6x47 Lapua comparing H4350 vs IMR4451 with 105 Berger Hybrids

[dstoenner]

I had earlier written about my load development with H4350 and had some questions. I am new to this caliber so I don't have any direct experience to guide me. In that first post, I also mentioned that I was going to compare this to IMR4451 so that I had some inclining of what might be an equivalence. I got to take that data yesterday. This is shot at an indoor 100 yard range so except for some colder temps than the 4350 tests a week before they are apples to apples.

First here is the data that I took with H4350.

charge weight, ave velocity, ES, SD, group size
38.0, 3000, 34, 17, .461
38.2, 3013, 29, 12, .550
38.4, 3037, 34, 13, .465
38.6, 3052, 15, 6, .930
38.8, 3053, 9, 4, .712
39.0, 3053, 17, 6, .519

I have read on other posts that 4451 needs as much as .5 gns to be equivalent to H4350. So I adjusted my loads appropriately. This second set of data was taken with the same lot of 105 Hybrids and the seating die was unchanged. Same case lot with CCI-450 primers.

Here is the IMR4451 data

charge weight, ave velocity, ES, SD, group size
38.6, 3022, 16, 6, .412
38.8, 3045, 27, 11, .790
39.0, 3066, 14, 5, .790
39.2, 3076, 10, 4, .980
39.4, 3097, 28, 11, .800
39.6, 3104, 29, 11, .775

For both the H4350 and the IMR4451, none of these loads created hard bolt lift not flattened primers. There is definitely more head room to go for max load in my 30" McGowen 1:7 barrel.

What I see with IMR4451 you have a very narrow window of low ES and SD compared to H4350. looks like 39.1 of IMR4451 would give maybe 3071 with good low numbers. And 38.8 of H4350 would give 3053 with similar numbers for ES and SD. In my case it looks like .3 gn difference with a boost of 18 fps. 4451 looks like a pretty good alternative if I run into H4350 availability issues. Right now I have 12 lbs but that can go pretty quickly.

Do I see this data correctly. Always like to have other eyes and experience give me your thoughts.

David

 

[missed]

Yeah that looks about right, I'm running 4451 as I ran really low on 4350. I found my happy spot at 39.5g

 

[JLR]

I went from h4350 to Reloder 16 in my 6x47, but did run 4451 in my 6.5 Creed after running out of H4350. Seems all 3 powders work well so I just use whichever one I can find.

 

[dstoenner]

I went from h4350 to Reloder 16 in my 6x47, but did run 4451 in my 6.5 Creed after running out of H4350. Seems all 3 powders work well so I just use whichever one I can find.

How did R16 compare to H4350 for a charge weight? Were you able to get similiar velocity?

 

[urbanrifleman]

R16 is about a grain faster.

 

[JLR]

R16 is about a grain faster.

I would agree with this. Seems like r16 fills up the case more as well.

 

[6xcshooter]

about what I found out about 4451, not as accurate. Another thing I've observed is SD and ES doesn't always correlate with accuracy either