first OCW at 300 yrds, need suggestions

[cvonessn]

The problem with my rifle (Sako TRG22) is that it'll shoot everything...I've tried all variations and it doesn't <span style="text-decoration: underline">not</span> like any of them so narrowing down the best combo is aggravating! Every combination so far is decent but as I continue the search for the almighty round I'm now trying the 155 lapua scenar SJ's over Vihtavouhri n540...any suggestion on the proper OCW? (Shot at 300 yards and it was around 40 degrees)

 

[Jedi]

Re: first OCW at 300 yrds, need suggestions

that is more akin to ladder test than OCW

Did you hit max for rig via observed ejector wipe/bolt lift
if not keep going

47.8 vargay is common load with 155 skinnie
if yoour not going to find max for rifle then based on info
46.3

I always find max n work backwards, no need giving away velocity for lack of testing

 

[B3dlam]

Re: first OCW at 300 yrds, need suggestions

If you can shoot past 300 say out to 500 I would recomend doing a ladder test at 500 using loads from 44.5-45.5 in .1 grain increments and perhaps another from 46-47 in .1 grain increments. then look for where the sweet spot in that load is. Once you have that sweet spot load up that charge and shoot it for groups at extended distance.

 

[cvonessn]

Re: first OCW at 300 yrds, need suggestions

my max I can get to is 300yrds so I'll work up another two strings at lesser powder increments and see what happens...I did another string with CFE223 on 178 Hornady's and it was basically worthless...you have to do it at 300yrds

 

[shoot4fun]

Re: first OCW at 300 yrds, need suggestions

I think you should go back and read Newberry's writing on OCW again.
I work up all OCW at 100 yards, first for charge weight and then seating depth. I have not found any load developed in this manner to fall apart at longer distances, even out to 1000 yards.
The picture I see is more a ladder test than OCW.

 

[Niles Coyote]

Re: first OCW at 300 yrds, need suggestions

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: shoot4fun</div><div class="ubbcode-body">The picture I see is more a ladder test than OCW.</div></div>

+1 but from what you posted it looks like 44.5-45.5 is a nice place to start...

 

[cvonessn]

Re: first OCW at 300 yrds, need suggestions

Yes, you guys are right, its more of a ladder test

 

[Bob 964]

Re: first OCW at 300 yrds, need suggestions

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Niles Coyote</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: shoot4fun</div><div class="ubbcode-body">The picture I see is more a ladder test than OCW.</div></div>

+1 but from what you posted it looks like 44.5-45.5 is a nice place to start... </div></div>

Regardless what you call this (and it is a ladder test), I'm with Niles on this. Your 44.5 - 45.5 gr. node does look like it provides the least vertical dispersion. So... I think you have several options, including but not limited to:

1. You can go with the mid-point (45.0 gr.) of this node and test rounds with different seating depths.

2. You can repeat your ladder test procedure using smaller increments (like 0.2 gr.) and limiting your charge weights to those just below and just above your node (e.g., 44.3, 44.5, 44.7, 44.9. 45.1, 45.3, 45.5, and 45.7 gr.) in an attempt to further refine your node.

3. You can do an OCW test at 100 yards following Dan Newberry's instructions to see if you can confirm your ladder test results.

I've used both the ladder test and OCW to try to find the best charge weights and seating depths. I have more confidence in the OCW technique because it spreads any error factor across all groups equally (since you have 3 shots at each charge weight).