I think I'm hooked...

[GreenBlood10]

Last year I had a custom .300WM built along with a GAP-10G2 from G.A. Precision. After going through a few boxes of ABM ammo (@ $58/box), I decided to get into reloading. In December I started acquiring everything I would need to start reloading for the GAP-10 which is chambered in 6.5 Creedmoor. I purchased both the Lyman and Berger reloading manual and read it as much as I could along with most of the sticky threads here on the Hide. Today I shot my very first reloads while conducting my very first optimal charge weight (OCW) test. I was using new Hornady brass, Federal GM210M primers, H4350, and Berger 130gr AR Hybrid OTM Tactical. My equipment list and process is as follows:

Using a Forster Co-Ax single stage press I ran the Hornady brass through a Redding Type-S Full length sizing die with .287" titanium nitride bushing and carbide button
I then trimmed the brass to the shortest Hornady case in the box (1.912") using a L.E. Wilson micrometer case trimmer.
I then uniformed the primer pockets, deburred the flash holes, and chamfered/deburred the case necks.
I then cleaned out the cases with an air compressor and primed them using the priming station on the Forster press.
Using the Berger manual, I used a Redding Match Grade 3BR powder measure to drop my charges.
I weighed each charge using a Frankford Arsenal DS-750 digital scale.
Using a Redding competition seating die, I seated each bullet .010" off the lands. (Determined using a Hornady OAL gauge)

The OCW test was shot at 100 yards and conducted "round robin" style. The temperature was 70* with a headwind less than 4mph. I do not have a chrono yet so I can not give you velocities.
What do you guys think? The targets in the upper left of each cardboard were used as sighters as I didn't expect them to do very well being below book minimum. I had a lot of fun loading up these rounds and I cant wait to get back to the bench to reload them! Thanks for all the guidance you guys have given me so far on this journey.

 

[spife7980]

40.2 and 41.4 as the charges either side impact at the same relative location. I'd test 40-40.4 in .1 increments.

41.4 will have the advantage of velocity but with the groupings either side of 40.2 I would think that would be more consistent. I bet the chrono numbers would back that up as well. The brass life will be better as well with less extreme pressures provided they are fast enough.

I agree though. Reloading is every bit as addictive to me as shooting is if not more so.

 

[GreenBlood10]

Thanks spife7980 ! Will run another test from 40-40.4. Might run another one around 41.1 just to see.

 

[nexusfire]

Did you see pressure over 42.3?

Sent from my SM-G935V using Tapatalk

 

[GreenBlood10]

Didn't go any higher than 42.3 during this test nexusfire . I am going to run another test from 42.5 up to 43.1.

 

[GreenBlood10]

One last question. The Sentry adjustable gas block on the rifle was previously tuned for the Prime 130gr ammo. I have read that some people settle on a load, tune their gas block for that load and then their groups open up. I'm trying to avoid that. Should I leave it tuned as is (tuned for Prime) unless I start to see issues or tune it for my final load?