Next Step In 300WM OCW

[.50 Cal Cow]

Conducted two OCW tests this weekend. Looking for some advice or recommendation on next step. Rifle is Rem 700 Sendero SFII chambered in 300 Win Mag with 10" twist.


Test 1
Bullet: 210SMK
Powder: H1000
Brass: Hornady
Primer: CCI 250
OAL: 2.785" to Ogive (equates to 0.010 jump)

Notes: Charge at 75.5 is only 2 shots as had a primer that didn't go bang. No pressure signs through test. My thoughts are that 76.2 and 76.4 are about same POI and that 76.4 is OCW but try 76.6 to see the span.

Test 2
Bullet: Hornady 180gr Interbond
Powder: IMR4831
Brass: Federal
Primer: CCI 250
OAL: 2.790" to Ogive (equates to 0.010 jump)

Notes: Thoughts are that 71.7 to 72.3 are close to same POI (72.0 and 72.3 for sure) and that 72.0 may be it as much as I want it to look like 71.7. Haven't figured out the scatter on this one although 72.5 looks like one. Hodgon listed 74gr max for 4831 and 180gr bullet so guess could work way up to confirm 72.5 as a scatter.

If next step is seating depth what increments work best? I have a chrono and plan to bring it out next test just want to make the most of the next set of loads. Thanks.

 

[Brentc]

Re: Next Step In 300WM OCW

I'd say 76.5 with the H1000 load will pull the group together. Don't mess with the seating depth until you nail down the powder charge. I'd agree with your 4831 conclusion. See what happens above 72.5.

 

[.50 Cal Cow]

Re: Next Step In 300WM OCW

Thanks man.

As for the H1000 I actually loaded a few more around the 76.4 the 76.6 range just to see if they remain around same POI.

As for the 4831 I loaded a set at 72.0 varying the seating depth. My plan was to chrono and see what I am putting it out to. If I get a solid grouping and velocity spread my thought was to just call it since this would be more of a shorter range hunting load. If there's room for improvement I'll investigate the range above 72.5.