Deluxe Quick Trim keeps cutting too short?

[sillyburt]

New poster here. I've got the deluxe quick trim die and cutter for 380 ACP with power attachment. I won't lie and don't have a lot of experience reloading so perhaps I'm doing something wrong here. I have the die in the Lee APP press. I have the collar set to the longest length (.680) but it keeps trimming to .672 +/-.001 with the occasional .675 or so thrown in the mix. I'm chocking that up to chips in the shell holder.

I tried setting the adjustment collar to trim shorter and it did so it's not like I had that set wrong. Is it possible I ended up with an undersized die? I was considering calling Lee and asking for the dimension so I can verify. I'm also considering ordering a shim (.008) to put under the trimmer as I think that would fix the issue but I'm also trying to see if there's anything else I could be doing wrong. The cutter length is consistent.

Another consideration is the Lee APP shell holder is not the same thickness as the regular shell holder. I could set up a single stage press to double check that scenario. However I really wanted to use the APP press as it would make trimming lightning fast.

Any insight or suggestions would be helpful

[GasGuzzler]

My money is on the shell holder. Wouldn't take much to prove it by using a regular press a couple times.

[Ohio3Wheels]

My money is on the shell holder. Wouldn't take much to prove it by using a regular press a couple times.

Make smoke

[sillyburt]

I checked against the regular shell holder in a single stage press. It only got shorter.

I emailed LEE they basically said if it cuts within SAAMI specs regardless of how I'd like to set it then it's doing its job. I've read and seen reviews that have showed it to be spot on but mine's not close.

I also tried the 9mm die I bought. That also cuts short. I guess the tolerance of the die (collet) length is why they give you the length adjusting ring...I figured it was for you to be able to dial in your length within the SAAMI spec. From what they keep telling me it's more to get you into that spec

Since both dies cut short (.008 for 380 & .006 for 9mm) I think the cutter itself is part of the culprit.

[Ranch Dog]

Thanks for the information. I've not used the QT, just the standard cutters, and they are easy to adjust to a specific length.

[horseman]

.680 is the -MAX- case length for 380 brass. The trimmer is designed to cut to a "trim to length" of .672. The trimmer is doing it's job corrrectly. Normal "trim to length" is maximum case length minus .10 for "most" cartridges but the 380 is a bit less as noted. You're fine.

[cj8281]

I had a similar issue with my .223 trim die. I made a .010 shim that I installed on the cutter and it fixed my issue. Another thing you can try is setting up your die with a shim between the shell holder and the bottom of the die body and see if that works for you. Honestly, I don't ever trim pistol cases, just rifle.

[Macd]

This post brings up an interesting question. What happens if a rimless straight wall cartridge which spaces on the case mouth is trimmed short even if it is only to SAAMI minimum specs. Your pistol will answer that question. If you are getting light strikes, misfires or flattened primers when you know you are within safe pressures your chamber may be toward the max length and the case toward the minimum. I have a mil-surp Browning that doesn't like short cases.

[Cdog]

I know this thread is a few months old, but I'll throw my $.02 in.

In 35+ years of loading I've never trimmed a straight wall/semi straight (9mm) case. Each time a round is retrieved from the magazine the case is slammed inside the chamber. Headspacing off the case mouth means the case mouth is pounded back upon chambering. I let autoloaders shorten case length on their on.

[Ranch Dog]

I know this thread is a few months old, but I'll throw my $.02 in.

In 35+ years of loading I've never trimmed a straight wall/semi straight (9mm) case. Each time a round is retrieved from the magazine the case is slammed inside the chamber. Headspacing off the case mouth means the case mouth is pounded back upon chambering. I let autoloaders shorten case length on their on.

Sounds reasonable.