OCW test/ questions

[Kevin1990]

Bought a 26in, 6br, 1-8 twist barrel a few months back. fireformed 100 pieces of brass.

Using Hornady 105 BTHP and varget, with CCI 450 primers.

The first picture is from fireforming and just shooting groups at the cardboard with different charge weights.

Questions:
What powder charge would you go with?

This was done jumping the 105s .020 from the lands. I understand every barrel differs, but could I possibly tighten the group up a good deal by playing with seating depth?

Side note. The 29.8gr group I pulled really bad. So I reshot it on a separate sheet of paper. Then cut and pasted it next to the others. The POI was about the same as the rest.


Thanks fellas

Fireforming 5 shot groups


OCW Test 3 shot groups

 

[VA_XTC_Shooter]

29.5

 

[jr600yd]

What he said ^^^^^

 

[mudduck]

29.5 and run seating depth

 

[Kevin1990]

You could look on both sides of 29.8 also, at 30.0 gr it’s starting to split and by 30.2 it’s gone.

I'd really like to go higher in the powder charges but 30.4 was giving me some pretty stiff bolt lift. And at 30.6 I was getting ejector marks and very stiff bolt lift.

 

[rover31]

29.5

 

[Bill Norris]

Test 29.5 & 29.7 gr.