.30 carbine chambering problem not resolved

C

condor bravo

New member
This is a follow up to a previous thread outlining the chambering problem with a new .30 Inland carbine and reloaded ammunition. I have now definitely determined the cause of the situation but the solution still waits to be found.

First a review of some of the contents of the previous thread.
Most everyone supported the likely cause of the situation on a tight chamber. A two die sizing setup then was then used with a steel die that sized the base slightly more than a carbide die and the carbide die was then used in station two for some additional sizing on the case body. This put the sized cases well within specs and is no longer considered to be part of the problem. Previous OAL had been set to 1.68 per Lyman manual. Factory Federals and Armscores mike at 1.65 so I cut the reloads down to 1.65. I later obtained a Wilson case length die and all dimensions are as good as can be.

So what is the problem then? I earlier mentioned a few times that circular copper rings would extract from the chamber during a chamber cleaning but didn't think much about that to begin with. However the copper rings have become more pronounced, clogging the chamber, and is definitely the culprit. Thinking that the plated bullets were soft and deposited the rings, I was confident that FMJ bullets would be the cure I ordered and received 500 110 gr Sierras.Well, wrong again. Same deposits with the FMJs. After cleaning out the chamber, only one or two rounds can be fired before the next failure to chamber and another cleaning is required. It's not known whether the rings are deposited when the round chambers or after firing.

However the carbine does chamber and fire factory ammunition fine without leaving any copper rings or traces of copper residue. Any observations here or suggestions other than keep using factory ammunition?
 
To much crimp?
May cut off a bit of case mouth, leaving it in the chamber.

When you over crimp, there may be a bulge formed, just at the case mouth. This will let the round chamber only part way. The action will not close.
 
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I can try. But I'm guessing in the dark,because the info is a bit thin.
Assumptions:
If it was a brass ring,you would have said brass.
The "copper" is either bullet jacket or copper plating,but the origin is bullet.

A guess,the "ring" is approx. bore/bullet dia? (please confirm)

My theory:
Factory loads work.
Lets look at reloading process.
Brass is harder than copper.Brass can cut copper.
The brass,for neck tension,is sized smaller than the bullet.
If the inside corner of the case neckis sharp,it can/will scrape bullet metal ahead of it.
This is problematic as the 30 carbine headspaces on the case mouth. The "shim" of copper ring interferes at the headspace level.

If that is right:

Jacketed bullets ,do you chamfer the ID of your case mouths? Please do! Alight chamfer,ID and OD is good practice. You might even try it with aVLD chamfer tool.Remove the cutting edge from the brass.

Plated bullets,are gummy that way.They really want to stack up on the case mouth.Some bell is in order.

One more possibility,crimping. If you are crimping and seating at the same time,There is linear motion of the bullet as the case is squeezed in.That will cause thecase mouth to curl a chip from the bullet.

If you must use a light crimp,do it as a separate step,and back off the seater stem.Don't push the bullet deeper as the crimp is formed.

With proper neck tension and a chamfer,loading jacketed bullets,no bell and no crimp should be fine.

With plated bullets,you may need some bell to not shave.Crimp just enough to reliably remove the bell. Significant crimp is unnecessary. You headspace on the case mouth.A LIGHT taper crimp or Lee FCD is probably OK.I'd avoid the roll crimp built into the seater die.
 
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I will assume that the rings are brass. When you trim your cases and before you bell them do you chamfer the inside of the neck and deburr the outside of the neck? If you don't then there is a brittle ring of cartridge brass that can be deposited after the round is fired. It only takes a few of these "trimmings to take up the slack in the chamber causing your chambering problem.

Try chamfering the cases inside and deburring the outside before belling them and seating the bullets.
 
I thought you also had problem chambering some factory ammunitions.

Anyway, don't mean to give you hard time, but why don't you fix the root cause of the problem? Sending the brand new rifle back to the manufacturer and recutting the chamber that is. The ship is taking in water. Perhaps it is more important to plug the hole in the hull than trying different pumps to bail out the water just to keep the ship afloat. M1 carbine is a battle rifle. It shouldn't need two sets of die to load its ammunitions. Besides its floating firing pin makes a tight chamber a risky proposition.

The copper ring in the chamber is likely from brass rubbed off the casing, because of the tight chamber. Do you flare the casing mouth before seating the bullet? Do you crimp to remove the flaring? Do your rounds pass the "plunk" test? It is very important the round to chamber without any felt impedance, especially so for rifles of this design.

