Ocw help

[Dfarmer786]

I shot ocw test today on my 308, I used 168smk, hornady match brass, varget, cci 2 primers and 2.800 OAL.
The target will be hard to see and read but all groups shot low and to the left #6 group hit the #7 bullseye for reference.

Sighter1- 41.4gr
Sighter2- 42.2gr
Sighter3- 43.1gr
#1- 43.9gr 1.608 from center
#2- 44.3gr 1.305 from center
#3- 44.7gr 2.033 from center
#4- 45.1gr 1.903 from center
#5- 45.4gr 2.340 from center
#6- 45.8gr 2.931 from center
#7- 46.2gr 2.432 from center (pressure signs)

Not sure which load will be best.

 

[Dfarmer786]

Also it's a factory rem 700 sps 20"

 

[Bob 964]

I think your node is 3-4-5, with 4 (45. 1gr.) being your OCW.

 

[oldfatguy]

I think your node is 3-4-5, with 4 (45. 1gr.) being your OCW.

Agreed. Now repeat with 45.1 grn and different seating depths.

OFG

 

[Bob 964]

Agreed. Now repeat with 45.1 grn and different seating depths.

OFG

Agreed. I would load 1 group at 0.010" jammed, 1 group at 0.030" jumped, 1 group at 0.060" jumped, 1 group at 0.090" jumped, and a final group loaded at 0.120" jumped.

 

[Sniper Uncle]

Agreed. I would load 1 group at 0.010" jammed, 1 group at 0.030" jumped, 1 group at 0.060" jumped, 1 group at 0.090" jumped, and a final group loaded at 0.120" jumped.

I think you mean 0.001" jammed, 0.003" jump, ....... 0.010" jammed could be in for big trouble!

 

[8nbait]

A lot of guys jam .010 but not sure I would go there either at this stage. Best to develop load from .010 jam and work away from the lands. Regardless, it sounds he needs to be in the mag. I agree that 45.1 looks like a great starting point but I always like to prove it again just to be sure.

 

[Bob 964]

I think you mean 0.001" jammed, 0.003" jump, ....... 0.010" jammed could be in for big trouble!

No. I said what I meant and I meant what I said. At the seating depths I mentioned, one group should perform significantly better than the other groups. From there, you can further refine your seating depth if you wish. If 0.010" is too far into the lands, then start at 0.005".

 

[Bob 964]

On second thought, Sniper Uncle, I may agree with you. I overlooked the fact that he is loading 168 SMKs, which are not as sensitive to seating depth as the 208 Amax I shoot. For the SMKs, 0.010" jammed may be too much. Forgive the oversight on my part.

 

[oldfatguy]

SMKs don't like to be jammed in any of my rifles. But 0.010" jammed shows me the max charge under worse case conditions.

OFG

 

[Dfarmer786]

Thanks guys next time I get a chance to shoot ill play with depths.

 

[Sniper Uncle]

I never tried 0.010" jammed, but it seemed like a lot to me. I have only read about some guys doing 0.002"-0.003" jammed. While doing load development for my K-31, I discovered that it has virtually no throat. The bullets that were jammed wouldn't even stay 0.010" out. They seated deeper when the bolt was closed----not saying this always happens, but it did in my K-31.
I loaded the first set according to Hornady max COAL, and got massive pressure signs earlier than I figure I should. My uncle's K-1911 did not show any pressure signs with the same rounds. When I measured the chamber, the actual Max COAL for my K-31 was 0.020" shorter than that published by Hornady.
I have been skittish about doing any jammed loads ever since. Fortunately, my rifles seem to like some jump, so it doesn't matter.


Cheers,
Tim
The Right to Keep and Bear Arms Shall NOT be Infringed

 

[HobbyShooter]

On my Savage, just touching the lands gives me my best accuracy followed by .010" jammed then .010" jump and there is a noticeable difference between the three. .020" and further back really stink.

 

[HobbyShooter]

Oh, and I agree that 45.1 is your OCW.