Updated info in post#99 Preferred Barrel 6mm Creedmoor help

[Eric H]

Yes, i have went from .004 neck interference fit to .0015 using a mandrel and graphite (powder and liquid ) in the neck

I think you'll find something you like.

 

[Hugnot]

H4350 should be among the best powders.
CCI 450's (SRP) should be among the best primers.

Will bullets consistently slip fit into fired brass, (.0015 is sort of skinny)?
Is neck tension consistent, possibility of brass spring back with work hardened necks with reloads?
Accuracy evaluated with fired brass if reloads used or virgin brass?
Ogives consistent with near or touching bullets?

I did this a few years ago, 5 bullets - real good & if all things work can duplicate - clean barrel, check out slip fit, anneal every 5, trim .......



My rifle has a 8 twist McGowen, Ruger M77, MK II, 105 Barnes Match Burner bullets seated 10 thou from touch and seating depth redone to same every batch reloaded. Laminated Richards stock bedded with JB Weld steel epoxy.
Velocities just under 3,000.
Note necks turned to .268. Brass is cheap 1X fired Federal SRP 6.5 CM necked down to 6mm & turned to .268.
Brass F/L sized without expander, Hornady F/L die, then neck sized with Lee Collet Die.
Accurate 4350 powder - real cheap back in 2022, like under $30/ lb at LGS's but not now. I have switched to SW 4350 and load .2 grains more.

Evaluating the Sg stuff:




Everything looks real nice for either a 7.5 or 8 twist. The OP sez 7.5 T

I like to avoid Sg values greater than 2.0 and bullet wizards using the Miller analysis agree.

I have a unopened box of 6mm 103 ELDX's that I am saving in the event for shooting deers and other. The length measurement came from JBM and occasionally needs minor corrections.

 

[Dirtrax]

I'm gonna just come right out and say it…that dog don't hunt. You're wasting your time now. I know it sucks but it happens.
If you prove me wrong I can only be happy for you.

 

[Justice1327]

I think you'll find something you like.

200rds in…not looking good
A tad bit more with h4350 and then I'm gonna go to 90 gr bullets with varget

 

[Justice1327]

I'm gonna just come right out and say it…that dog don't hunt. You're wasting your time now. I know it sucks but it happens.
If you prove me wrong I can only be happy for you.

Thanks

 

[Justice1327]

H4350 should be among the best powders.
CCI 450's (SRP) should be among the best primers.

Will bullets consistently slip fit into fired brass, (.0015 is sort of skinny)?
Is neck tension consistent, possibility of brass spring back with work hardened necks with reloads?
Accuracy evaluated with fired brass if reloads used or virgin brass?
Ogives consistent with near or touching bullets?

The .0015 was the .200datum line, but yes they do slide in easily
I use an AMP each time and they all feel the same with the mandrel and seating of the bullet
No real noticeable diff between virgin and fired
Have worked bullets close to lands and up to a .100thou off

 

[Eric H]

The 80Gr ELD VT looks promising in a 7.5 twist.

 

[Justice1327]

The 80Gr ELD VT looks promising in a 7.5 twist.

Yep, but this is for deer hunting

 

[Eric H]

Don't know if you've had experience with Hammer Bullets but they have on their website the recommended twists for each bullet. You can PM RockyMtnMT and he'll give you suggestions of bullet and powder for the 7.5 twist.

 

[Justice1327]

Don't know if you've had experience with Hammer Bullets but they have on their website the recommended twists for each bullet. You can PM RockyMtnMT and he'll give you suggestions of bullet and powder for the 7.5 twist.

Thanks but this guy doesn't want expensive bullets, just deer and steel , his first custom gun…i feel bad for him.

 

[Eric H]

Don't know what to tell you. That dog won't hunt. The powders that normally work great are H4350, RL16 and H4831SC. And this is supposed to be a new barrel?

 

[Hugnot]

Stuff happens - a possibility could/might be some barrel situation. Did the barrel maker suggest a break in procedure for new barrels?
Clean it up squeaky clean, mirror like.
Try the relatively cheap Barnes Match Burners - not intended for shooting deers but seeing nice groups will infuse your perspective with confidence & happiness. Try keeping pressures under 61K psi. The Sierra 100 GK is another possibility with a 7.5 twist.
That 7.5 twist will also handle 112's & 115's.

 

[Justice1327]

Don't know what to tell you. That dog won't hunt. The powders that normally work great are H4350, RL16 and H4831SC. And this is supposed to be a new barrel?

Yes new PBB barrel

 

[lyle2231]

Good morning, May I suggest call Hornady and ask them what their accuracy load development showed. That should give you another idea. FWIW