HELP me with my stroke! 6.5 Creedmoor super short?

[packer58]

I would measure your cases and make sure you didn’t happen to miss them when you trimmed. Back die out another half turn.

Dang-it, your a faster typer than me. Iv'e always just placed a nickle on my shell holder for seating die setup.

 

[packer58]

I agree. But you shouldn’t get collapsed shoulders with your neck .001 smaller than the bullet.

We are on the same page here, but something is happening above the shoulder applying enough pressure to collapse the case. That's why i asked the OP to measure the mouth of a sized case after mandrel, neck tension may be more than we think it is ??

 

[Pickettpuncher]

We are on the same page here, but something is happening above the shoulder applying enough pressure to collapse the case. That's why i asked the OP to measure the mouth of a sized case after mandrel, neck tension may be more than we think it is ??

I’ve collapsed a few cases and it was usually a set up issue. Can’t say I’ve ever heard of using a nickel but if it works…

 

[Wrench]

Spin that seater die body up two turns and then seat a bullet.

 

[packer58]

I’ve collapsed a few cases and it was usually a set up issue. Can’t say I’ve ever heard of using a nickel but if it works…

It's funny the nickle thing even came up, but i think in some of the old RCBS setup instructions it makes reference to a nickle between the shell holder and bottom of seating die at full stroke.

 

[NevadaMike]

I agree. But you shouldn’t get collapsed shoulders with your neck .001 smaller than the bullet.

So if the projectile is .264 and my mandrel is .262 that would be .002 plus any spring back. Would that be enough to cause the problem?

 

[packer58]

So if the projectile is .264 and my mandrel is .262 that would be .002 plus any spring back. Would that be enough to cause the problem?

That .002 diff is divided by 2 plus spring back.

Put another way, .002 diff would be .001 all the way around the circumference of the bullet.

 

[Pickettpuncher]

So if the projectile is .264 and my mandrel is .262 that would be .002 plus any spring back. Would that be enough to cause the problem?

In my opinion, no. Not if you’re using boat tail bullets

 

[Lawnboi]

So if the projectile is .264 and my mandrel is .262 that would be .002 plus any spring back. Would that be enough to cause the problem?

The problem is spring back. Depending how much you’re sizing the case, how you are lubing and if it’s annealed, spring back can change a lot. A creedmoor case squeezed to .285 in a standard die and then run through a mandrel is not likely leaving you with .002 or .003 neck tension.

Took me way too long to learn this. The more you work the brass, the more spring back happens, creating inconsistency and work hardened necks. I tried doing the same as you with a 223 Redding fl die, it squeezed my necks to .010 neck tension before the expander. Even with a .001 under expander mandrel I was still seeing what I thought and felt was excessive neck tension. To the point that seating a bullet on my arbor press was a pain in the ass. So much work placed on the brass left very inconsistent seating force as well even on an annealed case.

I personally wouldn’t waste your bullets, primers or powder on Hornady brass.

 

[NevadaMike]

The problem is spring back. Depending how much you’re sizing the case, how you are lubing and if it’s annealed, spring back can change a lot. A creedmoor case squeezed to .285 in a standard die and then run through a mandrel is not likely leaving you with .002 or .003 neck tension.

Took me way too long to learn this. The more you work the brass, the more spring back happens, creating inconsistency and work hardened necks. I tried doing the same as you with a 223 Redding fl die, it squeezed my necks to .010 neck tension before the expander. Even with a .001 under expander mandrel I was still seeing what I thought and felt was excessive neck tension. To the point that seating a bullet on my arbor press was a pain in the ass. So much work placed on the brass left very inconsistent seating force as well even on an annealed case.

I personally wouldn’t waste your bullets, primers or powder on Hornady brass.

I think you are right on both counts. This was the last of never fired Hornady brass and I think combined with the neck tension problem lead to the creative cartridges. Fortunately I have 500 Peterson cases waiting to go in line next. I need to get more consultation on the neck tension problem before I mess with them. I intend to deprime, clean and anneal some of the once fired Hornady stuff and use the decap pin and ball expander that came with the die just to see how it checks out. After everyones help here I am fairly confident that will take care of the problem.

 

[Lawnboi]

I think you are right on both counts. This was the last of never fired Hornady brass and I think combined with the neck tension problem lead to the creative cartridges. Fortunately I have 500 Peterson cases waiting to go in line next. I need to get more consultation on the neck tension problem before I mess with them. I intend to deprime, clean and anneal some of the once fired Hornady stuff and use the decap pin and ball expander that came with the die just to see how it checks out. After everyones help here I am fairly confident that will take care of the problem.

The Peterson will be easy in that it won’t need to be sized before loading. I’d use a turning mandrel with some imperial wax on the lip, dry tumble it take that factory anneal grit off along with the lube, chamfer, debur, and load.

Take measurements of the new brass. I buy small notebooks, the $1 kind and assign it to that barrel for all load work. That way you know what your factory spec is, likely you won’t want to bump much at all on the first firing as it usually takes a couple shots to reach your chamber dimensions.

Another thing I do, is keep 10 or so pieces of brass as testers, and load them 2-3 firings in front of wherever your current batch is. This will show you what’s going to happen as you load without goofing up a batch of 100+ pieces.

 

[AkRyan]

LUBE! If only 10 out of 100 are bad it's a you thing not a mechanical. How many cases do you lube at a time? Are you using a brush to lube the neck? If your doing 10 at a time and 10 out of 100 are bad my guess is your running low on lube by the time you do #10

 

[Harvey_NW]

I've never tested it myself, but I've seen claims that dwell time on a mandrel can reduce the amount of springback as well. Regardless, most of my die sets are factory FL and I've never had an issue with so much springback it would crush shoulders on seating, especially using graphite lube. Only when my seating die was improperly setup, as said.

 

[BjornF16]

It looks to me that your seating die has a crimp feature that is engaging the neck too early (i.e. die set too deep).

Don’t ask me how I know

 

[NevadaMike]

I spoke to 21st century and Unknown munitions. I think it's a combination of not enough lube and the brass not being the toughest out there. I had imperial case lube but not the ceramic beads. I think just dipping the rim in a small pile in the cap was not enough. The Imperial case lube with the beads will get here tomorrow.

As far a crimping I am not sure. I place a piece of brass in the holder and raise the ram with no projectile. I then thread the die until it touches the brass and them I back it off some. I think this should keep it out of the crimp correct?

 

[Laelkhunter]

Did you chamfer the inside of the case mouth? I found most of my bullet seating problems occur when I don't chamfer the inside of the case mouth enough.

 

[NevadaMike]

Did you chamfer the inside of the case mouth? I found most of my bullet seating problems occur when I don't chamfer the inside of the case mouth enough.

I did but not enough. I think it was a combination of problems. Super clean and sticky brass, no neck lube for the mandrel and not enough graphite seating the bullets. I have completely revamped my brass prep and focus on neck tension. All my brass is now getting the Henderson treatment, honed Forster dies and graphite lube.