Brand new to these 45-75 LARGE bullets

[Fred T]

Gents,
I am new here but a long time loader and shooter. My son and I are looking for some reasonable starting loads to go in a Perdosoli 45-70. We are hoping to try 500 meters this summer at Ben Avery. At any rate the bullet is a ~500 Posun? I am looking for something around 1150 or maybe less. I don't have nor can I find reloader 7. I DO have 4895, 4831 H1000, N310, bullseye, green dot, unique.....and would like some safe starting ideas. The manuals I have done have much in them that pertains to these billet weights?

Thanks a bunch
Fred T

[RickinTN]

Wait 'til someone else comes along with experience with a heavy bullet but 11 to 13 grains of Unique sounds about right to me. Post here and let us know your results.
Take care, and good luck!
Rick

[Fred T]

Thank you, I am thinking about a light load of something and a wad of Dacron to take up the airspace and see what happens. In researching all this i find recipes for a "duplex"....sheesh all my life all I have ever heard is DONT MIX POWDERS! now there are recipes for a "mix" ugh... whats an old man to do...
Fred

[1Hawkeye]

For a 500 gr in a .45-70 try 12.5grs of unique with NO fillers and that should put you at the same velocity as the original bp load.

[BLAHUT]

12.5 gr unique under a 500-gr bullet in a 45/70 will get you about 1180 FPS. 42 grs of blackhorn209 under a 500 gr bullet in a 45/70 will get you about 1200FPS depending on lot, 27 grs of 5744 under a 500-gr bullet in a 45/70 falls in the trapdoor range. If you use blackhorn209 no air space in cartridge, use wads as filler.

[Harter66]

I forget the charge but Ken Waters tried 4350 and 4831 in 45-70 .
The CIP standard is 31kpsi while SAAMI is 28kpsi .
He states that 4831 delivered better accuracy than 4350 . At the time I was reading it struck me as being a full case not compressed under a 405 . Neither burned clean or completely. I have a history with 4350 and can say that his description placed those loads under 30kpsi probably closer to 26kpsi . Of course how much occupies a full case to the base depends heavily on the arm and bullet . A 45-500 SP has a lot less bullet in the case than the FP . Loaded out to the top grease groove the 458132 at 535 gr has less bullet in the case than the Marlin length 458193 at 405 gr . The 462-420 MP@ 417gr has less bullet in the case than my 458193 at 415 gr and the same 2.55 OAL .

When you find data at 35 gr for the 45-500 FP and 45 gr for 45-500 SP it's because there's 3/8" less case occupied. The length doesn't matter in a single shot as much as a lever .

[Fred T]

So a brief update,
We did load five rounds each of 12 grns, 13 grns and 14 grns of Unique. None of them exhibited ANY pressure signs, we are off to the range this morning to do a do doppler speed check and see where we are velocity wise. Next question will be one of lubrication. I am thinking about powder coating the bullets rather than the wax lube we are currently using, it makes a mess and is difficult to get out of the barrel.
Stay Tuned
Fred

[Fred T]

So it looks like 14.0 of Unique gave the most consistent results. Only five shots were fired and properly recorded but the velocity range was 1065-1085. Im not sure how the temperature effected things other than the shooter, it was about 27 deg F here in Ohio this morning. The Lab Radar had some issues also operator induced....My next move will be powder coated boolits with 15 gns and then some with 16 gns to see what happens. Im Looking for about 1100-1200 fps.

Fred

[RickinTN]

Thank you, I am thinking about a light load of something and a wad of Dacron to take up the airspace and see what happens. In researching all this i find recipes for a "duplex"....sheesh all my life all I have ever heard is DONT MIX POWDERS! now there are recipes for a "mix" ugh... whats an old man to do...
Fred

No "Wads" nor any fillers is what I would do. Would hate to ruin a good rifle.
Rick

[JSnover]

So a brief update,
We did load five rounds each of 12 grns, 13 grns and 14 grns of Unique. None of them exhibited ANY pressure signs, we are off to the range this morning to do a do doppler speed check and see where we are velocity wise. Next question will be one of lubrication. I am thinking about powder coating the bullets rather than the wax lube we are currently using, it makes a mess and is difficult to get out of the barrel.
Stay Tuned
Fred

What type of wax lube are you using? All the home brew lubes I've tried had a minimum 40% beeswax content and none of them were difficult to clean.

