What am I doing wrong?

[BrokenWheel]

Trying to reload for my sw 500 and I'm getting frustrated by the variability between cartridges oal.

equipment: Hornady LnL, Hornady custom dies.

reloading manual state that the OAL of the cartridge for the 500 should be 2.020. When I seat the bullet I get consistent lengths. However, the moment I crimp, the crimp seems to push the bullet into the cartridge - so my oal gets reduced to 2.010. Lighten up on the crimp and the length gets longer, try to put a decent crimp on it the oal shrinks to 1.995!

I've tried to reduce the seating depth of the bullet but still the crimp pushes the to 2.010. I've tried to not crimp on the bullet seater die and just crimp using the crimp die (4th die supplied in the Hornady kit) with the same results.

I even measured the case lengths and they are all about the same.

Suggestions?

 

[Walkalong]

Don't sweat it.

Seat the bullet so the case mouths rolls into the deep spot of the cannelure nicely at whatever amount of crimp you want to use. Whatever O.A.L. that gets you is OK.

Case being trimmed evenly (+ or - .001 is my goal) will help get better, more consistent crimps, as well as O.A.L.s since crimping is changing the O.A.L..

 

[Sam1911]

I've had that exact situation with revolver cartridges shooting cast bullets. Because of the shape of the crimp grove on most lead bullets, when you crimp the case mouth, it pulls the bullet down until the underside of the upper edge of the crimp groove bottoms against the case mouth. I just crimp firmly and let the groove dictate the OAL.

I've never seen a jacketed bullet do that, but their cannalures are totally different and don't have any taper.

-Sam

 

[rg1]

Are you backing out the bullet seating stem after seating the bullet? If not the stem will push the bullet in deeper when adjusting the seater die down to crimp. Back the bullet seater out all the way. May not apply here but just a thought.

 

[Walkalong]

let the groove dictate the OAL.

Yep.

 

[BrokenWheel]

Sam - thats exactly whats happening to me with cast lead bullets! What did you do?

rg1- I did that!

"let the groove dictate OAL" Thats fine, and 2.020 puts me in the middle of cannenlure, but when I crimp it pushes the bullet deeper into the cartridge..

 

[Sam1911]

No, I think you're misunderstanding all of us.

"Let the groove dictate the OAL" means let that tapered groove draw the bullet down until it seats against the case mouth -- as the bullet is designed to do. Let it go where it needs to go and don't fuss with it.

Leave the worries about the exact OAL measurement the book gave you to when you're loading jacketed bullets with their different, flat-bottomed, cannalures.

-Sam

[EDIT: If you're trying for the absolute pinnacle of accuracy, you can trim the cases all to the same length. That way, when the bullet seats ITSELF against the case mouth, your OALs will be consistant. But I don't worry about that at all in my loading.]

 

[Walkalong]

means let that tapered groove draw the bullet down until it seats against the case mouth -- as the bullet is designed to do. Let it go where it needs to go and don't fuss with it.

My bold.....Yup. Worrying too much. You are good to go.

 

[BrokenWheel]

Thanks - so the moral of the story is that a good crimp is more important than OAL.

 

[Walkalong]

The moral of the story is that the cannelure determines O.A.L. on revolver bullets.

The bullet makers understand what loads will be used with their bullets. They understand the limits of cylinder lengths as well. They don't just roll the dice when choosing where to put the cannelure.

I log the O.A.L., just like I do on everything, but I don't shoot for a certain O.A.L., I let the cannelure determine it.