-TL
 
It would be very good for the OP to determine is the ring is brass or copper. It could be either,it can't be both.The difference takes us in different directions.

OP,feedback,please.

The OP wrote "Copper" I chose to believe he was smart enough to know the difference.I am not there to look.
Bullet copper is feasible. I damaged the barrellocking lugs in a 1911 38 Super maybe 25,or 30 years ago using plated bullets.Copper scraped forward on the case mouth,effectively increasing case length.This prevented fully locking into battery,Close,but not quite.
Been there,done that,got the tee shirt with "copper rings",bullet scraping,and semi-auto headspace on the case mouth.

I certainly could be wrong,but ,regardless of the initial suspicions,maybe we blame the chamber AFTER a cerro safe casting is taken and a good micrometer tells us the chamber measures undersize.

The 30 carbine case/chamber is tapered.IF it was undersize,we would have a "stuck" situation,like the locking taper in a lathe tailstock,or like over-crimped 5.56 ammo getting stuck in an AR chamber.

OP,Brownells,Cerro-safe .Its a metal that melts at boiling water temp and precisely makes facsimiles to measure. IF you take the casting and it DOES measure undersize,you can mail it to your rifle manufacturer.

No disrespect to the OP,but I suspect the Manufacturer is better at making rifles than our OP is at making ammo(for now! We all start somewhere,I made the same mistake)

OP,is the mouth of your chamber dead sharp,or is the corner rounded a bit?
 
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Something my M-1 is sensitive to is the brass length which I haven't seen mentioned. What is that measurement? Double check that and you may even want to try some a little short.
 
CB

You might want to try this, should give you some answers,

Start with a very clean chamber,
load a half a dozen dummy rounds,
no primer or powder,
load to the spec's required for your rifle,
with several types of bullets you have.

Take these rds and carefully inspect them,
load into a mag,
chamber them via pulling the slide back and let the rifle chamber them,
inspect these loaded dummy rds for any marks, scrapes,
at the end of the case and bullet junction etc.

See if you have any of these rings showing up,
if so,
there may be a rough or out of spec chamber, causing the problems.

Would like to hear back on the results found.

Tia,
Don
 
Lots of good feedback here so I will reply to each one in order.

243winxb
Too much crimp?
Ii just enough taper crimp to remove the flare. I forgot to mention that I tried not crimping at all, thereby leaving leaving the case mouth slightly flared; .003 over case mouth diameter of taper crimped case. Rounds would chamber fine but the copper rings continued to form. I did that on the possibility that the crimp was shaving copper from the bullets but that does not seem to be the case.

HiBC
Yes I am definitely maintaining copper rather than brass. Easy to tell the difference. Origin is definitely the bullet. The rings are bullet/bore diameter. No I do not chamfer the inside of the case mouths so they are left squared away and sharp but a slight flare is used to prevent bullet shaving. The taper crimp is very light. I normally crimp and seat the bullets during the same operation. However I will try chamfering cases and eliminate any crimping.

243winxb
I don't do any chamfering on any reloads that include some 20 handgun calibers and 30 some rifle calibers. Always use a mild flare when one is needed which includes rifle loading with some cast bullets. Flare for the carbine cases is done by the Dillon powder die. I am opposed to removing the brass from the mouth of the cases since that would tend to put a knife edge ridge to the mouth.

ShootistPRS
I stick with the foregoing that the rings are definitely copper. By now I have removed a good amount from the chamber and there is no doubt we are looking at copper. Again, will try some chamfering before loading. But explain the reason for chamfering rather than flaring. How could it improve the situation?

Tangolima
I realize now that the chambering problem with the factory rounds was due to the copper rings building up inside the chamber. Every time after removing the rings, the factory rounds chambered perfectly. Usually only one or two reloads will chamber after a cleaning. Crimping and flaring previously discussed. Rounds chamber very easily after chamber cleaning but not sure if they would pass a plunk test, have not tried.

HiBC
Definitely copper, no doubt about it. Note that I used to use mostly cast bullets with the old military carbine, but thought the better way to go with the new Inland would be with copper jacketed. Currently have over 500 Sierra 110 gr FMJs and some 700 plated. And with about 2000 factory rounds, things are not yet desperate. If necessary, may end up using factory rounds with the Inland and reloads with the military. But don't really want to have to do it that way.

