what size bushing you using for the Lapua 6.5 creedmoor brass?
- Thread starter ArmyJerry
- Start date
AJ, if you have access to a ball mic I use this formula.
Neck thickness times 2 plus bullet diameter minus .002
For example: .013 x 2 = .026 + .264 = .290 - .002 = .288
As lapua may be .014 or so .290 should be close.
R
Neck thickness times 2 plus bullet diameter minus .002
For example: .013 x 2 = .026 + .264 = .290 - .002 = .288
As lapua may be .014 or so .290 should be close.
R
Bring this back from the dead.
I am running a .289 bushing and I'm having a couple Lapua cases where the Bullet will slide in and out of the case freely.
I out in a .289 bushing and resized those cases and they are tight again but feels too tight.
Out if 50 once fired cases I'm getting approximately 2 that the bullets will slide in and I can pull them out by hand pretty easy.
The brass is all once fired with 42.2 grains of H4350 and a 140 ELD. I am also using Redding dies and bushings.
The bullets are also seating with little force but it's hard to tell how hard on my CO-AX.
Any ideas on those cases ashes that are too loose? Just run them through the .288 bushing and move on or am I running to little neck tension already with the .289?
I am running a .289 bushing and I'm having a couple Lapua cases where the Bullet will slide in and out of the case freely.
I out in a .289 bushing and resized those cases and they are tight again but feels too tight.
Out if 50 once fired cases I'm getting approximately 2 that the bullets will slide in and I can pull them out by hand pretty easy.
The brass is all once fired with 42.2 grains of H4350 and a 140 ELD. I am also using Redding dies and bushings.
The bullets are also seating with little force but it's hard to tell how hard on my CO-AX.
Any ideas on those cases ashes that are too loose? Just run them through the .288 bushing and move on or am I running to little neck tension already with the .289?
The light ones likely have thinner necks. If thats the case, consider culling those cases. There's no fix except for neck turning the fat(normal) sized cases to match them. Something else to note is that those bushings are not perfect. Despite their markings, they may be smaller or larger. If you're not using an expander ball, you can take some micrometer measurements of the sized neck to give you an idea of what it's actual size is. Dont forget that the necks are springing back some after sizing. I have some redding bushings that are .001-.0015 undersized. When you move between your .288 and .289, you could be seeing some of that. They are generally tapered somewhat as well. If you flip that .289 over (run it numbers down), you'll probably get a little more sizing. The exact amount varies from bushing to bushing. Fwiw, I run wilson bushings when i can. I own dozens of bushings, and the wilsons are more consistent, have better internal finish, and better tapers.
Do you anneal? Is it possible you overcooked some of the necks?
Do you anneal? Is it possible you overcooked some of the necks?
