With the 45-70 in a Marlin 1895gs, 40K pressure is the max. This isn't enough to cause any primer deformation or flattening, or do anything to the case. How do I tell when I have a max load, before filling my face with shrapnel? So far I have been really cautious, but I would like to work up if possible.

There is only one way - PRE. You would want to follow the PRE portion of these Instructions.

CHE will not work because the Pressure is too low. And using a Chronograph won't work because it doesn't tell you anything about Pressure.

You must follow the Instructions - exactly - and use a 0.0001" capable Micrometer as directed. Anyone can do it just as it has been done Safely for well over 100years.

Best of luck to you.

Joe D'Alessandro at realguns has written some articles about getting the right pressure handloads for his Marlin 45/70 1895 guide gun:

http://www.realguns.com/archives/036.htm
http://www.realguns.com/archives/037.htm
http://www.realguns.com/archives/038.htm
http://www.realguns.com/archives/052.htm
http://www.realguns.com/loads/4570.htm
http://www.realguns.com/archives/073.htm
http://www.realguns.com/archives/074.htm
http://www.realguns.com/archives/069.htm
http://www.realguns.com/archives/117.htm

Thanks!

quote:

Originally posted by Hot Core:
There is only one way - PRE. You would want to follow the PRE portion of these Instructions.
CHE will not work because the Pressure is too low. And using a Chronograph won't work because it doesn't tell you anything about Pressure.

You must follow the Instructions - exactly - and use a 0.0001" capable Micrometer as directed. Anyone can do it just as it has been done Safely for well over 100years.

Best of luck to you.

While this might work using Buffalo Bore or Grizzly 45-70 ammunition, which is the only commercial ammunition available that approaches the maximum average pressure of 40,000 CUP, with the method described by Hot Core, there are problems extending that methodology to new brass. Neither company makes the brass they use available to reloaders as new brass. So, using Hot Core's method you would be limited to using the fired brass from either Buffalo Bore or Grizzly ammunition. How many firings, from which the brass changes from its virgin state, will it take to make such measurements unreliable?

Mic McPherson came up with a way to develop maximum loads for Marlin lever guns chambered with straight-walled (slightly tapered) cartridges in a 1994 Handloaders Digest article. PM me if you want the gist of it.

Sent you a pm.

easy. use IMR 3031 and a chronograph. it's pressures are low enough that the chrono will keep you out of trouble.

I get 1800 fps with a sub-max load with 400-gr bullets. the pressure for the max load is 27,000. way below 40,000.

Or get 2400fps with H4198 @ 40k with 300 grainers. Flattens trajectory a bit.

My 4th Edition of the Hornady Reloading Manual has specific loading data for the 1895. I would follow that data. I don't know if the new manual has the 1895 data or not.

The 48th Edition of the Lyman reloading manual also has data specific to the 1895 and their pressure readings are kept around 25000 C.U.P.

There are two manuals that would allow you to cross reference your prospective loads.

quote:

Originally posted by jackfish:
...with the method described by Hot Core, there are problems extending that methodology to new brass.

I agree with jackfish that there are some Tricks to this. Fortunately that is covered in the Instructions.

quote:

using Hot Core's method you would be limited to using the fired brass from either Buffalo Bore or Grizzly ammunition.

That is a common misperception, but simply incorrect.

quote:

How many firings, from which the brass changes from its virgin state, will it take to make such measurements unreliable?

That is also covered for those of you who might be interested.

Best of luck to you all.

quote:

Originally posted by Hot Core:
That is a common misperception, but simply incorrect.

You missed my point completely. The reloader cannot obtain new brass that is equivalent to the brass used in the Buffalo Bore and Grizzly ammunition.

quote:

Originally posted by jackfish:

quote:

Originally posted by Hot Core:
That is a common misperception, but simply incorrect.

You missed my point completely. The reloader cannot obtain new brass that is equivalent to the brass used in the Buffalo Bore and Grizzly ammunition.

Actually, I understand that and did not say it well at all.

Once you use the Buffalo Bore Factory Ammo to establish a Comparable Benchmark Standard(CBS), then you reuse those same Cases to Develop your Loads in.

Once the Safe Max Load is known, you can easily work the Load back up in other Cases - while still watching CHE & PRE for Excessive Pressure "Indications". I agree there are some small tricks to it, but CHE & PRE simply works.
-----

Try it and you can see for yourself. Once you get past the incorrect notion that it won't work and actually follow the Instructions, you can see for yourself how well it works. Then you will see how badly you have been mislead by folks who just don't understand Basic Reloading.

Best of luck to you.