Confused? Yes, yes, I am!

[Mauser98]

I too have XTP HP. Ok seat to cannalure, I dont use a crimping die on .357, but, the Lee Seating die is supposed to crimp. OR,, should I use a Lee Crimping die also? I did on 45-70 govt?

Lee makes the Factory Crimp Die, or what ever they call it, if that is what you are talking about. I don't use one on any caliber I load, and have yet to find a need for one in my process. I don't have any experience with it, so I can't say if it lives up to their claims. Another here may have hands on experience with one, and could elaborate on their merits.

I crimp in a separate step, but use the same die, well actually an extra die I have that the seating stem just sits in the box. There is no need to buy an extra die though, you can split the steps with how the die is set up.

Crimping in the same step as seating is a little more finicky in the die set-up. Nothing wrong in doing it that way, but I prefer to perform them in separate steps. It's a bit slower, but I'm not in a hurry when loading, so to me it isn't a big deal.

To crimp in separate steps with the same die, I place an empty case in the press and raise the ram all the way up. Then, with the seating stem backed way out of the die, screw the die into the press. You'll feel when the crimping ring in the die contacts the case mouth. BACK the die out 1/4 to 1/2 turn and set the lock ring. Then it is only a matter of setting your seating stem to get the correct COL.

When you are ready to crimp, again back the seating stem out of the die a ways, and loosen the lock ring. Place a case (with seated bullet) into the press and raise the ram to the top. Slowly screw the die into press until you feel the crimp ring engage the mouth. Lower the ram to the bottom. Now, screw the die IN 1/8 turn and set the lock ring. Run the cartridge into the die and check your crimp. This may or may not be enough crimp, you'll have to experiment at this point. Compare some factory rounds to your rounds and try to emulate them the best you can. Crimping is somewhat of an art, as different loads can require different amounts of crimping. A load with h110/w296 likes a heavy crimp IME. Where as a mouse fart load may not need one at all, except to remove any belling if that step was performed. N110 seems to be fine with what I consider a medium crimp.

[John S.]

Thanks, yeah my lee seating die, is supposed to crimp too. When the bullet is seated to OAL, pull down hard on the press lever, and it is supposed to crimp in that extra pull strength. The extra "crimping die," seemed to crimp nicely on 45-70 cases, better than just the seating die. Was it necessary? Prolly not!

[crbutler]

COAL is something you will have to adjust to get function.

If the round is at minimum OAL that will be the highest pressure it will have (barring something like sticking the bullet out so far it jams in the rifling) and Max OAL is generally whatever SAAMI spec is for the cartridge. Going longer than what it says its tested at, as long as you are not over the design spec for the bullet is safe.

The other side of this is how much case are you taking up with the bullet. If your load is for a bullet with more volume in the case (ie the cannulure is more towards the nose of the bullet) then this will give you more pressure than another different bullet with the same weight. Its all an application of Boyle's law and the various gas laws that they told you about in Chemistry. This is why they say use the exact data- if you find a different brand of (say) a 125 gr bullet, it will not behave the same as what they did the testing on. It may be higher or lower pressures.

That being said, most are pretty similar. If you are knowledgeable, starting low and working your way up slowly works well. That being said, the Coonan has a heck of a lot more steel surrounding the chamber than any revolver, so I would be less worried about safety based on pressures with a Coonan than with the revolver.

Some of the manuals explain this in detail.

I have not used full Lee die sets, so I cannot comment on their max/min statements that come with their dies.

I doubt that they are any different than the others that crimp and seat in one die, however. Part of the reason for not doing it as one step is that what you are doing is pinching in the case at the same time you are pushing the bullet in. It may be minimal fractions of an inch, but it can cause some distortion of the bullet, which can result in lost accuracy. You will also find that unless all the cases are the same length (within a couple thousandths) your crimp strength will be variable, and this will also affect the accuracy of your ammo- its not dangerous unless taken to extremes (meaning variable crimp strength). The bullet is still being pushed in to the case further as long as the ram is moving if you are doing it as one step.

One thing that is kind of strange unless you think about it some is that handgun brass (actually anything straight walled, generally) usually shrinks when fired- I don't recall ever having to trim cases in a handgun, unless I am deliberately shortening them to get the same length for uniformity. Rifle brass (meaning anything with a shoulder in it) will grow. That will need periodic trimming.

[John S.]

COAL is something you will have to adjust to get function.

If the round is at minimum OAL that will be the highest pressure it will have (barring something like sticking the bullet out so far it jams in the rifling) and Max OAL is generally whatever SAAMI spec is for the cartridge. Going longer than what it says its tested at, as long as you are not over the design spec for the bullet is safe.

