300RUM First Load Test Results...

My RUM doesn't seem to mind a good jump either. No experience with the ELDs but Berger and Hammer do well with a little run at the lands.
 
Thanks. I loaded up some some 87.5gr last night with some others. Going to do one more good charge test to confirm what I'm thinking and then I'll tinker with seating. I keep reading these ELD-X's like to be .01" off the lands but I don't like being that close for a hunting round. I'll start at .02" and go from there, maybe .015" if they are lights out. I've never done seating testing in increments smaller than .005" and usually use .01" or even .02" increments to start out.

I never did either until I watched a youtube video.

Your 88gr group is really close so just a slight tweak to seating may make it better.

If groups are larger, I will go more aggressive, sometimes .020" and see what it does. If it gets tighter, I start reducing the amount.
 
I feel the same about hunting rounds needing more clearance. Last thing you need in the field is a hard to chamber round or a bullet getting pulled out and dumping powder all up everywhere. Plus 💩 happens in the field. Not that we're cramming muddy ammo into our chambers but even differences in temperature affecting metal expansion, to say nothing of the possibility of getting moistire
Or even slight dust on your rifle or ammo, and a cartridge set up to have a little jump is a heck of a lot more forgiving of real world possibility regarding pressure spikes than one that's starting out touching.
I've had nightmares of badly sticking a bullet in a barrel on one of my lightweight mountain rifles 10 miles back in the backcountry. I DON'T want to be that guy. Like you said... chit happens in the field. This is not a pack mountain rifle, but I still don't want to be that guy. No closer than .02" to the lands for me in my hunting rigs.
 
I run the 220s at mag length which equals a .120 jump. 88 grains retumbo. Christensen ELR. 3000fps. Tried to run them longer they did not like it in mine. For a hunting rifle your already "there". Nice work.
That's a good jump... I have an extended box in this one so can go a little longer. I'll add a little longer jump to my list of ideas to tinker with. Thanks.
 
My RUM doesn't seem to mind a good jump either. No experience with the ELDs but Berger and Hammer do well with a little run at the lands.
Bergers like a little more jump in most of my other sticks I shoot them in. Lots of guys shoot these ELD's right up touching the lands. I'll play with them a little more off and see how they do.
 
I never did either until I watched a youtube video.

Your 88gr group is really close so just a slight tweak to seating may make it better.

If groups are larger, I will go more aggressive, sometimes .020" and see what it does. If it gets tighter, I start reducing the amount.
Right! I probably shouldn't tinker at all and just start on my DOPE charting... the "what if" tinkering part of me gets the best of me more times than not. I keep telling myself I'm not going to get too crazy with this one... dead is dead on a good placed shot!
 
Right! I probably shouldn't tinker at all and just start on my DOPE charting... the "what if" tinkering part of me gets the best of me more times than not. I keep telling myself I'm not going to get too crazy with this one... dead is dead on a good placed shot!
All part of the fun. If we only shot them while hunting a guy's only get to pull the trigger a few times a year. That'd b pretty boring.
 
Did a couple more rounds of charge testing and have my best results at 86.0gr or 87.5gr of H1000. The 87.5gr is just under 3000 fps. Next I'm going to mess with seating a little and then hopefully call it good. 100yds results string of 7 shots.
 

Attachments

  • 87.jpg
    87.jpg
    48.5 KB · Views: 28
Top