Author Topic: Interference in the expander/primer stage  (Read 9538 times)

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johnfreeman

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Interference in the expander/primer stage
« on: April 27, 2014, 09:59:47 am »
My 45ACP reloads are coming out overly expanded (will not feed reliably in several handguns  and will not pass a go gauge.)
After the sizing/deprimestage, they're fine, after expanding, not fine.  If I back out the expander plug more, it'll interfere with the powder slide. The issue is not with the neck, but with expansion of the diameter near the base.

What should I look at (and then adjust  8)  ) next to address this problem?

Thanks
John
« Last Edit: April 27, 2014, 10:05:05 am by johnfreeman »

fc60

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Re: Interference in the expander/primer stage
« Reply #1 on: April 27, 2014, 11:10:55 am »
Greetings,

Are you able to post photos of the expander plug and "deformed" brass?

Meantime, what is the diameter of the expander plug?

What bullet are you seating?

Does this happen with all brands of brass; or, certain brands only?

Cheers,

Dave

johnfreeman

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Re: Interference in the expander/primer stage
« Reply #2 on: April 27, 2014, 11:21:51 am »
Hi Dave

I'll go measure the expander plug. I believe it to be a stock Star unit.  This happens independent of brass types and with several bullet types.

The bullets I'm using are plated Berrys 230g RN  + some home cast 200g SWC out of a Lee mold, that have been powder coated and sized after powder coating in a Lubesizer (Star). Dia is .452 (I will double check that too)


rbwillnj

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Re: Interference in the expander/primer stage
« Reply #3 on: April 27, 2014, 05:01:29 pm »
If it's the machine I'm thinking of, you have a separate taper crimp die.   Make sure you are not crimping the case in the seating step.   In the seating die you should take out any flair caused by the expander, but there is not need to crimp the case in that station.   If you over crimp in the seating station you can cause a bulge in the case which will have an adverse effect on feeding and function.

To adjust the depth of the seating die, I take a sized case which has not been expanded, place it in the seating station, and with the tool head in its lowest position, adjust the seating die down until it touches the case mouth, then back it off slightly.   You will of course have to adjust the bullet seating depth after making this adjustment .

This method of adjusting the seating die only applies if you have a separate crimp die.

Bruce
« Last Edit: April 27, 2014, 11:57:18 pm by rbwillnj »
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johnfreeman

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Re: Interference in the expander/primer stage
« Reply #4 on: May 04, 2014, 08:17:44 pm »
Thanks for all your suggestions. I've been messing with the various stations and a cartridge case gauge and figured it out. The problem is, there's an incompatibility with the taper crimp die and the case kicker I'm using. I need about a 32th of an inch more travel than that case kicker allows, in order for this to work.

I'm disappointed as the kicker works great.,... it's just incompatible with the dies I have in my Uni .

Welsh Rifleman

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Re: Interference in the expander/primer stage
« Reply #5 on: May 04, 2014, 10:20:04 pm »
I believe that most of the time, you need to use a taper crimp die that has been modified "shortened" if you are using a mechanically operated case kicker....or it will hit the case kicker mechanism before the bottom of the stroke.  I always prefer to use taper crimp dies and my 38 spc/45 lc/44 spc and 45 acp taper crimp dies are all modified as described.

Dave Wilson (fc 60) modified three of these and they work great.  His email address is posted.

George (aka Welsh Rifleman)
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johnfreeman

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Re: Interference in the expander/primer stage
« Reply #6 on: May 05, 2014, 06:35:18 pm »
I'll get with Dave to see if he can "fix" that die for me. The kicker works fine, but not with the taper crimp in that last station.

To wrap up this problem  learning experience. What LOOKED to me like an interference at the base of the casing was in fact interference at the mouth of the case. By a combination of  measuring factory ammo, measuring the ammo that didn't feed, and the loaded case gauge , and a lot of caliper measurements I finally found the root cause.

The benefit is, I know far better how each stage affects the case sizing having done before/after measurements at various stages. 

Thanks to all for the hints... and I learned more about my Stars...and Dave is building me a new die to fix this.
« Last Edit: May 17, 2014, 06:50:17 pm by johnfreeman »