[Fred T]

Gents,
An update, I have decided to use a powder coated bullet and through my testing, the powder coating robs about 35 fps from the original wax lubed bullet, I am willing to give that up for the powder coated bullet tho. I have worked my way up to 16 grains of Unique and maxing out at about 1185fps. Then I decided to try some 4198, it turns out 31 grains will put me right around the 1200fps mark and that is what I am trying to achieve. According to what little documentation I have, 16 gns of unique is maximum however the 31 grains of 4198 is about middle of the road. I like the full case idea as well, the 16 grains of unique makes me uncomfortable with the large airspace behind the boolit. Neither of these loads exhibit any signs of pressure and both are very comfortable to shoot.
Good Shooting to All,
Merry Christmas
Fred

[405grain]

Fred T: Flake type double based powders like Unique have properties that you should be aware of. First, because of the nitroglycerin/nitrocellulose mixture, coupled with the large surface area of the individual powder flakes, these types of powders are easy to ignite. Fillers are usually used with slower burning powders to keep the powder charge back near the primer flash hole for more uniform ignition. Fillers are not necessary with unique, and the air space behind the bullet when using this powder is of little consequence. It is not advisable to use a filler with most fast burning pistol powders. Before attempting to use a filler of any type you should read up on the technique. Do not pack a filler down tightly on top of the powder charge leaving an air gap between the filler and the base of the bullet. Doing this is dangerous and could potentially damage your rifle. A properly used filler with a slower burning rifle powder is both safe, and can improve accuracy.

Smokeless powders are designed to work within a certain range of pressure. As a general rule, once those pressures approach the peak in that particular powders range the pressures can start increasing much more rapidly than they do in the middle of that powders range. This is especially true with the faster burning pistol powders. Don't try to push loads with unique in an attempt to gain higher velocities because, as you near those velocities, the pressure will increase dramatically. With the lower velocities like you have been shooting unique is perfectly safe. But for velocities of 1300 fps and up you'd be much better served by using slower burning rate powders. IMR-4198 and Reloader #7 are both good choices for "Trapdoor" level loads in 45-70. (no fillers required)

Duplex loads: (using a small charge of fast burning smokeless powder at the base of a full case of black powder) This is usually used by more experienced reloaders as a way to get a cleaner and more complete burn with a black powder charge. Quite often these type loads are used by competitive target shooters who are quite knowledgeable in what they're doing. I wouldn't recommend trying this unless you're an experienced and skilled reloader that's confident with this type of load.

[indian joe]

Thank you, I am thinking about a light load of something and a wad of Dacron to take up the airspace and see what happens. In researching all this i find recipes for a "duplex"....sheesh all my life all I have ever heard is DONT MIX POWDERS! now there are recipes for a "mix" ugh... whats an old man to do...
Fred

Fred
duplexing BLACKPOWDER with a ten% kicker of medium smokeless (4227 is ideal) is a good tactic - works well - runs clean between shots - been done plenty without negative results . Its not a mix!!! the smokeless (6-7 grains) goes down on the primer then fill case with BP - need enough compression on the load to keep em where ya put em.
Duplexing two kinds of smokeless ? not my game -----------

[StrawHat]

The original duplex load was a pinch 3-5 grains of black under the harder to ignite smokeless powders of the day.

Kevin

[Sgt H]

Fred where did you get the 16 grains of Unique load with a 500 grain boolit? I would be very leery of this as my info suggests that load is near the 40,000psi level. Even 14 grains is going to be close to 30,000 psi. I burn quite a bit of Unique in 45/70 loads but don't go over 14-15 grains with 300-400 grain boolits.