Jag2
Brass length :
Varies considerably and some trimming could be called for.
Once fired Armscore brass: 1.278 to 1.286 and 1.294 after sizing
Once fired Federal: 1.272 to 1.278 and 1.287 after sizing
Once fired Winchester: 1.278 to 1.283 and 1.296 after sizing
Once fired Remington: 1.275 to 1.281 and 1.293 after sizing
LC military pull down: 1.285 to 1.287

Lyman manual: case length 1.290 trim to 1.286. I've chambered numerous sized cases only and all have chambered perfectly. No indication that any have exceeded chamber length.

NVreloader
Yes, several times I have actually done exactly what you are saying with dummy rounds but nothing was revealed. With a clean chamber, all attempts to find something amiss have been futile. The dummy rounds feed and manually eject perfectly. No copper rings show up with this exercise. This would suggest that the rings form during firing.

Mr T
I do not chamfer rifle brass but instead flare the case necks with an M die for loading cast rifle bullets. I have pointed out the difference between the steel die and the carbide die. The steel die sizes an additional .001 at the base and the carbide die sizes the body of the case more than the steel so were used jointly. This was thought to be important when a tight chamber was thought to be the primary culprit. I no longer believe that it is. I likewise doubt that the chamber is shearing the bullets but instead occurs during firing. I agree that some cast bullets would be in order and will do that.
 
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"...don't do any chamfering on any reloads..." Bottle necked rifle cases must be chamfered and deburred. Hand gun cases get flared. .30 Carbine gets loaded like straight walled hand gun cases anyway. There is no chamfering on them.
"...A two die sizing setup..." Isn't necessary. .30 Carbine die sets are 3 dies. one if which is (or should be) a carbide FL sizer die, one expander die and one seating die. There's no need to use the steel sizer and the carbide. They're the same size anyway. A Carbide sizer does not size smaller than steel.
Mind you, you must check case lengths every time anyway. Haven't ever needed to trim .30 Carbine in the 40 or so years I've loaded it though. So it's highly unlikely to be the issue.
However, that's not the issue. Doubt it's case or OAL either. If it's copper(kind of hard to not tell the difference between brass and copper, by eye, for sure.), that copper is coming from the bullet jacket. There's no place else it can come from. Very much doubt the chamber is shaving the bullets or the case.
Load some cast bullets and see if there's any lead shaving from the cast bullets.
"...Sending the brand new rifle back to the manufacturer..." Isn't going to help. The thing works fine with factory ammo. Doesn't appear to be an online warrantee(Only one year, anyway.), but most places these days void warrantees with the use of reloaded ammo.
 
Have you checked if your bullets and seating die play well with each other,or pulled seated dummies of each type and looked for rings inside the cases?
 
jimmy
Yes I have done that with both dummy rounds and live rounds and again nothing out of place. Right now I'm sticking with the assumption that the copper rings occur during firing.
 
Would politely suggest you start by following common hand loading procedure and trim your brass. 1.290 is listed in several manuals as max case length.. This means after resizing. Then chamfer your brass. Would personally consider loading brass that was 1.296 as hazardous. Funny things can happen after the round is fired if your cases are too long.

Another possibility is forcing bullet into too small a case mouth, or off center seating. This can remove rings/partial rings of copper from the bullet, which normally should be able to be seen before you fire the round.
 
zeke
Yes I'm aware that some cases especially after sizing are beyond the 1.290 case length and should be trimmed to 1.287 or so, no less than 1.286. I do have the necessary collet for the Forster trimmer and the .30 carbine brass so there's no excuse for not trimming when needed. I've pointed out that I do put a mild flare on the cases and remove with a taper crimp. Do you have a reason to consider that chamfering is preferable to flaring and then remove the flare during bullet seating? I am opposed to chamfering since that removes metal from the case mouth and almost results in a knife edge ridge. I'm wondering if sometimes we use the terms chamfering and flaring as meaning the same thing.
 
I think there is a misconception over chamfering. You do not remove enough metal to knife edge the case mouth.
If you take a piece of steel,with a freshly ground square edge,,and drag it across your thumbnail,it will scrape a chip of your nail like a woodplane.
If you pick up a stone and round a .002 radius on it,it won't cut..So long as there is SOME chamfer,right at the point of contact with the bullet,the rest of the case mouth can be square.

