45LC Case bulge... bad chamber?

[tacotime]

These .45 Colt cases are from a 1/2 grain below-maximum Lyman published 2400 load (for rifle, not from the Ruger/Marlin/TC section) and a 250gr boolit out of a Winchester 94 lever. Winchester brass. I wonder if the chamber has a wide spot in dimensions. No cracks seen in cases.

I wonder if this is common on the 94, because I saw a .357 case fired in a 94 and it shows a similar bulge. The Model 94 chamber entrance is ramped open slightly at the bottom where the round feeds from, so I wonder if all 94 chambers and cases may show this if rounds are fired with enough pressure.

I note that the same 45LC rifle using cowboy loads at 750fps or so, does not show bulged cases. I wonder if the heavier load expands the brass just stronger and for a longer amount of time, to cause the brass to "fire form" and exposes the wide dimension in the chamber?

What do you think about the bulge and the rifle?

[ddixie884]

Almost all lever rifles are chambered loose to aid with feeding. I think near max loads will result in some case expansion. A load a little below max may give a lot less case bulge.

[6bg6ga]

I think its ok and will full length resize back to standard dims.

[Outpost75]

Chamber is too large. Measure diameter of fired case at the bulge. Expect that it is over .485"

Load is probably too hot.

Dies size the brass too much. Measure your sized cases, expect they are smaller in body diameter than .475"

Look for an older STEEL .45 Colt, or .455 Webley sizing die, not a carbide die, and LUBRICATE the cases!

RCBS Cowboy dies work the brass less, but older dies before 1970s are better.

Or have a steel die honed to .478" for use with .454" bullets.

Be thankful you were not using old pre-WW2 balloon-head cases, as they would have FAILED!

Repeatedly firing to blow out and then excessively resizing the brass will work-harden the brass, setting you up for a KABOOM! when the poorly supported case head blows!

I had a Marlin 1894 Cowboy II in .45 Colt which did this and I had John Taylor set back the barrel, rechamber it to .45 ACP and rework the lifter to feed the shorter cartridges. Even with +P loads I get no case bulge in a normal .45 ACP chamber.

Attachment 257143

[CastingFool]

From what I have read, 45 Colt chambers are cut a bit larger than really needed. The cartridge performance would show an improvement if the firearm had a tighter chamber.

[tacotime]

Don't want no Kaboom!

By "too hot" do you mean only because of the chamber dimensions, not because of the load itself? (being below the maximum load and not into the Marlin/Ruger/TC loads and a good 1.5 below the maximum load used by Waters in a Model 94). Primers not flattened. No sticky extraction.

That load level shot very well. Since these are hunting rounds not plinking or cowboy rounds, very few will be used. What if I limit the brass to new cases or once fired cowboy cases? Most on hand are Winchester. Does that sound reasonable, even if I can't locate a larger sizing die?

The bulge is only on the one side. But maybe too far forward to be related to the flared area for feeding at the chamber entrance? If not due to the feeder, then apparently there is a random oversized area in the chamber. Will measure the case.

What about the factory .357 load showing a similar bulge in the same case location a different Model 94? Has anyone seen any bulges out of a 94 case before? Never did myself but I wasn't looking either because I didn't reload back then. Maybe I should check an old .30-30 case and see if it shows a bulge.

Thanks for the advice.

[Outpost75]

Too hot for the chamber dimensions. You are asking alot of the brass to expand that much and seal a sloppy chamber.

The .45 Colt, .44 Magnum, .357 were not designed for lever-action use. To make a cylindrical case feed reliably in a lever-action some dimensional compromises are necessary to make the cylinder rise up and turn the corner. The .32-20, .38-40 and .44-40, being tapered, bottlenecked cases, support the brass much better and don't have those feeding issues as the smaller front end enters the bigger chamber easily and the tapered cartridge fits the chamber walls well, sealing the chamber so that black powder fouling doesn't leak back past the case and get into the action.

The .30-30 and .32 Winchester Special also feed sllick for the same reasons, so no chamber bulge.

[Texas by God]

Trivia question- what company first chambered the .45 Colt in a rifle? Marlin, Uberti, or ? I dont know the answer- just saying.

