OAL On 9mm 125GR Lead Poly Coated Bullets

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RWIG
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I have been loading with Acme and Blue Bullet 125GR round nose bullets, and the only way I get the rounds to drop flush in my case gauge is to make the OAL around 1.060". I originally thought it was my Acme bullets diameter, sine they are a little on the fat side (.3565}, but even after running the bullets through resizing they still need to be seated at 1.06" to past the case gauge. I thought the blue bullets would be better since their diameter is .355", but once I started loading them, they didn't pass the case gauge until around 1.07". When I load my X-Tream jacketed bullets, I seat them at 1.10".

It seems all of my bullet settings are shorter than most other reloaders. My rounds are accurate and cycle in all my 9mms. I was wondering what others OALs are when loading poly coated 9mm bullets?
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LT USN (Ret.)
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Using Cajun Bullets RN 145gr (.355") I'm setting OAL at 1.135 +/- 3.

I had measured my commercial rounds and the ran the gambit from 1.090" to 1.145".

As long as you are not compressing the power I don't think it makes a difference. Will they ramp into the barrels of all your 9mm's at that length?
LT

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BentAero
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You mean like this:

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I fought with this same thing for months. Literally months. Then I finally stumbled onto what the problem was. (At least in my case...)

I had too much "flare" dialed into the flaring die. Even though it didn't look like it to the eye, it had too much of a widemouth.

It's kind of hard to explain... There's a lot of things happening nearly simultaneously; bullet pushed into brass, bullet doesn't want to go in, brass squashes juuuust a tiny bit, flare removal portion of die needs more dialed into it to overcome the few microns that it's too wide, which results in DEcreased neck tension, because the flare removal is overworking. And I'm talking such a minor amount you can't really tell the difference by looking at the flared brass.

With me so far? Yeah, me neither...

As soon as I backed off the flare die to the point of 'just enough' to get the bullet to stay put during rotation of the plate, (I'd have testified it wouldn't be enough) my case gauging problem was instantly solved. Less flare requires less flare removal. Having a straighter wall of brass pushes the bullet in straighter, tighter, and with zero 'crimp' (crimp is a misnomer term) marks on a pulled coated bullet. My rounds have more of a bulged-under-the-bullet, straighter look now and less of an hourglass shape.

Once I removed some flare, my finished rounds at the neck went from .380-.381 diameter, to .381-.382 diameter -and dropped in perfect. Yes, they got bigger, but the die was no longer distorting the brass.

I didn't come up with this myself. I was frustrated just like you and started The Google for solutions. That lead me to "neck tension" discussions by people far smarter than me. "Crimp" is nothing. Neck tension is everything.

Try it, maybe it'll work for you.
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RWIG
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Thank you very much for your sage advise! I did dial back on the flare and that seems to do the trick. I am going to open my other pack of ACME bullets soon, and I would love for the OAL to be at least 1.10".
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BentAero wrote: Tue Jul 14, 2020 6:17 pm I had too much "flare" dialed into the flaring die.
I reset mine a couple of weeks ago after talking to Mr. Google (that's one smart dude). I get less rejects on the case gauge tester, maybe 2-3 per 100 rounds made. And I can correct 1 or 2 of those by "recrimping" them.

Mr. Google also said, "NEVER, EVER, try to change depth on a crimped round!" It's recommended to pull the bullet, resize brass and start the process over again.
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Texas1911
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My Canik TP9SFX and SF both had very short leades in the barrel.

This caused me to have to seat bullets deeper than I wanted.

I sent the barrel to CylinderHone on Facebook, DougGuy over at Castboolits and he throated the barrel for me.

This solved the problem and allowed me to seat my .357 bullets out to a proper length. I've had Doug do half a dozen different barrels for me. He does damn good work.
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Jester560
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I am loading Summit City Bullets 147gr round nose to 1.140 I my SFx. I don't have a case gauge, I use the barrel out of my gun for the plunk test.
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