Okay, I've got my order in for the eaa mp221 45/70 deluxe elcheapo double rifle. $539, on pre-order... but these guys want 1/2 down..so I didn't order through them. I am still expecting 100 days till i get it

http://www.marksmansmart.com/prodDescription.asp?catID=22&subCatID=442&prodID=60838

Anyway, I am sitting here thinking, what can I do to get some neato ballistic and not totally rework the gun.. and BAM! it hits me

make a 458lott FLANGED!!!

Take the 375 flanged, take some taper out, neck to 45, and run at 30-35kpsi...
<or just use 45 basic brass>..<45 basic jeffe>
Case head OUGHT to be identical and case capacity ought to be in the 105 range

quickload (using the lott case, with a 35000 PSI ceiling 400gr rem) says 2250 with 400 grains vs 1850 in a 45/70 at 35k.... and 2000 fps in a 45/90

hmmmm

this could mean just reaming the chambers, not messing with the extractors, not overly thining the barrels, and having a low pressure 450, that doesn't use a huge case.

My concern on the case is that this action looks like a 410 or 20 ga action, and the spacing/width between barrels could become critical.

Just some musings of mine...

oh, yeah, 500 at 1997fps...

sure sounds like a low pressure, easy extracting winner...

thoughts?

btw, the unformed 375 flanged looks perfect but the 45 basic is perdactly the same??

jeffe

anyone got a reamer for "45 basic jeffe"

[ 07-03-2003, 05:43: Message edited by: jeffeosso ]

Jeffe:
Just a suggestion...why not use 45 Basic brass since it is the same rim as the 45-70. It is 3 1/4 in length and you could leave it full length or cut it to any length you want. Probably get away with using 45-70 dies also...Just thinking, although that could be dangerous!

CM,
I was researching that... thinking can be dangerous.... for me, at least

the 2.6" would cost less(1/2 as much) and NOT present loading issues if the action doesn't liek 3.25,,,,

jeffe

[ 07-03-2003, 05:45: Message edited by: jeffeosso ]

Not that I know what I'm talking about, but I think the 45 basic would be the best. Same rim, same extractor, load data for 45-120, just ream and go.

jeffe, why not just go to the 45-110, you can get brass from Star line

gee's thanks Mac!!

458 jeffe... not rcbs... oh well... live and learn... might be nice to get 450 ne without huge ca$e$

at least i might can rent the reamer when i get bored with getting wopped with a 45/70 at 7.5

Sounds interesting....

The 458 RCBS does have smaller dimentions in the rim and base dimentions than the 45/70 - so it wouldn't clean up the chamber at the base and rim (by a few houndreds).

What about the 45-90 to 45-120?
What kind of performance and pressures can you get from the? 500grn at 2150fps?

Franz

[ 07-04-2003, 16:04: Message edited by: Daydreamer ]

See there! There is no room left for the thinking man in the wonderful world of wildcatting, its done been done!!

thanks for the kinda support Ray...

Look like it's going to be 45/120 for me...

anyone, other than hand ream job axel, got load data?

jeffe

jeffe,in mine I use the following

715 gain cast lead
112 grains FFG swiss black
one card wad and one wonder wad
bertam brass and winchest mag primer
Or you can try 95 grains 4831 and a 400 grain Barnes X bullet

[ 07-10-2003, 09:52: Message edited by: Dave James ]

Anyone an idea what the 45-70 Elko Magnum is?

Found specs for it at Lothar Walthers HP showing same case dimentions but 50% higher pressure.

Wonder what it is....

Franz

Nother question:

Will the standard twist of the 45-70 barrels (1:20) stabilize a heavier bullet at higher velocity?

The standard for the 458WM is 1:14 or 1:16 but some propose a 1:12 to (over?) stabilize the bullet to prevent failures (tumbling bullet) at close range hunting DG...

Does a lighter/shorter bullet that is travelling faster need slower or faster twist?

Just don't want to see someone getting mauled with a converted 45/70.... but am very interested if this new rifle can be used with more power!

Franz

What about the Pedersoli 45-70 doubles that were converted to 450 no2? what twist did they use in the original barrels? I haven't heard anything bad about them.

Load data at www.hodgdon.com
http://www.hodgdon.com/data/cowboy/lrrd.php#45-120
Sharps 45-120
350 GR. LYMAN #457122

H4895

59.0 gr.

1875 fps

24,800 cup

64.0 gr.

2031

26,900

Benchmark

53.0 gr.

1809

24,700

57.0 gr.

1922

26,800

H322

50.0 gr.

1717

21,000

53.0 gr.

1874

27,700

H4198
46.0 gr. 1783 22,500 49.0 gr. 1903 27,500

45-120 Sharps
405 GR. LYMAN #457193

Varget

59.0 gr.

