Protruding rim in case gage

[F. Guffey]

I discard and cases that do not fit into my case gage after resizing a second try.

Not me; I measure before and again after and then? If I find a case protruding from the case gage after firing I suspect a long chamber. IF after sizing I find the case head is below the top of the gage I know I know I over-did-it.

If the case protrudes from the case gage the case after firing I know the case is longer than a go-gage length chamber, If I am curious 'by how much' I use a straight edge and a feeler gage to determine the length of the chamber from the shoulder/datum to the bolt face in thousandths.

I know how difficult it must be for reloaders that have case head space; my cases do not have head space.

F. Guffey

[Dufus]

You can use a paper clip to check the inside of the case for case head separation.

The seeing eye tells no lies. I use a borescope for suspect case inspections, among other things that a borescope is good for.

[F. Guffey]

among other things that a borescope is good for.

I was asked to help with with a few computer problems (someone stole the hard drive for a program), it did not turn into one of those moments like 'if you are so smart' things but they asked If I could help with something else. The shop built an engine, they did a great job but could not find an oil leak. I ask the mechanic where all the left over parts were? The mechanic very politely walked over, picked up a small box of parts, returned and then handed me the box. I looked, picked up a small short bolt and then handed it to him; I instructed him to install the short bolt, installing the short bolt will stop the leak.

POINT! They went to the tool room to retrieve a bore scope/camera, I showed them where the hole was and they asked; "How could that happen?"

I suggested the engine they removed was fuel injected and the engine they replaced it with had a fuel pump and carburetor. Back in the old days a few mechanics removed the short bolt and then replaced it with a long bolt to hole the fuel pump rod up when replacing the fuel pump.

Other mechanics removed the rod and packed it with heavy grease, but the engine had to be cool.

F. Guffey

[RileyMartin]

I finally shot all the rounds I reloaded and everything cycled through the rifle except for three rounds where the primers didn’t seat well and didn’t detonate.

I’m not sure how much value this case Gauge is anymore if a case can protrude out the top but still cycle fine.

[F. Guffey]

I’m not sure how much value this case Gauge is anymore if a case can protrude out the top but still cycle fine.

I have fired cases that protrude from the top of my 30/06 case gage by .011" after firing, before firing the cases protrude from the top of the case gage .009". The 30/06 chamber is .002" longer than a field reject length chamber.

In the perfect world the chamber is go-gage length meaning when fired the case should be flush with the top of the gage, After sizing in the perfect world the case would be .005" shorter than the height of the gage.

F. Guffey

[RileyMartin]

Thanks, I learned a lot from everyone's comments.

I'm processing my brass again and came across the same issue. However now I know why and how to fix.

I took a file and ground down the burrs and sure enough the rims sit nicely in the case gage. I guess the case gage can at least point out burrs that need to be addressed.

The brass cycled with the burrs last time but I am guessing that these burrs will affect the consistency of the brass and therefore accuracy.

I've attached before and after PICs as an example.

Out of 173 pieces, I have 30 with burrs that need filing.

Is there something wrong with the extractor on my M1 Garand causing these burrs that I need to fix?

Is filing down burrs a normal and expected process with preparing brass?

Thanks.

[F. Guffey]

Is filing down burrs a normal and expected process with preparing brass?

No, and I would not call those gouges burrs. It does not happen often but when I suspect something wrong with the case head I turn the case around and install the case head into the gage with the big end first.

F. Guffey

[Machineguntony]

A few weeks ago, I had the exact same issue and exact same question posed here.

This is the answer...

After extensive research and lots of talking to some very knowledgeable people, there is only one fix for the problem: roll sizing.

What happens is that the rim gets fatter from firing for various reasons. A sizing die will not resize the rim, even if it’s a full length sizing die. Actually, a full length sizing die may actually shorten the lifespan of your brass because it contributes to a broken shell.

I ended up buying a Case Pro 100 with dies and conversions for 308, 9mm, and 223. It came out to over $3000 total, with the auto drive and everything. So it’s not cheap. It’s a three month wait for the product, btw.

The relevant question is do you need to make the rim fit the case gauge again? The answer is maybe.

So I tested all my rounds in my magazine fed guns, and even with the fat rims, they all fed fine. No problems whatsoever. I went to the range this weekend with my M16, FA AR and AUG, and they all ran flawlessly with the fat rimmed ammo.

The problem comes with my belt fed guns. With the belt fed guns, which I shoot a lot of, the fat rim prevents the round from properly delinking from the M13 or M27 link. This is because energy is lost on the forward stroke due to the oversized rim. This means that there are lots of FTF and all sorts of other problems. When I shot a batch of roll sized cases that I obtained from a third party, the belt feds ran flawlessly (these roll sized cases fit flush into the case gauge).

On a side note, the only belt fed gun that flawless ran the fat rimmed rounds was my 240. That’s because the 240 is a beast both in design and manufacture.

So unless you’re running belt fed guns, I really do not see a need to worry about the rims being fatter than spec and not falling flush with the case gauge.

[JeepHammer]

While I never know if my customers are running belt fed, or even full autos, but I get virtually ZERO complaints about the rolled cases, and believe me I pay attention since I have a 100% money back guarantee! Cost me a crap load when something doesn't work, and rolled cases work!

Counting case feeder, drive, spare parts I'm about $3,000 into mine also.
Maybe a little more since I built a lift table and case feeder that supplies about 1,700 an hour.
Humping 5 gallon buckets of brass over my head got old quick, so I built a lift table, the machine run low so the case feeder is at a reasonable height.
For some processing, I use a motorcycle lift table for the same reason. Purchase price was cheaper than I could build it, and it's big enough & solid enough for processing machines to run on without wobbling excessively.
Just an idea if your processing is getting out of hand