Jason’s 338-375 Ruger Build

[Jason]

Loads development as follows, 5 shot strings at 100yds.

H4350 with 250 Accubonds
76.0gr avg speed 2888fps, 1” group
76.5gr avg speed 2912fps, best group at .75”
77.0gr avg speed 2938fps, 1” group
No pressure signs with above loads.

H4350 with 250gr Berger Elite Hunters
76.0gr avg speed 2863 fps, 3” group
76.5gr avg speed 2900fps, 2.25” group
77.0gr avg speed 2915fps, 3.375” group
Loads speeds were all over the place. Groups were bad, will run strings again with Berger’s seated to the lands. Above Berger loads seated short to fit in mag. No pressure signs.

[jasnt]

With the 250gr Berger I had best groups at 20 k off or 10k jammed   Jme

[Jason]

With the 250gr Berger I had best groups at 20 k off or 10k jammed   Jme

Thanks for the info 👍

I loaded them 20k off, I will load the next Berger rounds 2k off, touching and jammed and see what those groups look like.
I still have plenty of room for the Accubonds to go longer. I will run another batch of virgin brass at a half to full grain higher and see what pressure looks like.

[Jason]

Jasnt, FYI Atlas Development Group is taking preorders on 300 prc brass.

[jasnt]

Jasnt, FYI Atlas Development Group is taking preorders on 300 prc brass.

Thank you but I got enough brass to finish this barrel off. 

[Jason]

With last weekend being so nice I was able to get some more load testing in. I was really hoping to get the 250gr Berger’s EH dialed in and that was my focus. First group was better than the last test session where the best group was about 4 inches and seated 10k off the lands. This time I loaded these touching the lands. First group at 76.5gr H4350. The group is getting better but not near what I was hoping for, avg speed was 2988.
Second load 77.0gr also seated to the lands, was grouping great and then things started getting interesting. Out of the five rounds I loaded I could not get the last two primers to fire. I tried several times each. The group of three was the tightest group that I’ve got the Elite Hunters to shoot and I was able to control my flinch with the duds. Avg speed was 3001.
I tried a string of Accubonds I had loaded and I had another primer that took three strikes to fire. I called it a day after that. I’ve never had this issue before so I’m hoping I over lubed the firing pin assembly. I’ve got it all cleaned up now.

[Jason]

Good time to show off my custom rear bag. Worked in a pinch since mine was at home.

[Magnum_Willys]

Change primers ? Those look nasty.

[Jason]

Change primers ? Those look nasty.

Nope, I didn’t change anything. I tried 3 to 4 times on each to get them to ignite. I didn’t really want to mess with pulling them. Makes me pucker

[jasnt]

Those Winchester primers? I had some primer troubles last fall.  Frustrating
I’d try some fed 215m’s
Bad batch of primers could be affecting accuracy too

[Jason]

Those Winchester primers? I had some primer troubles last fall.  Frustrating
I’d try some fed 215m’s
Bad batch of primers could be affecting accuracy too

Yep, Winchester's. I've always had great luck with them and I have a pile of them. I'll see if I can find some 215's.

[Magnum_Willys]

Good investment just to pick up a brick of 215M's.   Midway expects em in at months end.  $44.

[jasnt]

I just remember a while back a few bad batches of Winchester primers being talked about.  Maybe give them a call with your lot number.   

[Jason]

I lucked out today. I actually found some primers locally and they were only $32 out the door.

[Magnum_Willys]

Dang!  Back when it looked like Hillary was gonna win I paid  like $180 for that brick on gunbroker and going price was $250 !