6BRA load data

[BartsBullets]

Yup. Measured with a lab radar over two range trips. This lot is faster than my last "good lot" of H4895. My last good lot would have #s like you state.
30.5--2,964fps
31.2--3,028fps No pressure. 100FB reamer

Cool that’s probably not a lot different then what I’m seeing here in The Heat!

Early in the year 30.5 was giving me around 2920. Now 30.8 is getting over 3000.
Bart

 

[Link]

So now I'm confused. If I shot 1 shot of each powder charge 3 times it would have been all screwed up. Now with the overlap of shots how can a 1 charge ladder work? Does that make sence ?

 

[Dave Way]

So now I'm confused. If I shot 1 shot of each powder charge 3 times it would have been all screwed up. Now with the overlap of shots how can a 1 charge ladder work? Does that make sence ?

Assuming you are testing in ideal conditions, a multiple shot ladder should give you more confidence in your data. In addition it can tell you more about where the ladder flattens out because you can see the shape of the groups. In my photo which you re-posted, you can see that with 30.7 and 30.8 grains, the load and group shape flattened out.

One shot with each of those two charges would have worked, only because that happens to be where the rifle “flattens out”. One shot with the other lighter charges could have left you wondering or worse yet assuming, or chasing something that just wasn’t true.

I hope that explanation helps.

Dave.

 

[Nature Boy]

I use the Cortina method at 100 yards, but recently compared it to a ladder at 500 just to see if they complemented each other.

Here’s the 100 yard target, the number to the right of the dot is the distance from POA

Group centers from POA are consistent from 30.4 to 31.0. FPS flattens out between 30.7 and 31.0. I select 30.8 as my load

Here are the same charge weights shot at 500 yards. It supports the node being between 30.7 and 31.0

Subsequently, I’ve shot the 30.8 load in two 600 yard F Class matches and scored 600-36X and 597-31X, respectively.

I’m done tinkering with it

 

[JFrank]

^^
Interesting that .3 gr difference had the same FPS

 

[Nature Boy]

^^
Interesting that .3 gr difference had the same FPS

According to Erik Cortina, a flattening out of the FPS between charges is another indicator of the accuracy node. Can’t get any flatter than 0

 

[JFrank]

According to Erik Cortina, a flattening out of the FPS between charges is another indicator of the accuracy node. Can’t get any flatter than 0

I get that it’s just that ya normally don’t see -0- accompanying a bit of vertical on paper. I would expect side by side poi

 

[Nature Boy]

I get that it’s just that ya normally don’t see -0- accompanying a bit of vertical on paper. I would expect side by side poi

Ahhh, I see. These were the averages of the 3 shots on the 100 yard target

 

[Link]

Here's another 1k test with ol roys... View attachment 1116373

Can you tell us what the charge weight was?
thanks

 

[urbanrifleman]

Has anyone got any data for r15?

 

[ledward]

With my current lot of RL-15
32.2-.3 in two barrels 2985fps
one other barrel runs 32.7 @ 2955FPS
.125" freebore

 

[10at6]

31.8 RL-15 with 108 Bergers 2945 FPS. Wolf SRM primers

 

[greisdor]

How about using IMR4895 ?????

 

[Jet]

Recently did a ladder with a new lot of H4895 and VLDs and had nodes at both 30.5 and 31.2. Will test in a week at 600 to see which one shoots better. More to follow.

Rich

Shot both powder charges today at 600 and 30.5 shot a bit flatter. 31.2 had light ejector marks on the brass.

 

[BartsBullets]

How about using IMR4895 ?????

It’s too slowwwwwww!

Bart

 

[greisdor]

May be a mistake but goin to see if it will group - this Brux Barrel has shot just about everything I loaded in it. Using Vapor Trails and Hammers, H4895,RL15,N140,N150 and N530.

Jerry

 

[BartsBullets]

May be a mistake but goin to see if it will group - this Brux Barrel has shot just about everything I loaded in it. Using Vapor Trails and Hammers, H4895,RL15,N140,N150 and N530.

Jerry

Keep us posted and take your chronograph!

Bart

 

[JohnMill]

But no N540. The only Vihta powder I've seen cited as superior in the 6BRA, but I could not find it(the recommendation)again and I did not find it (the powder) so. I've been hoping because I like VV powder.

 

[Nature Boy]

VV140 or VV150?

 

[JamesnTN]

It’s too slowwwwwww!

Bart

Bart according to hogdon website H4895 is 89 and IMR is 91 on burn rate chart. So how’s IMR 4895 too slow?