crimping cast .45acp

[ted_dent]

Ok so is the crimp even necessary on this bullet then?

You need some crimp to remove the flare put on the case mouth by the expander die. If you don't remove the flare the round will jam in the chamber. Since this bullet has no crimp groove you definitely want to put some crimp on the bullet to prevent it from moving under recoil. All the flare should be removed plus 1/4 to 1/2 turn more to ensure a secure case grip on the bullet.

As "cooey43" has noted, the proper crimp to put on a straight walled, rimless case like a 45 ACP (and 9mm, 40 S&W, etc.) is a taper crimp, not a roll crimp.

 

[Standardvel]

I crimp my light target loads so the mouth of the case measures about .462-.464, a heavy crimp helps with power burn with light loads and prevents bullet setback during feeding.

 

[ted_dent]

I do not reload for handguns, so maybe out to lunch - but some "bullet pull" needed to let the burning powder build up pressure - even in handgun cartridges? Straight cases need a shoulder (case mouth) to allow the firing pin to strike, without whole case sliding forward and away - was my impression why tapered, not rolled, crimps were used. Maybe I have that muddled up - will not be the first time ... OP is talking about a 45 ACP, which I think is a "rimless" case?

You are correct.

 

[zuke]

The 'fingers' are only in the Lee rifle factory crimp dies. The Lee pistol FCD uses a carbide ring.

Thanks for clearing that up.

 

[dearslayer]

You need some crimp to remove the flare put on the case mouth by the expander die. If you don't remove the flare the round will jam in the chamber. Since this bullet has no crimp groove you definitely want to put some crimp on the bullet to prevent it from moving under recoil. All the flare should be removed plus 1/4 to 1/2 turn more to ensure a secure case grip on the bullet.

As "cooey43" has noted, the proper crimp to put on a straight walled, rimless case like a 45 ACP (and 9mm, 40 S&W, etc.) is a taper crimp, not a roll crimp.

As per the Lee instructions I turn it down until it touches the case mouth then with case removed I turn it down just a hair less than another half turn.

 

[B]

As per the Lee instructions I turn it down until it touches the case mouth then with case removed I turn it down just a hair less than another half turn.

Which is fine... Keep in mind guys who don't even know how the FCD is built or works are commenting... They don't create a roll crimp, it's more of a step. You don't need any cannelure or groove, the FCD will do the work.

 

[mmcintyre1220]

I do not think the Lee Factory Crimp Die requires or uses a crimp groove in the bullet - perhaps you are thinking of a "roll crimp"?

It does not however, if the die is a c hair down too far and its not engaging the mouth it will actually bevel the mouth outwards unless there is a crimp groove

 

[dearslayer]

In your pics it looks like a roll crimp ???? In my 30 yrs. I have always used a TAPER CRIMP on .45 acp
with no issues.

Not sure how it would be a roll crimp . Is that even possible with the 45 FCD that came with the Lee die set of 4?

 

[zuke]

When I set up my Loadmaster I used the roll crimp die to remove the flare and used the FCD just under the .452dia so there's a nice slope for snag free feeding.
I load cast LEE TL452-230-TC in my 45 Win Mag M1-Carbine conversion

 

[dearslayer]

Perhaps I'm not setting the FCD correctly? I'm finding some of the responses confusing but only because of my lack of understanding.

 

[zuke]

Re-read the instruction's. Set up 1 die at a time so you understand what it does, and how it does it, then set the next die. Go to youtube for a visual.

 

[dearslayer]

I've gone over the instructions and watched lots of videos. I've never questioned it till now with the cast bullets. I do believe I have it set properly but thought that perhaps it's possible that it's hitting the lead edge of lead bullet instead of the case mouth thereby creating an error. I'll have to mark it with whiteout as suggested earlier to see what's actually going on. I wish there was an animated video on how it actually works.

 

[VICIOUS]

HI stranger. Looks like the Lee fac. crimp is a bit down to far. Make it" look" like a roll crimp but the lee FCD is what I call a squash crimp as they are supposed to look like a factory crimp.
Brass length variation can make things seem off and the thumping going into the die and back out can be thickness of various brass. It is all good as that is what a Lee FCD is designed and does best, smooth out the lumping load so they will chamber OK.
Most 45 acp bullets do not nor need a crimp grove. A soft crimp to .472 at the top of the loaded brass case is good. Take loaded round and push the nose of the loaded round by hand against the work bench. Did the bullet push into the case? At the club measure the COL. Load it in the second round into the mag. Fire the first round and eject the second and measure the second round. Did it push into the case? Mine sometimes will be a few thousands shorter after cycling into the chamber, all is well.

 

[ted_dent]

I've gone over the instructions and watched lots of videos. I've never questioned it till now with the cast bullets. I do believe I have it set properly but thought that perhaps it's possible that it's hitting the lead edge of lead bullet instead of the case mouth thereby creating an error. I'll have to mark it with whiteout as suggested earlier to see what's actually going on. I wish there was an animated video on how it actually works.

The main thing to remember with a taper crimp die or a FCD is that you do not have to really squash the case mouth down into the bullet. As long as you remove the expander die flare and compress the case mouth a small amount the rounds should chamber without any issue. If it feels like the die is really bearing down on the case mouth you are putting too much crimp on it.

 

[ted_dent]

Perhaps I'm not setting the FCD correctly? I'm finding some of the responses confusing but only because of my lack of understanding.

It sounds like you have set the die up properly. However, 1/2 turn of the crimping stem may be more than you need. If it looks excessive back it off so it's no less than 1/4 turn but not as much as 1/2 turn.

"VICIOUS" makes a good point. Since handgun cases almost never require trimming there will always be slight variations in case length. Since the die applies the same amount of crimp to each case, the crimp on a case that is a little longer will be more pronounced than on a case that its a little shorter.
However, unless something is seriously amiss as regards the length of the case the difference is only cosmetic and will have no real effect on feeding or accuracy.

 

[barsik]

depending on the gun, some rounds will headspace on the extractor.

 

[dearslayer]

Well I've loaded and shot about 200-250 rounds and only had 2 jams if I remember correctly, so it cant be all bad. I just thought something was up just because of the jump going into the die. I'll back the crimp off 1/4 turn to see if its changes anything.

 

[DANS40X]

depending on the gun, some rounds will headspace on the extractor.

Not by any design that I'm aware of.

Case mouth, rim,shoulder,belt,but not the extractor.

Yes one could run 40S&W thru a 10mm chamber, but do not ##### when the extractor chips or breaks.

 

[B]

Not by any design that I'm aware of.

Case mouth, rim,shoulder,belt,but not the extractor.

Yes one could run 40S&W thru a 10mm chamber, but do not ##### when the extractor chips or breaks.

Not by design but some well used cases can shrink to the point where the extractor is doing the work. That is something I have only read about, never experienced it myself. Not that I would likely notice...

 

[alpining]

.... I'll back the crimp off 1/4 turn to see if its changes anything.

Can't hurt, let us know what you find.