effective range":  the maximum range at which the bullet never deviates more than +3" or -12" from point of aim.
 

Code: [Select]

North Fork 350g Bonded FP
Muzzle Velocity             1750fps             2183fps
100 Yards                    +2.8"               +3.0"
Zero                       143 Yards           174 Yards (+31 yards)
MPBR (-3")                 167 Yards           204 Yards (+37 yards)
Effective Range (-12")     215 Yards           260 Yards (+45 yards)

As you can see, increasing the pressure (and hence velocity) adds yardage to Maximum Point Blank Range -- but it adds even more yardage to "effective range" in this instance.

[John A]

This is e very interesting topic and one that has been debated alot on the old marlin site. As far as the tests P.O did with the Win 94 in 30-30 Improved, it was done to show that bolt thrust was less with an improved case with minimal taper! I saw first hand a catastrophic failure of a 95 a few years back and the bolt held in place. The chamber split blowing the forearm off and bending the mag tube down and out of the frame at a 90 deg angle, the frame split down through the scope base holes but the bolt held in place and the shooter was shaken but okay! He was using small charges of Unique and we think he double or triple charged a round.

 I know folks enjoy debates but damn this one is old and I don't think anyone will ever be completely satisfied with the answers. I personally don't get to worried about running the pressures up on the marlin as I'm shooting a wildcat based on the 450 case and using ballistic software it looks like I'm over 50,000 cup and to date with two 95's in this wildcat no problems. I talk to Mic McPherson on a regular base and go with his experience and I don't worry much about it.


John Anderson
www.rockislandballistics.com

John A:

Would this be a 40cal wildcat,or a 35 cal??? I would be most interested in hearing/seeing something this myself.

Mac

 My wildcat is known as the 400 Yukon and is .408 groove, 400 bore! It will push a 265gr Hard cast bullet over 2600fps and is my idea of the perfect elk cartridge in a Marlin lever gun.

 John Anderson
www.rockislandballistics.com

[jaycocreek]

Each time this has been debated,I have learned something new.From Wild West Guns to John A. and his wildcat and the ones that failed.Data from a Responsible web page and a Manufacturer than go over the 40,000 Mark.

It may be old but it still provides some good point's from those that have not posted on it before.

Just my opinion.Jayco.

[CEJ1895]

jaycocreek - man you still know how to stir things up don't ya!  :-D I feel like I've been transported 2 months back in time to the not lamented M/T! :lol: Hey jaycocreek, maybe you can get Buckskinner to join us on the Bigfoot thread a couple of forums down from here! I missed this!    CEJ..

[jaycocreek]

Beam me up Scotty..Sorry,it really interest me and the input get's better as you go.

But me myself would never intentionally go over the 40,000 CUP .It is good to know there is some lee way as mistakes do happen reloading.I have seen 550 grain bullet's go 1679 fps without any sign's of pressure.Yikes,I dumped two I wouldn't shoot after seeing it still rise in velocity.

Best of luck.Jayco

[James B]

All I know is that the Hornady manual says its loads for the Marlin are kept to 40,000 . Thats the loads I use for big game. Black Bears and such.