My current 470 load is 89 Grains of RL 15 with a foam wad pushing a 500 Grain Woody at 2100 FPS.

If I drop my powder charge to 67 Grains (75%)

1)Will it by safe to shoot in my Krieghoff?
2)What would be an approximate velocity?

Thanks

If you're talking about N E 450 #2 (Tonys) 75% rule, you're going the wrong direction. It's full charge of powder and 75% weight of the bullet.
Here's a copy and paste of his rule.

"The 75% rule:
You take a bullet, that is 75% the weight [as close as you can get], to the bullet that is the standard load for your Nitro Double.

Then you use the SAME powder charge as your normal load.

You might have to adjust up or down a couple of grains.

The result is a load that is better suited to smaller game, that will regulate and hit to the sights.

Because the bullet is lighter, [and the powder charge the same] recoil will be reduced.

In testing out to 200 yards in my 450 No2, and to 300 yards in my 450/400 3 1/4", the trajectory is the same for the full power/weight load and the 75% load.


In testing Nitro for Black loads, I have been able to find loads that regulate well and will hit to the sights at 50 yards.

They still shoot good at 100, but because of their reduced velocity they do not have the same trajectory as the full power loads."

Actually I built a box to test penetration for solids. 2100-2150 is what I consider "standard" velocity for the nitros.

I want to slow a bullet down to around 1700FPS and test penetration.

Woodys will be the first bullets tested. Northforks afterwards.

less powder more foam wads?

quote:

Originally posted by Will:
less powder more foam wads?

Sounds almost too simple.

It should cause less pressure, just want to make sure. If it was a bolt gun I would be less hesitant.

Are we talking those soft gray foam ones? Like the foam they use to cushion delicate electronic parts in shipment? In my competitive Schuetzen days I used the Oasis crinkle foam florists use for flower arrangements. Just cut 1/8th inch thick by 1/2inch wide strips and pushed them over the case mouth. Worked great.

Rich

Mike Brooks

You have stated my 75% rule properly.

Mike 70560 Do not drop your powder charge...

I did a copy and paste from your old posts telling about it.. That way it's right,w/o a doubt!

Let me restate the question

Does anybody have a load for a 470 Nitro that would push a 500 Grain Woody at about 1700 FPS

I am NOT worried about regulation. I am NOT referring to the 75% rule. I AM concerned about pressure in my double.

Mike I sent you a pm,did you get it. There was a article on African hunter site on reloading cast bullets in the 470, the link does not work any more. He loaded 45 - 55 grs of 5744 and at the 55 gr load was near there. I shot 5744 with good results with both cast and jacked bullets, the 55 gr load has a little kick and would kill any thing that walks here. Do not use spacers with 5744 per the factory rep!!! Its made to work in case of large volume and air space,The spacers will cause a problem with this powder.
The hornady pistol bullet also shoots good, you need to keep the load at pistol fps it was designed to work at.

I got good groups with 5744, it shot several inch's low, I need to make some spacers for my peep sight and I be good to go with it.


JD

JD:

What bullet weight did he/you use with the 45-55 grain load of AA5744?

500 gr cast with gas ck, 370 hard cast with gas ck,hornaday xtp pistol in.475 dia. (I don't remenber what they weight). I got good groups with all of the above. I shot some full power loads with RL 19 with both cast bullets and had some good groups. I was useing a little pufflon to fill the little air gap and protect the base of the bullet. The 370 gr bullet is close to tonys 75%.

JD