1763

24,200

63.0 gr.

1858

28,200

H4895

58.0 gr.

1849

26,000

64.0 gr.

2012

28,300

Benchmark

53.0 gr.

1805

26,500

58.0 gr.

1917

27,200

H322
49.0 gr. 1665 23,200 52.5 gr. 1793 27,900

H4198

45.0 gr.

1708

24,700

48.0 gr.

1818

27,200

45-120 Sharps
500 GR. LYMAN #457125

Varget

56.0 gr.

1618

24,200

61.0 gr.

1737

27,900

H4895

54.0 gr.

1641

24,400

60.0 gr.

1809

28,500

Benchmark

50.0 gr.

1607

26,600

54.5 gr.

1747

28,200

H322
48.0 gr. 1568 25,400 52.0 gr. 1695 28,300

H4198

42.0 gr.

1523

25,200

46.5 gr.

1650

28,300

[ 07-10-2003, 22:41: Message edited by: Brent ]

I checked the EAA site again and the some double is made in .270 win, which has a max pressure of 65kpsi
so to calculate the bolt thrust gives 11.245kp
now divide by the case area of the 45 case and we get
63kpsi max pressure for a safe bolt thrust.
Now as long as the diameter of the bbl with hold the pressure, you should be able to load in the 45+kpsi range safely without worries and still get easy extraction.

?????????????????????????????????????????????????

AH Brent its just some thing to play with But you should see it drop a hog

Lar45 - your'da man!

I was searching for that kind of information a long time....

I wonder what the figures for bolt thrust are for the .450/400NE 3", .450/400 3 1/4, and the 450NE 3 1/4 are.

Maybe in realtion to the 30/06 or .308?

Most doubles of "lesser" quality (also O/U like the Tikkas 512) are manifactured in the .308 oder 30/06 - so if I knew what the bolt thrust figures are compared to the big low-pressure nitro rounds, I could estimate if the action could possibly be used for a big hammer.

Would you mind to calculate the bolt thrust figures for the 450/400ed's and the 450's 3 1/4 and the #2 3 1/2?

MANY Thanks!

Franz

Thanks all

since the action looks so light, I am worried about 2 things... extractors (don't want the extra work) and barrel wall thickness, as the firing pins would be a critical path item... can't really move those easy.

the pedersoli weighs 10.5 and the eaa is listed at 7.5.. bet the barrels are thin.

I too was thinking that since it's also listed with high pressure rounds that bolt thrust would be the limiting issue for pressure... and had planned for 35k... 45k helps ALOT to get near 450 ne... in fact, i believe the 120 (at 45) could meet or beat the 450 ne....

500 grains at 2150... whew... bet my eaa gets 2# lead in it.

jeffe

To calculate bolt thrust, its pi*r^2*(chamber pressure)
pi 3.14 * (the diameter of the base/2) squared this is the area of the base of the cartrige.
Then multiply by the chamber pressure, this give the bolt thrust.
When looking at a different cartrige on the same action, divide by the new base area to get a max chamber pressure.

Remember, I'm just a guy at a keyboard somewhere, so check everything for yourself.

450-400 3" pressure 16T (40kpsi???)9.28kp thrust?

450 NE pressure 17T (42.5kpsi???)10kp thrust?

450 no 2 pressure 13T (32.5kpsi???) 8.125kp thrust?

470 NE pressure 14T (35kpsi???) 9kp thrust?

For the pressure conversions, I found references to a few different cartriges that had max pressure in tons and psi. It looked like you could multiply the tons by 2.5-2.6 to get a similar number in kpsi. This is probably not accurate in anyway, but it looks like a rough estimate and seems about resonable.

So this is my best guess.

The 270 and 45-120 are published numbers though.

Jeffe, there is an aritcle in my book on building double rifles on shotgun actions, that goes through the process of bushing the fireing pins. You might take a look at the fireing pins to see if they are bushed already, probably not. If you have access to a lathe and mill this looks like it would be doable for a measure of safety in the event of a blown primer. If you want, I can scan the pages and send them. email me if you want.

Lar,
PM sent.. thanks.

jeffe

I did not mean to imply that this was "my" book, it was written by W. Ellis Brown, I just have a copy that I've been useing as a reference for my 470 project.
ISBN: 0-9714802-0-6
if anyone is interested.

Be very carefull of mathmatical formulas for figureing bolt thrust. Though they seem to be correct on paper, there are other variables that come into play that this formula does not take into consideration. The most important omitted thing is case shape. The more tapered the case the higher the bolt thrust will be with the same load, in the same volume case with the same weight bullet. The old case designed for double rifles have a lot of streight sided walls to grip the chamber walls, at the milisecond of peak pressure, giveing less so-called bolt thrust, than a smaller rim dia in a tapered case.

