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LNL AP Jamming - help needed

2K views 6 replies 3 participants last post by  RCC 
#1 ·

Got a problem going on with my LNL AP and I hope someone can help. I've only had my AP for a couple of months so my experience is minimum. My first loads were 9mm and I didn't have any real issues. I did have to tweak the pawls just a smidge when it was brand new. A couple of weeks ago, I loaded up 50 rounds of 40 S&W without any issues. I've been on the road for a couple of weeks and tonight I resumed loading 40 S&W-this is when the problem began.

After the brass has been resized and decapped, I lowered the ram and right when the pawl contacts the index wheel to advance forward, the press jams and will not advance. Initially I thought it was a pawl out of adjustment. But when I raise the ram a little to where both pawls are furthest away from the index wheel, I cannot advance the index wheel or shell plate by hand at all. I can only reverse the index wheel maybe a ¼ of an inch. I clear all brass from the other stations so only the "just resized" brass is in the shell plate (post station 1). I cannot easily pull the "just resized" brass out-it is stuck in the shell plate. So my symptom is about 10-20% of all brass gets jammed in the shell plate just after stage one (resizing) has been completed. I discovered if I reverse the shell plate just a smidge so it snaps back into the detents, then run the brass back up into the resizing die and back out, then the shell plate will advance the brass to the next station.

I spent at least two hours troubleshooting:

- Confirmed pawls not binding

- Shell plate is not loose-using Highboy lock washer method

- Confirmed binding does not happen at same shell plate opening or index wheel finger

- Adequate (but not excess) lube between sub plate and shell plate

- Checked resizing die, spindle and decapping pin setup to insure primer is being removed. (Die just touches shell plate at TDC, and decapping pin is exactly 3/16".)

- Dismantle die and re-setup. (Hornady taper crimp set)

- Checked and cleaned Spent Primer Tube at subplate for debris and stuck primers

- Primer feeding is not interfering

- No pattern on brand of brass-this is mixed range brass


While troubleshooting, I ran about 150 pieces of range brass through the press (resize, decapping only) and about 10-20% of them will hang. But if I reverse the shell plate a bit, run the brass back into the die, then back out, it will advance. After I ran out of brass, I ran it back through the press a second time but this time only 5-10% jammed.

I'm stumped. Thanks all.

 
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#2 ·
It sounds like you are binding on primers that have not completely cleared the case and dropped down the tube, try screwing down your decapping rod a touch.
 
#3 ·
Thanks 312shooter. This was one of my suspicions early on which led me to check the length of the decamping pin. For a few times I did pull the shell plate so I could examine the jammed case in position and in all cases the primer was fully removed and there were no primers lodged in the spent primer tube.
 
#4 ·
There are a couple of things that will cause that - primers not being completely pushed out of the case like 312shooter said is one. Another is primers not being seated all the way in, and a third is a case that gets hung on the ejection stub and does not eject. When that happens it is best to remove the shell holder plate and see what the problem is. The worse thing you can do is try to force the ram. If you do that you will break a pawl and be down until you get a new one.
 
#5 ·
Thanks stev32k. I do get a few cases from time to time that hang on the ejection stub and I can easily bump them into the bin. While I was trouble shooting, I bypassed all stations including priming so I could absolutely isolate the point of the jam and in every case it was post resizing/decapping. I know this sounds like a primer not fully pressed out but I'm not finding that. I think I'm going to switch over to 45 ACP and see if the problem follows. If I'm good there, I'll go back and try some more 9mm.
 
#6 ·
Update:
Just got done loading 50 rounds of 45 ACP without a single issue. I'm going to loaded up the rest of my 45 brass (about 100 pieces) by this weekend. If I have no issues with them, I'll load up a bunch of 9mm then come back and try the 40 S&W again. Nothing has changed from last night to today except caliber and from small to large primers (in other words I haven't adjusted the press). I"m starting to think my problem is 40 caliber related; shell plate or dies, or maybe I got some funky brass. Going to look for some new .40 brass this week.
 
#7 ·
Final word:
Hornady called me and said they completed their tests on my #10 shell plate. They could not duplicate my problem. Even so, they are sending me a new plate plate instead of my old.

Before I sent the plate off for testing, I backed off my sizing die about 1/16 of a turn (even though it was just barely touching the shell plate) and ran about 50 rounds without an issue so it appears I may have solved my problem. Hornady was aware of my possible remedy but I wanted to have he plate sent in and checked out just in case.

Excellent service from Hornady! They paid shipping both ways, tested my plate within a day or two of receiving it, and express a desire to resolve my problem.
 
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