For those that seat/crimp separately, do you then re-seat?

[Typetwelve]

With pretty much any straight wall round that I load (38 spcl, 44 magnum, 460 S&W, projectile doesn't matter, they all do it the same way), I've noted that when I seat to the proper depth (and verify that with a mic), after crimping, it will "squeeze" (for lack of better terms) the projectile back out a bit. Typically a min of +.005", upwards of +.010 OAL". If I then place it back in the seating die, it will seat it back properly (without effecting the crimp). I run Dillon and Hornady dies for these rounds, doing seating on one die, crimping on another. This happens on both my Dillon 550 and RCBS single stage.

has anyone else noted this?

 

[AJC1]

With pretty much any straight wall round that I load (38 spcl, 44 magnum, 460 S&W, projectile doesn't matter, they all do it the same way), I've noted that when I seat to the proper depth (and verify that with a mic), after crimping, it will "squeeze" (for lack of better terms) the projectile back out a bit. Typically a min of +.005", upwards of +.010 OAL". If I then place it back in the seating die, it will seat it back properly (without effecting the crimp). I run Dillon and Hornady dies for these rounds, doing seating on one die, crimping on another. This happens on both my Dillon 550 and RCBS single stage.

has anyone else noted this?

The bullet can move based on the shape of the crimp groove. I do not try and move a bullet after crimp because the crimp is supposed to prevent it.

 

[Blue68f100]

I don't worry about the OAL, I let the cannelure set the OAL. When I setup my crimp I try to have the end of the case at the top of the groove. Now if you have not trimmed your brass so it's all the same length you should setup on a long one and let the rest fall where they may.

To answer your question No.

 

[Barmcd]

I don't. I use the cannelure on those bullets that have them, but I use a lot that don't have one. Its such a small amount I don't think it makes a difference.

 

[film495]

I don't go back, but I might adjust my seating depth to compensate if it mattered to me.

 

[GeoDudeFlorida]

I've noted that when I seat to the proper depth … after crimping … the projectile back out a bit. Typically a min of +.005", upwards of +.010 OAL".

Above edited for brevity.

I would suggest that perhaps if the bullet is moving under the crimp die it is not seated to the proper position with respect to the case mouth. If the desire is that the COAL, crimp groove and seating depth all align according to the book specifications, then you will need to trim your cases and adjust your seating so that the top of the crimp groove lands on the case mouth precisely at the point where the overall finished length matches your specifications. The crimp die will then roll the case mouth into the groove so it won’t move.

 

[Palladan44]

Yeah, cannelures can be "U" shaped, I've seen this happen in 44 Mag and 357 mag. But it's been very minute. I've noticed more variance in the projectile total lengths from bullet to bullet than the amount that the crimp affects the OAL.

How's your neck tension?

 

[Walkalong]

The bullet can move based on the shape of the crimp groove. I do not try and move a bullet after crimp because the crimp is supposed to prevent it.

Agreed, make the case mouth roll into the deepest part of the cannelure or the crimp groove in a lead or coated lead bullet, and that's your OAL, even if it changed a couple thousandths after being seated. Matter of fact, it is is, making that your pre-crimp OAL might alleviated it. But it isn't hurting anythin if the crimp ends up right.

 

[Bazoo]

Agreed, make the case mouth roll into the deepest part of the cannelure or the crimp groove in a leador coated lead bullet, and that's your OAL, even if it changed a couple thousandths after being seated. Matter of fact, it is is, making that your pre-crimp OAL might alleviated it. But it isn't hurting anythin if the crimp ends up right.

View attachment 1182509View attachment 1182511View attachment 1182512View attachment 1182513

That is some darn beautiful crimping and cartridges. What brand of crimping die do you use? Did you seat and crimp in the same step there?

 

[Walkalong]

Various crimp dies, RCBS seaters, Redding Profile Crimp dies, Hornady seaters, etc.

One of the main things is trimming cases and bullets with good cannelures and crimp grooves.

 

[Charlie98]

I do not try and move a bullet after crimp because the crimp is supposed to prevent it.

I don't go back, but I might adjust my seating depth to compensate if it mattered to me.

That... and that... +1

 

[buck460XVR]

Crimp to the center of the cannelure/crimp grove and move on. I never even measure my OAL after the bullet is seated for revolvers. Re-seating it back .005" is not going to do anything but maybe compress the soft point/hollow point on the bullet, if it has one. Not gonna affect pressure to the point of being unsafe, nor is it going to increase accuracy, but may only work the brass more. How heavy of a crimp are you using? How much flare are you putting on your cases? Are you using a Lee FCD?

 

[FROGO207]

There are so many other factors that affect accuracy other than bullet movement while crimping. That little difference would not bother me. As others have said set crimp to be at deepest part of bullet canula crimp and be done with it.
FWIW I don't roll crimp anything that I can get away with not crimping as I feel crimping degrades accuracy to a point. Everything else I taper crimp as minimally asI can get away with.

 

[Rule3]

, I've noted that when I seat to the proper depth (and verify that with a mic), after crimping, it will "squeeze" (for lack of better terms) the projectile back out a bit. Typically a min of +.005", upwards of +.010 OAL".

has anyone else noted this?

Which is why when you set your seating depth and are going to crimp with the same die, you should add on .005 or whatever. Then after crimping it will be the COL that you want.
You should not then re seat as it will mess up the crimp (if are allowed to use that word anymore)

Actually got that info from the original Richard Lee when speaking with him. He was a good guy!

 

[Walkalong]

Agreed, make the case mouth roll into the deepest part of the cannelure or the crimp groove in a lead or coated lead bullet, and that's your OAL

Crimp to the center of the cannelure/crimp grove and move on. I never even measure my OAL after the bullet is seated for revolvers.

As others have said set crimp to be at deepest part of bullet canula crimp and be done with it.

Sounds like a consensus.

 

[coondogger]

I don't go back, but I might adjust my seating depth to compensate if it mattered to me.

This.

 

[murf]

With pretty much any straight wall round that I load (38 spcl, 44 magnum, 460 S&W, projectile doesn't matter, they all do it the same way), I've noted that when I seat to the proper depth (and verify that with a mic), after crimping, it will "squeeze" (for lack of better terms) the projectile back out a bit. Typically a min of +.005", upwards of +.010 OAL". If I then place it back in the seating die, it will seat it back properly (without effecting the crimp). I run Dillon and Hornady dies for these rounds, doing seating on one die, crimping on another. This happens on both my Dillon 550 and RCBS single stage.

has anyone else noted this?

no, but I bet if you trim your cases all to the same length, your "problem" goes away.

Cudos for using a separate crimp die,

murf

 

[J-Bar]

The only thing I do after crimping is spot check them in a cartridge gauge to make sure they will fit the chamber. I gauge each round if I plan to use them in competition. I know some folks do a plunk test in chambers but I prefer a gauge; call me crazy.

The gauge catches that one round in two thousand whose case splits during seating and that I don't see as it indexes to the crimping station (Dillon 550).