- Thread starter levi8599
- Start date
Did you order a barrel from blackjack and then do the chambering? Any other information on your rig would be appreciated. I have a pre-fit ordered for a Bighorn Origin, 1:7 Rock Creek as well, as well as a bunch of 131s. I'm very curious to see any other results you get but so far looks promising. Do you have more testing you plan on doing?
Ordered a barrel from rock creek. Phoenix custom rifles ordered a JGS reamer From blackjacks specs and did the work. I’ll play with it some more but want to wait and see if it tightens up the more I shoot. I’ve tested from 41-42.2gr and 41.9 with oal 2.865 was where it landed. I played with seating depth from 2.85-2.875 as well. Anything over 41.9 for me started to open up.
Cool thanks for the report. What's your chronograph?
What dies are you using?
Redding 6.5cm FL bushing die with a .283 bushing. Right now I am using the regular 6.5cm seater but I may switch to the micrometer with vld stem. The seater hasn’t seemed to cause any issues right now so we’ll see.
I have Redding 6.5CM FL and neck bushing, a body die, and Micro seater so thats good to hear. I'm thinking about swapping to the 25. I'm just concerned that there's only one high BCbullet to choose from.
The upside of only one bullet is all the reamers are built with that bullet in mind. I'm actually excited about the simplicity of that. Load workup will not involve trying different bullets. Based on reviews and info it seems very unlikely you won't be able to find a load with that single choice.
I did a total of 7 loads and 3 of those loads I did at two different seating depths. I’ve never gotten that low of SD and ES. We’ll see if it tightens up with more rounds but as of right now I might not play with it much more. I’ve gotten to the point that I hate load development I just want to shoot lol
from everything I’ve seen with it, it’s very forgiving with seating depth and almost everyone finds the same node in 2900-2950
from everything I’ve seen with it, it’s very forgiving with seating depth and almost everyone finds the same node in 2900-2950
Here’s where I’m currently at with mine. I’m not happy with the 205Ms for the SRP Creedmoor case but I haven’t ran into any CCI #450s in stock when I’ve ordered other hazmat stuff. Shots 33-50 are in strings 1-2 on even numbers from 41-42.6, then I ran 51-70 from 42.4-42.8 at .1 increments 4 shots each. Shots 1-32 are not included because it sped up 50-60fps for same load/needed .6ish less grains to make the same velocity.
New 6mm Lapua Brass expanded to 25, no other work. A tad too long for my chamber, unfortunately, so I’ll probably bump the shoulder back and do one more test before picking something and running with it. No real comments on accuracy yet as I’ve been shooting off a folding table and messing around with swapping between a 6mm and 6.5mm brake. Probably should just put on the 6.5 and be done with it but that would make too much sense.
New 6mm Lapua Brass expanded to 25, no other work. A tad too long for my chamber, unfortunately, so I’ll probably bump the shoulder back and do one more test before picking something and running with it. No real comments on accuracy yet as I’ve been shooting off a folding table and messing around with swapping between a 6mm and 6.5mm brake. Probably should just put on the 6.5 and be done with it but that would make too much sense.
How did you expand the 6 creed brass?
what jump did u use?
Ran essentially the same charges again (rounds #76-100) after cleaning. Did it in the afternoon at 100* vs morning at 75-80*. At around 100fps gain/1gr less for same velocity relative to the initial loads I ran up to 43.9gr.
How was the group with 42.7?
Would’ve needed a fancier target stand that actually held the target still with the wind today to give you a proper answer on that. Previously, these all shot around .5-7“. I’ll be back at it later this week to confirm a few groups, BC, and then zero out without the Magnetospeed on there.
That 42.7 definitely looks promising. I also would love to hear how your group sizes turn out with that load. I'm amazed how much faster this is than the first time you did it.
Did you neck turn or just expand and shoot?
I’m expanding and shooting. Current process is:
1st firing: 6 CM Lapua brass -> Expand, Load, Shoot. Here, the expanded brass is a thou or so too long, so there’s a slight resistance on bolt close. I could see if virgin peterson comes out different. I haven’t bothered integrating a shoulder bump into the process as everything has cambered just fine.
2nd firing: Fired Brass -> FL Redding 6.5 Bushing Die (.283) and shoulder bumped back to no resistance ||Currently here until I run 300 more virgin pieces through|| -> Set neck tension with expander, Load, Shoot.
3rd+ firing: Same as above, more or less, unless only neck sizing or something.
Last edited:
Did you use a long throated reamer? At 2.867 I'd be about 10 thousandths into the lands. I'm at 2.842 (rough average) and 15 thousandths off. What's your CBTO? Mine is 2.175, so 2.190 is at the lands. Just curious, I'm starting to wonder if I'm measuring something wrong, haha, anyways thanks.
Last edited:
Appreciate the sanity check!
My reference CBTO touching the lands* is 2.186
You simply have a lot with shorter bullet lenght.
BTW there is nothing wrong with your CBTO measurments.