The other side of this is how much case are you taking up with the bullet. If your load is for a bullet with more volume in the case (ie the cannulure is more towards the nose of the bullet) then this will give you more pressure than another different bullet with the same weight. Its all an application of Boyle's law and the various gas laws that they told you about in Chemistry. This is why they say use the exact data- if you find a different brand of (say) a 125 gr bullet, it will not behave the same as what they did the testing on. It may be higher or lower pressures.

That being said, most are pretty similar. If you are knowledgeable, starting low and working your way up slowly works well. That being said, the Coonan has a heck of a lot more steel surrounding the chamber than any revolver, so I would be less worried about safety based on pressures with a Coonan than with the revolver.

Some of the manuals explain this in detail.

I have not used full Lee die sets, so I cannot comment on their max/min statements that come with their dies.


I doubt that they are any different than the others that crimp and seat in one die, however. Part of the reason for not doing it as one step is that what you are doing is pinching in the case at the same time you are pushing the bullet in. It may be minimal fractions of an inch, but it can cause some distortion of the bullet, which can result in lost accuracy. You will also find that unless all the cases are the same length (within a couple thousandths) your crimp strength will be variable, and this will also affect the accuracy of your ammo- its not dangerous unless taken to extremes (meaning variable crimp strength). The bullet is still being pushed in to the case further as long as the ram is moving if you are doing it as one step.

One thing that is kind of strange unless you think about it some is that handgun brass (actually anything straight walled, generally) usually shrinks when fired- I don't recall ever having to trim cases in a handgun, unless I am deliberately shortening them to get the same length for uniformity. Rifle brass (meaning anything with a shoulder in it) will grow. That will need periodic trimming.

I have had to trim straight wall 45-70 govt, every few fires too!

[Seismic Sam]

Thanks, yeah my lee seating die, is supposed to crimp too. When the bullet is seated to OAL, pull down hard on the press lever, and it is supposed to crimp in that extra pull strength. The extra "crimping die," seemed to crimp nicely on 45-70 cases, better than just the seating die. Was it necessary? Prolly not!

You should seat and crimp in separate dies, at least to begin with. Setting a die up to seat AND crimp requires a certain technique and experience that rookies have a very hard time mastering. I'd go over all the steps, and have before, but the bottom line is that you have to have the stem in the seating die dead nuts on (within 5 mils) and the die in the toolhead dead nuts on (within 2 mils) AT THE SAME TIME to get a good seat and crimp. If you change either setting, you have to start all over! While I can set a die to do that, I rarely bother, and just use separate seating and crimping dies. It's much less of a headache. So if I were you, I wouldn't be trying to get one die to do both to begin with.

[JJ]

Thanks, yeah my lee seating die, is supposed to crimp too. When the bullet is seated to OAL, pull down hard on the press lever, and it is supposed to crimp in that extra pull strength. The extra "crimping die," seemed to crimp nicely on 45-70 cases, better than just the seating die. Was it necessary? Prolly not!

You should seat and crimp in separate dies, at least to begin with. Setting a die up to seat AND crimp requires a certain technique and experience that rookies have a very hard time mastering. I'd go over all the steps, and have before, but the bottom line is that you have to have the stem in the seating die dead nuts on (within 5 mils) and the die in the toolhead dead nuts on (within 2 mils) AT THE SAME TIME to get a good seat and crimp. If you change either setting, you have to start all over! While I can set a die to do that, I rarely bother, and just use separate seating and crimping dies. It's much less of a headache. So if I were you, I wouldn't be trying to get one die to do both to begin with.

Or just use the same die, and do it in two steps like Mauser98 described. If you are working on progressive or Turret, you should seat, and crimp in separate dies. If you are workng on a single stage, the same die can be used for both operations, but in separate seating and crimping steps. If you are doing compressed loads, some extra care should be used in setup, to ensure the bullet does not creep out of the case before being crimped.

[John S.]

Gotcha! Thank you.

[Mauser98]

One thing that is kind of strange unless you think about it some is that handgun brass (actually anything straight walled, generally) usually shrinks when fired- I don't recall ever having to trim cases in a handgun, unless I am deliberately shortening them to get the same length for uniformity.

95% of my straight wall reloading I don't trim. When playing near max loads it's nice to have uniform case length to keep the crimps uniform. 357 and 44 mag are the only pistol case holders I have for my Sinclair trimmer. I had to sort through my brass stash to find cases long enough to trim, as many were near, or under trim to length.