Whats Your Crimp With Plated/jacketed Or Lead?

[steel1212]

I think my crimp is to tight at 473 with lead and jacketed is that about right or to tight.

[DougCarden]

For adjusting the crimp here is what I do. Resize a case and mike it with the calipers, run it through the powder die to bell the case, then run it through the Lee FCD and keep turning it down until I get the same measurement as the resized case. I then add the bullet and check the crimp.

For jacketed I keep adjusting the crimp and pulling the bullet until I see a faint line in the bullet, not a hard line, but a faint one that is visible all the way around. For lead I usually crimp a little more to get a good seal. I scientifically look at the round against a white wall with good light and watch the flare of the case go away until it is nice and smooth. All we are doing with the crimp is taking the flare of the powder die bell away. More accuracy is robbed from the ammo due to overcrimping that we will ever know...

I dont have any plated bullet data to give you. I could never get the accuracy I wanted with the bullets and dont load them.

Hope this helps!

DougC

[epj]

I think my crimp is to tight at 473 with lead and jacketed is that about right or to tight.

I shoot for about .471, pun intended.

[steel1212]

I think my crimp is to tight at 473 with lead and jacketed is that about right or to tight.

I shoot for about .471, pun intended.

Ok good so I'm not to tight, thanks.

[Joe D]

Thats funny Doug. I too use the very scientific method of looking at the flare. I use one of those battery powered magnifying glasses. My crimp runs 470"-471".

[RogerT]

I have problems with plated bullets, they creep out of the case when I fire my revo.

After three rounds the remining rounds on the clip are one millimeter or more longer, even if I have crimped them so hard that there is a visible line on the bullet, where it was seated from the beginning.

I suspect that my powder die funnel (Dillon #13426) is too large.

When I push a sized case of my match brass (AP) on the powder funnel until it stops against the bevel that bells the case, I can't remove the case with my fingers, it is stuck and I have to wiggle it hard from side to side to get it free.

Should it be so tight or should I take the funnel down a few hundreds of an millimeter?

Edited April 11, 2007 by RogerT

[blkbrd]

Chuck the powder die up in a drill press and polish down .001-.002"

An EGW U die will also help keep case tension up.

Crimp is the wrong term. Its a flare removal step.

[LPatterson]

The spec given in 3 different reloading manuals is .473 but does not list the brand of case measured. So take the brand of brass used most and measure the thickness of the case at 4 different points around the case mouth. Then measure the bullet to be used and add the 2 thinest measurements from the case mouth. Add .001 and this will give you a starting point, now press a loaded round nose first onto a solid object and the bullet should not move. If it does tighten the crimp .001 at a time until the bullet no longer moves. For my revo with Star brass & a Berry plated bullet this is .470, the 1911 with Federal brass & a Precision bullet is 471, factory Blazer brass is .469. YMMV

[RogerT]

The bullets still creeps out of the cases.......

I polished down the powder funnel until my most used brass is easy to push on, and the match brass (AP) is a bit tighter.

I measured the case mouth thickness and it's about 0.008 to 0.010. It all depends on how deep in the case I measure (using digital calipers), but I tried to measure only 1/10 in. down from the end.

Then I measured the bullet I'm developing a major load for, a plated lead bullet, 200 gn truncated cone shape. It is .450 to .452 at the base and .446 at the point where it is crimped when I seat the bullet.

So I figure that a crimp diameter of .446 plus .018 (2xcase wall thickness) should be more than enough, but not even a .464 crimp holds the bullet in place when I fire three rounds in the 625. OAL increases from 1.222 to 1.245 on all the three remaining bullets on the clip.

Now I have switched from the Dillon crimp die to a Lee FCD and adjusted the crimp to .462, the case mouth is almost flush with the bullet now, I will try them tomorrow.

Or should I just live with it? The ammo chronos OK, around 855 ft/s (too low for major, I know, but I stopped increasing the powder charge when I noticed how loose the bullet was in the case).

UPDATE: Not even crimping the sh-t out of the bullets with a Lee FCD @ .462 will hold them in the case, I'm now convinced that a taper crimp does not add to "bullet hold" at all.

POSSIBLE SOLUTION 1: Use roll crimp instead. What tool provides me with a roll crimp in .45?

POSSIBLE SOLUTION 2: Use the 2000 bullets left to practice only and shoot jacketed bullets in matches.

Edited April 13, 2007 by RogerT