My brother has a Dillon 1050,case feeder ,and a power trim station.I understand the Dillon bell feature.This press works extremely well,no issues loading 38 Super and .223.
I agree,trim,bell,crimp accomplishes the same goal as chamfer/deburr,at least to the degree"it works" in the Dillon. .No one at WW is chamfering and deburring factory ammo.
I'm skeptical of the plated bullets. That copper is just gummy. It might be your crimp scraping bullet metal as the bullet exits.

I'd use crimp to eliminate bell,but no more than that.

On the advice to use carbide dies: I understand a lot of folks successfully use them with the 30 carbine. Good for them!! But a carbide die uses a carbide ring and sizes the case straight walled. The 30 Carbine is a tapered cartridge.

Carbide dies certainly may produce useable ammo. Steel dies will not corrupt the design of the brass,and so they will produce better ammo,its just more work to deal with lube.

An "out thee a ways" idea.I still lean strongly toward an ammo issue vs a rifle issue. Its nuts to do something to the rifle to fix the ammo. It COULD be there is some CNC form of machining a 30 Carbine chamber other than a conventional chambering reamer.
A reamer has slight corner radii from the grinding wheel on all inside corners.
The reamer can't really produce a sharp cutting edge on a chamber mouth,for example. That's not true if the chamber is made with a boring bar in a lathe.

Its conceivable production methods could have left a sharp edge on a chamber mouth to leade portion of the chamber. I doubt it,just brainstorming.Dragging a pice of nylon stocking through there might feel something.So might a drafting pencil lead.
If you find a defect,you might talk with the mfgr.They seldom make just one defect. They may have experience and remedy.

But,IF you find such a flaw and the factory ,for any reason,is not an option,

Either a pull-through chamber reamer should wipe any offending sharp edge off,or a few rounds of fine fire lap ammo ought to clean it up.

But don't fix what ain't broke.

Try this. Buy 100 new Starline brass. Use 100 of your Sierra jacketed bullets,or buy 100 more of any brand name jacketed bullet(not plated)

Lightly ID and OD chamfer the brass. Load 100. Clean the chamber,then shoot them.

If you have no problem,the gun is fine.Don't "fix"t.Work on your ammo.

You might checkyour reloading dies for any copper rings
 
HiBC
That's a roger on all the above. I'll keep trying different components, like the Starline brass and other FMJ bullets, which keeps things alive with the hope that a definite fix will show up in the process. If not, we at least are all trying and that is appreciated. Yes I have checked the dies for any of the rings or other copper residue.

Here's one thing I haven't mentioned in detail. Sometimes a round chambers about all the way but not yet locked. With that a push on the operating handle will complete the chambering. But most of the hangups occur with the round only half way chambered and requires a tap with a mallet to dislodge and extract. The copper rings will then definitely be found in the chamber. Removing is done by using a 6mm cleaning brush attached to a cleaning rod and then wrapped with a cleaning patch. Then by inserting the rod in the chamber and twisting, the copper is dislodged wrapped around the patch in the form of rings.
 
I'm not clear with whether this definitely happens with quality jacketed bullets.
As in good,GI quality factory loads
That is what the rifle was built to run. If there is a problem with those, there may be some problem with the rifle.

If the rings and/or the problems come from the plated bullets,you have your answer. It may be bad that you have a bunch of lousy bullets,but that's not a rifle problem.

Maybe,you can find reloading technique to workaround the bullets,or,maybe not.

Those bullets are cheap,but bullets that don't work are a waste of time,powder,and primers. No fun,either.
 
I've found a source for LC military 30 carbine pull down bullets and will get a few. Perhaps the jackets will be an advantage over the commercial FMJs. Pats Reloading located in Ohio. $20 per 100.
 
My manuals list the max brass length on 30 carbine as 1.290, the trim to length as 1.280.

When I chamfer a case mouth, am referring to removing any burs and cutting a slight beveled edge (inside and out) on the case mouth, without expanding the dia. When referring to flaring, the case mouth is being expanded out ward by a plug/mandrel/whatever, which increases the dia to allow bullet seating.

For reloading a 30 caliber carbine am using an expansion plug, that slightly expands the case for some of the bullets length and "flares" the case mouth. Have to look at the make, but likely modified it. It may have been a plug used in Lymans universal expansion die.

In some reloading trials, not 30 carbine, actually made the interference fit with bullet too tight and seating the bullet produced a copper ring.

Have found Hornady 110 fmj's to produce excellent accuracy, when compared to others. Might have something to do with their exposed lead base. When trimming for Ruger single action, am only trimming slightly below the max case length.
 
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