Now, the measurment i tons is not 1 ton= 2000 lbs per inch, but is measured in IMP long tons, per sq in. ( 1 IMP ton= 2240 lbs per sq in.) So be carefull that you do not figure your pressures too low, by useing the 2000lb ton.

The weakest point for a double rifle to fail, is in the chamber walls, and the first 3 or 4 inches down the barrels. A barrel set that will take the pressures of the 270 win @ 50,000 psi chamber pressure, would certainly not take the same pressure with a cartridge with a body as big as a 45-120, or a 450 NE 3.25". The so-called bolt thrust is damageing in the long term, for shooting loose, not blow up! I would be leary of doing much to a double rifle that only cost $600, and I would leave this rifle chambered for 45-70 if it were me,and use it with factory loads, or equivilent! But that's not likely either, because I don't think I will be buying one of these any time soon, A double rifle is not the place to try to enhance performance, or shoot for higher pressures, especially in a bargain basement double rifle. $0.02 worth of my opinion, others may do as they see fit!

Hey Mac,
Generally, I agree with you on doubles, or, more to the point, learn from you in them. In this case, however, I'll state that the rifle will simpley be too inexpensive NOT to experiment. The action will hold 30-06/308... and as teh tikka expereince shows, these modern rifles will hold up to some serious shooting. Who's heard a rumor of one coming undone, in any fashion, from the tikka/valmet/eaa OU? I certainly haven't.
The the status of over lawyered rifles, and that eaa has a long history of selling inserts for their shotguns (which is what I antcipate these things are built off) they can't help but be over engineered for the purpose.
In fact, since these are not being offered in 303/30-30 today, I believe that eaa is making a strong statement that these are strong actions....

I work in the computer technology field... and it seems that the most awesome device one would buy for 100K 5-7 years ago has performance levels far below the current entry level, $299 POS that does the same job. In stero gear, what was 2k 2 years ago is now in the discounted bargin bin, and it's features are now the baseline...

What I am driving at is that EAA has made thousands of their izh series shotguns with inserts for high pressure rifles... they see a market to leverage these and their BUTT UGLY ou's... and if that shotgun action, with inserts is lawyerproof enough to sell, you can bet your bottom dollar that the 45/70 will be overbuilt.

I can't see what not to play with one of these... you can easily take a 45/70 and overload it's pressure... but for the same vel. the 45/90 or 45/120 would be greatly LESS.

and, fwiw, Dave Pedersoli only lists his 45/70 at 28k, right? but folks run it to 450 NE (longer case, 35k, etc) in the same rifle...

just rambling.. I can't wait to get one.

jeffe

Jeffe,

Have you given any thought to using the 450 Alaskan?

I used to get 2150 fps average with 67grs of 3031. This was with the 400 gr Speer. With the extra chamber length that could be bored into the EAA, you could seat the slugs out further. The 67gr load wasn't max, so a little more fps could be attained. The 500 grainers could be utilized with this set up. By the way, this was done in a Browning 71, rebored to 450 AK. Don't know the pressure level, but no visable signs of pressure problems. As you are aware I'm sure, the 348 case is rimmed. Should work very well in a sxs.

Will be watching your progress in this adventure.

Roger QSL

Mac, Jeffe

Sorry for my misleading info about the 458 RCBS - you are right it was thousends not hundreds - my fault.

So what can be done with the 458 RCBS case?

What is its performance?

Franz

Roger,
I hadn't thought of it.. till now... I have access to 450 dies.... but i know the limits of that one, on a 71... 400 at 2250 is the max max in it.

the 45/120 is 13gr more water than the 450... and no case forming issues....

i am sending my handirifle in for a 45/70 barrel this week, i think.. and a trigger job.... we'll see what we can do with it... i have often thought of it as teh poor man's ruger...

jeffe

So,
If you take the 45 basic 3.25" you have the 450 Nitro jeffe Flanged....(also 45 120)

500gr woodliegh at a calculated
~2140fps in a 24" barrel and 40k .... 50 fps slower than the 450 NE 3.25...

450 alaskan tops out at 1900 with 500

jeffe

Jeffe,

Have you handeled EAA's sxs 12 gauge. There is a lot of steel at the chamber. Having not seen the new rifle version, I'm assuming the lock up system to be much the same. If this pans out, re-boring to a longer case shouldn't be a problem.

You maybe right as to the 450 AK getting 2250 as I never took it that far. However, that's loading the slugs deep into the case so as to keep the overall length workable for the 71. You should be able to load the slugs out further with a chamber cut deeper into the sxs's heavy steel chamber area.

Your plan of using the 45-120 sounds real good.

I'm not sure firing a 7.5 pound gun loaded with 500 grainers at 2150 would be a fun event.

Good luck with your project, keep us posted.

Roger QSL