Where does the brass go?

[Link]

from your primer pocket when they get loose? Could it be that it flows outward from a slightly oversized chamber at the head end? I have gotten loose pockets after about 4-5 firings with no signs of pressure in my 6BRA but my 30 BR brass lasts forever. . This might be a stupid question but I'm wondering why.
TY Don

 

[Rocketvapor]

LR primer diameter is about 0.211".
A half thousandths and it will be loose.
The base of your cartridge is more than twice that (over four times the circumference)
Base expands by a tenth or two (0.0002") and your pocket could end up loose.
Pressure SIGNS might not be a good indicator.

 

[Hohn]

By the time you have visible pressure signs, you are above the pressure that will kill most primer pockets in several cases.

 

[DaveTooley]

from your primer pocket when they get loose? Could it be that it flows outward from a slightly oversized chamber at the head end? I have gotten loose pockets after about 4-5 firings with no signs of pressure in my 6BRA but my 30 BR brass lasts forever. . This might be a stupid question but I'm wondering why.
TY Don

How and what do you use to interpret pressure?
Every lot of brass, even the same caliber, has a different yield strength.

 

[Twicepop]

I read an article a while back about what criteria to use for determining if a load is over pressure. The guy wrote that when load developing with virgin brass he measures the web diameter right above the extractor groove. These are then measured after the firing and any expansion up +.0015" is acceptable, anything over that is beyond safe pressure levels.

 

[Uncle Ed]

Simple Trick for Monitoring Pressure of Your Rifle Reloads
http://www.hodgdonreloading.com/rel...-trick-monitoring-pressure-your-rifle-reloads

One of the first rules of handloading is to always follow the approved reload data. The cautious reloader gradually works up to approved maximum loads to ensure his particular gun does not show pressure signs. Generally this is visual observation of the fired shell case head and primer. There is another slick way to check for pressure signs if you are interested.

Using a blade micrometer that measures in ten thousandths (.0001"), new, unfired cases can be gauged before and after firing to determine reasonably accurate maximum loads. Micrometers measuring in thousandths (.001") are insufficiently accurate to perform these measurements, and should not be used. Previously fired cases cannot be used accurately due to various levels of brass hardening. Measurement is taken just ahead of the extractor groove on the case head and must be taken at the same place on the case before and after firing. By placing a small mark on the case head – entering the cartridge in the chamber with mark at 12 o’clock – a consistently accurate measurement can be taken with each firing.

Lower pressure rounds, like the .30-30 Winchester, usually yield maximum pressures at .0003"-.0004" expansion. Modern cartridges, like the .223 Remington, will show maximum pressure at .0004"-.0005", while .308 Winchester, .270 Winchester, etc., typically yield .0005"-.0006" expansion at max pressure. Magnums, like the .300 Winchester Magnum, show maximums at .0006”-.0007” expansion, and should be measured on the belt.

In conjunction with these measurements, case head signs of pressure should be monitored as well. These signs include very flat primers, slightly cratered primers, ejector marks on the case head, and stiff extraction. All these case head signs indicate high pressure, and loads should be reduced until these signs disappear.

As always, start with the beginning load listed, and cautiously work up to the maximum shown for that set of components, using the methods listed herein.

 

[Link]

How and what do you use to interpret pressure?
Every lot of brass, even the same caliber, has a different yield strength.

I read the primer dent from the firing pin, roundness of the outer edge, ejector marks, head smear and bolt lift of click. Then loose primer pockets lol

 

[D-4297]

I was a tool & Die guy for close to thirty years , and I'll let ya in on a secret . Brass is a little like water . It flows where it gets pushed , only with brass , you have to add heat and some form of compression or expansion . Just plain old physics .

 

[Old Navy]

I would extremely upset if any of my Lapua brass only lasted that long.

 

[Liven The Dream]

There is a Engineer Barrel Maker in the PNW that made Dies to flow that Brass back to it’s place ??
I can PM info ?

 

[dogdude]

Don-''Link''. I'm betting your fireform load was to Hot..ask me how I know

 

[243winxb]

Loose pockets in 5 firing or less, reduce powder charge. Case head is expanding a small amount at each firing.

 

[Link]

Don-''Link''. I'm betting your fireform load was to Hot..ask me how I know

OK How you know :}

 

[243winxb]

Someone makes a pocket tool, no and no-go to check pockets.

 

[CaptnC]

Hornady brass has got to have the worst reputation going but I have 6.5 Grendel cases that I have fired so many times it hard to read the head stamp any more...yes most of the time when I loose a piece, it because of a loose primer pocket. I have 4 AR's chambered for this round and because I had little to no experience loading for gassers I only load to velocity to keep from over pressuring the platform.

So brass life brass been incredibly! I have about 35 cases left from my original 50 that I started with, with my first Grendel. Most lost the pocket...one had case head separation and only two split necks...the remainder either lost pockets or were used as hunting brass that were never recovered (only a few).

But for sure the death of case life is over pressure!

 

[searcher]

That Grendel cartridge is pretty hot when loaded to "factory" velocities. Get those babies warm at all and you might lose a piece of your bolt as I have done twice. I have never done that with any other A/R caliber in many tens of thousands of rounds. Back it off and everything is wonderful.

 

[Link]

Thought of a question, would a slightly oversized chamber let the brass at the head flow and cause loose primer pockets?

TY