Translating a 777 load to a BH 209 load

[BlackPowderGuy (AJHS)]

Given prices, I want to use 777 to build a load and use BH 209 when actually hunting. Would you expect the following procedure to work. Since I don't own a chronograph, use published load data to find the muzzle velocity of 777 for a given bullet and the muzzle velocity of the same bullet with BH 209. You would expect the point of impact to be fairly close as you moved between them, right?

For example, if 100 grains of 777 FFg will move a Barnes 290 TEZ at 1800 FPS, and 83 grains of BH 209 will also move that same projectile at the same speed, then wouldn't you expect the bullet to hit in the same place?

 

[michiganmuzzy]

Based on what ive heard and read, yes a ffg T7 100 grains should be pretty close to the same velocity. And the pressure curves look very close too so yes they ought to be same poi. But as you know theres only one way to be sure.

 

[Ninering62]

Given prices, I want to use 777 to build a load and use BH 209 when actually hunting. Would you expect the following procedure to work. Since I don't own a chronograph, use published load data to find the muzzle velocity of 777 for a given bullet and the muzzle velocity of the same bullet with BH 209. You would expect the point of impact to be fairly close as you moved between them, right?

For example, if 100 grains of 777 FFg will move a Barnes 290 TEZ at 1800 FPS, and 83 grains of BH 209 will also move that same projectile at the same speed, then wouldn't you expect the bullet to hit in the same place?

It really doesn't need to get all that complicated, Fire the bullet you use with the BH 209 charge you use at a target at the range you use. Then switch powder to T7 & adjust your charge up to where your bullet POI is the same as your BH 209 charge. No chrony or anything else needed.

 

[ronlaughlin]

A 250g Blue Diamond bullet shot using 81g weighed 777ff was clocked here at 1960 fps.

A 250g Blue Diamond bullet shot using 81g weighed Blackhorn was clocked at 2020 fps.


For hunting we used a Blue Diamond bullet with a load of 76g weighed Blackhorn, after sighting in using the 777ff. Final sight adjustment didn't take much.

 

[txhunter58]

I have never had any luck switching from one powder to another and having the same exact POI. But why would you need to in what you are trying to do?

Get your BH load dialed in. Then try 777 powder adjustments during practice to get close to your BH POI. Let’s say the 777 hits 1” up and 1” to the right of the BH. It doesn’t really matter that your POI is slightly different at the range as long as you are consistent.

Also, at what distance? The 2 loads could be dead on at 50 but they will prob be slightly different at 100, 150….

Get your BH load dialed in. Then try 777 powder adjustments during practice to get close to your BH POI. Let’s say the 777 hits 1” up and 1” to the right of the BH. It doesn’t really matter that your POI is slightly different at the range as long as both groups are consistent.

Right before you head to hunt, fire a couple shots of BH to be sure you are still good