Fundamental issue with FART

[Foxbat]

I have been processing a lot of brass with FART, but only now started using that brass, as I depleted the immediate supply of dry tumbled one - still have plenty in storage.

I immediately noticed two issues. One - the bullets on my 1050, fed by Mr.BF would not reliably stay in place.

And two - there suddenly was a lot of very fine brass shavings all over the place: mostly in the shape of very thin rings.

After pulling my hair for a while, I found the culprit.

The wet tumbled brass has the forward edge distorted, with small burr forming both on the inside, and the outside of the case - the cross section looks like a T.

The inner branch of that upper horizontal area interferes with the bullet staying put during the process, and the outer one gets removed by the crimp die - hence the shavings.

On many rounds that ring would still be sitting around the bullet, so manual removal was required, otherwise I suspect it might jam on feeding.

Now, that brass was typically tumbled in FART for close to 2 hours.

The size of the T is significant: it adds about .006" to the wall thickness, which is normally around .010". You can very easily feel it with your finger.

I don't yet know how to resolve this, and I have plenty of dry tumbled brass still available, so I have time.

It seems clear that less tumbling time should reduce the ridges - how long do you tumble?

Have you noticed this effect?

[slavex]

I noticed a sharp edge on brass tumbled for more than 1.5hrs, so I only tumble most of my brass for an hour. I've also been told that tumbling without pins will stop this from occurring, which if you have really filthy brass that needs to have the outside cleaned for a couple hours, would be easy to do, then throw pins in for a 3rd hour to finish.

[Gooldylocks]

I only tumble for 45 minutes or so. Maybe an hour if it isn't quite clean enough. I haven't noticed any burrs on my brass though.

[Sarge]

I tumble 3 hours with pins. I have none of the problems you mention. I load on 650 with MBF and near as I can tell the process is unchanged at all

[Steve RA]

I've tumbled a considerable amount of brass with pins, for varying amounts of time, and have never noticed that either.

[noylj]

Ii assume everyone but me knows that FART is the Franklin tumbler?

[shakman]

I'm fairly new to the FART myself, but have already tumbled several thousand cases. I've not seen/experienced any of the things you describe. For reference, I do 9mm, .40 and .223. I also did a small lot of .45 for a buddy.

[Foxbat]

I'm fairly new to the FART myself, but have already tumbled several thousand cases. I've not seen/experienced any of the things you describe. For reference, I do 9mm, .40 and .223. I also did a small lot of .45 for a buddy.

Please try measuring the case wall thickness - on my cases there is a VERY noticeable ridge both ways.

[Foxbat]

I've tumbled a considerable amount of brass with pins, for varying amounts of time, and have never noticed that either.

That makes perfect sense, because tumbling WITH media is used to de-burr the parts. When doing it with no pins the cases bump into each other, distorting the case mouths.

[Bkreutz]

I don't use a FART (just wanted to say that). I use a cement mixer because I started cleaning with SS pins before the FART became available. My cleaning time is around 1 hour and the only time I have problems with the bullet not staying in place is when the case is split (the case doesn't stay expanded after going through the sizing die).

[GrumpyOne]

Ii assume everyone but me knows that FART is the Franklin tumbler?

I think the FART stinks...

[safeactionjackson]

I've seen the brass shaving before, but they weren't related to wet tumbling, went away after I adjusted how much bell was being placed on each case. I normally tumble for 2-2.5 hours, although rifle brass goes for 3 hours.

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Edited February 8, 2016 by safeactionjackson

[Foxbat]

I've seen the brass shaving before, but they weren't related to wet tumbling, went away after I adjusted how much bell was being placed on each case. I normally tumble for 2-2.5 hours, although rifle brass goes for 3 hours.

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With no pins?

For clarity - the presses have been perfectly adjusted for months, if not years, producing the same loads in tens of thousands of rounds. No issues at all.

The difference was not minor - suddenly, when I put in the first batch of the wet tumbled brass, the problems started. It was not minor issue, it was a major problem.

[safeactionjackson]

Yes I use pins, I double check to make sure nothing has loosened. I've had powder dispenser loosen up in the past.

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[ano]

Ive seen this once, not sure when and how it happens

[shakman]

I'm fairly new to the FART myself, but have already tumbled several thousand cases. I've not seen/experienced any of the things you describe. For reference, I do 9mm, .40 and .223. I also did a small lot of .45 for a buddy.

Please try measuring the case wall thickness - on my cases there is a VERY noticeable ridge both ways.

I always use the pins, so I wouldn't have a ridge because of that. I probably should have mentioned that in my original post.

[Beastly]

I've seen shavings on occasion,never did track them down fully.

I used ss pin media in a Thumler to round the edges of rifles cases trimmed with an RT1200. Never noticed the effect being described, in fact, I am using it to produce the exact opposite effect.

[Jimk60]

When I started loading coated bullets, I had to open up my flaring to keep form scraping the coating off when seating. Here came the brash shavings when I crimped. (Lee FCD)

When I added the MBF powder funnels, and adjusted the crimp accordingly, the shaving went away.

I have not had an issue with plated or FMJ's.

Oh, and I do wet clean with pins.

[Steve RA]

Foxbat:

Wasn't aware, from your original post, that you were tumbling without pins. I've tried it that way and didn't get the results you mention.

But, this certainly doesn't mean you haven't received those results.

[Foxbat]

Here are some pics. I tried the cases from different batches, all done on FART at different times, they all produce that. They all have burr on both the inner and outer edges.

[Foxbat]

One more picture, clearly showing the distortion to the edge, compared to the normal case.

[Steve RA]

Wow, haven't ever seen that before.

I have gotten the little rings when flaring the case mouth too much and then the seating die knocks it off as it - mouth of case - stuck out too far and the inside of the seating/crimp die knocked it off.

Never had a case mouth look like the one on the left in last pic.

If you have some pins you might try a load with them and see how they come out.

[Foxbat]

I think I will try two-prong approach. I will tumble a new batch for a shorter time with no pins, to see at which point the distortion sets in - I would rather not use pins on routine basis.

I will also tumble the distorted brass with pins, to see if they will remove the burr.

[Miranda]

...

does the tumbler have a speed adjustment?

what happens if you fill it only half way?

... or all the way?

the cases are being peened and that will happen from the start

so while time will certainly make a difference, it would be far better to find a way to lower

the force of whatever is doing the hammering/peening

slowing the tumbler is my first thought.

miranda

[Beastly]

I'm tumbling in a cement mixer without pins. This is a somewhat more violent environment than a FART/Thumler. I don't recall seeing that but I will look closer.