long winded question about powder weights

[Scibaer]

here's what my Hodgdon book says for a 45-70 trapdoor load.
 300 gr. hp ----- H4198 ----- 55.0 gr. ----- 2221 vel. ----- 27,6 K cup

1. this is the max powder load ( 55 grains ) for this load ?
2. what would be the minimum grains to start with ?
3. how does ( a newbie like me ) guage a start point for any given load ?
4. this load requires a Sierra bullet, if a Hornady bullet of the same weight is used, should the charge thrown be reduced even more ?

[John Traveler]

I would do a recheck on your load weight data!

That 55 grain charge of H4198 is listed as a MAXIMUM RUGER LEVEL .45-70 load in my Hornady Handbook of Cartridge Reloading Volume II.

It is NOT a "trapdoor level" load.

[Coyote Hunter]

I would do a recheck on your load weight data!

That 55 grain charge of H4198 is listed as a MAXIMUM RUGER LEVEL .45-70 load in my Hornady Handbook of Cartridge Reloading Volume II.

It is NOT a "trapdoor level" load.

Actually Hodgdon lists that load in their 2004, 2006 and 2007 Annual Manual data.  Maximum for a Marlin is listed at 60.0g (2424fps, 40,000 CUP) and 'Modern rifles' at 63.0g (2532fps, 50,000 CUP).


My chrono data (22" Marlin) shows 2247fps using Staline grass, Speer 300g Uni-Cor bullets and 54.5g H4198.

To answer the original question, starting data is as follows:

45.0g, 1807fps, 16,700 CUP, Trap Door
55.0g, 2221fps, 27,600 CUP, Marlin  24"
59.5g, 2394fps, 37,300 CUP, 'Modern Actions'
The listed starting data is

[Scibaer]

well my questions still stand, however one manual shows H4198 ----- 42.3 --- 44.6 ---- 46.8 --- 49.0  ---- 51.2 ( max ) listed for marlin levels.

the other manual ( hodgdon powders ) shows   ............H4198 ----- 55.0
                                                                               H322 ---- 60.0
                                                                               Benchmark -- 63.5 compressed
                                                                               H4895 ------ 62.0 compressed
                                                                               H335 --- 63.5
                                                                               varget --- 63.0 compressed
i have not made a typo, this is how it reads. for the 45-70 gov. trapdoor loads. marlin or ruger levels are not listed. this book came with my Lee kit.
Lee Data Manual for Hodgdon Powders.
i have a Loadbooks One Book One Caliber manual, its shows trapdoor loads a low of 26.9 ( Viht Powders ) to a high of 54.0 ( H322 )
this is the reasons for the forementioned questions..

[Coyote Hunter]

here's what my Hodgdon book says for a 45-70 trapdoor load.
 300 gr. hp ----- H4198 ----- 55.0 gr. ----- 2221 vel. ----- 27,6 K cup

1. this is the max powder load ( 55 grains ) for this load ?

That IS the maximum load – for Trapdoor rifles.

2. what would be the minimum grains to start with ?

Here are the starting and maximum loads for H4198 per Hodgdon:
Trapdoor – 300g Sierra, 24” barrel, WW case, CCI 200 primer
Start:  H4198 – 45.0g, 1807fps, 16,700 CUP
Max:  H4198 – 55.0g, 2221fps, 27,600 CUP

Marlin – 300g Sierra, 24” barrel, WW case, CCI 200 primer
Start:  H4198 – 55.0g, 2221fps, 27,600 CUP
Max:  H4198 - 60.0g, 2424fps, 40,000 CUP

Modern Firearms
Start:  H4198 – 59.5g, 2394fps, 37,300 CUP
Max:  H4198 – 63.0g, 2532fps, 50,000 CUP

3. how does ( a newbie like me ) guage a start point for any given load ?

The best way is to have several reliable data sources available.  Know that even the best sources often contain errors and make your decision accordingly.  My preference is data that includes actual pressures.

4. this load requires a Sierra bullet, if a Hornady bullet of the same weight is used, should the charge thrown be reduced even more ?

The load data you posted is MAXIMUM for Trapdoor rifles.  MAXIMUM is NEVER a good place to start.  If you are loading for a Marlin or ‘Modern Firearm’ (like a Ruger #1) choose your starting loads accordingly. 

Lower charge weights IF USING STARTING DATA but different components?  Generally, no, but in some cases, yes – if, for example, the components are dramatically different in a way that might increase pressures.  For example, the 350g North Fork is considerably longer than a 350g Hornady and, when loaded to the same COL, the North Fork load will have significantly less powder space. 

That said, there is often a point at which further reduction is not advised by the powder manufacturers.  Generally speaking, a 10% reduction for MAXIMUM loads is a reasonable starting load.  With powders like H110, though, a 5% reduction or less is recommended.  (Not that you would use H110 in a .45-70.)

[Scibaer]

ok, having read that a few times, i think i understand. once i understand the load data, its common sense really.
cross references will help eliminate printing errors, and knowning whats safe for my rifle will set my limits.
thanks for taking the time to answer my questions, coyote hunter. i know that took a bit of effort and i appreciate it
 and it makes sense, that if the bullet is very similar in weight and dimentions, the load will have a better chance of being ok, then if the bullets are alot different .

a question about primers. how do i measure primers, not for size, but for how hot they burn, are they rated ?

[stimpylu32]

Glenn

As far as primers they come in 2 classes , standard and Mag ( mag being hotter ) . that being said there are some diffrences in both classes , for example the Federal's tend to be softer than the CCI's so in guns that have a light pin strike the Feds tend to work better .

Also some powders will need the hotter mag primers to get a consistent burn , H110 & win 296 are prime examples along with some Ball powders .

stimpy

[Scibaer]

my Lee auto prime says not to use federal primers because they are soft and could go off in the primer.
so, if the load data asks for a specific primer, then i should use them, knowning some basic info about the 'personality' of some primers like Fed's.
ok, so its not all that complicated or difficult.
you know, the more i read, the more questions i have, lol .. am i learning or getting dumber ? l
thanks, stimpy

[stimpylu32]

Glenn

Ya Lee says not to use Feds in the auto prime , that being said i have seated 10,000s with mine . ( Rule # 1 --- ALWAYS--- wear safety glasses while working with primers ) .

For the new handloader it is best to stick with the componates that are listed for a given load , the down side is that you will end up with a dozen diffrent brands of primers or is that the up side . 

Since your be loading for the BC in 45/70 , the CCI # 200 LR primers would be a good choice .

stimpy

[Scibaer]

Up side for sure 
 that's my intention, to follow the given load data. im not going to experiment 'too' much.
i'm looking to shoot more, and reloading should allow me to do that, but i have every intention to hunt with my BC.
so the loads i work up will be for hunting.
i guess i need to get me some CCI primers then. and maybe a few.. and some.. just to be safe i'll get 
glenn <--- turns sons room into reloading and gun room <--- wife sends Glenn to doghouse,