Sent from my SAMSUNG-SM-G930A using Tapatalk

[hpdrifter]

I had a Rossi do that. I marked the case in the chamber where the feed ramp was. It always expanded at the feed ramp. Opened up too much.
Rossi replace the rifle.

[one-eyed fat man]

Too hot for the chamber dimensions. You are asking alot of the brass to expand that much and seal a sloppy chamber.

The .45 Colt, .44 Magnum, .357 were not designed for lever-action use. To make a cylindrical case feed reliably in a lever-action some dimensional compromises are necessary to make the cylinder rise up and turn the corner. The .32-20, .38-40 and .44-40, being tapered, bottlenecked cases, support the brass much better and don't have those feeding issues as the smaller front end enters the bigger chamber easily and the tapered cartridge fits the chamber walls well, sealing the chamber so that black powder fouling doesn't leak back past the case and get into the action.

The .30-30 and .32 Winchester Special also feed sllick for the same reasons, so no chamber bulge.

Kinda makes you think those boys in New Haven had it figured out a hundred and forty years ago. But then they weren't playing bowling with bullets dress up.

[tacotime]

So, do you think the 750-800 fps cowboy loads do not have enough pressure to fire-form the brass to the chamber and to show the case bulge in the same rifle? I might think the pressure from a cowboy load would still be enough to fire-form the brass. No?

Or maybe the brass on those not-bulged rounds was better? The bulged cases were Winchester (reloaded 1x from factory 750fps cowboy rounds) and the not-bulged cases (but at cowboy levels) were Magtech or Starline. Do you think the brass could be the difference between bulge or no bulge?

[Outpost75]

NOT a brass problem. A sloppy chamber and excessive case sizing problem.

[rking22]

I have a 45 Colt Win Low Wall trad hunter. The fired brass will let a .460 bullet drop right in! The chamber is huge in dia. I suspect your chamber is like mine, see what the id of the fired case mouth is. I neck size my brass with an odd die and shoot the .458 Gould bullet in my low wall. Was going to make a set of special brass from 7.62x54r but havent got roun tuit.I dont shoot it much other than to hunt on occasion so 20 cases would do me, for you not so likely. Kinda agravating that it is like that, mine didnt shoot "normal" 45 pistol loads worth a flip. Shoots the Gould quite well, cant remember group size as its been a long while. I still have several thou of case clearance even with the big bullet, but it cant wobble around as much in the chamber. Give yoirs a measure and see.

[cwlongshot]

I get same in one Marlin ‘94. My newer Cowboy dosent do it. So I agree generous chamber. I have shot some healthy RUGER loads pushing 300’s to 1600 to see it. Worst is brass probably won’t last as long. But I have had that rifle for over twenty years and a truck load of deer it’s harvested. Still working today.

CW

[Hickok]

Had a brand new Marlin Cowboy model in .45 Colt that did the same with all loads, from factory loads to cast loads.

Cases always came out looking like a pregnant guppie fish.

[MT Gianni]

Never use carbide dies in 45 Colt. https://saami.org/wp-content/uploads...sting-Copy.pdf See page 59. The second drawing shows a taper from .486" to .480" to .470". You can't form that with a straight die.
The good news is that brass is now sized for the base of that chamber.

[samari46]

Have Marlins in 357 mag and 44 mag, also winnies in the usual rifle calibers. Even with warm not hot loads in the 44 mag my fired cases do not show that rather large bulge in the case. I suspect that your chamber is overly large and your loaded rounds sit at the bottom of the chamber. When fired the top of the cartridge expands to fill the chamber. That's why only on one side you get the bulge. Frank

[44MAG#1]

A lot of chambers for the 45 Colt are cut to the older dimensions which is on the large size. I shot a 45 Colt SAA that a buddy had with light cowboy loads. The cartridges cases after being fire in the SAA would not go in my Ruger Vaquero. The cases fired in the Vaquero would drop in the SAA easily. Even with much higher loads in the Vaquero the cases would still drop into the SAA. My Uberti 45 colt does the same thing. NO HOT LOADS WERE FIRED in the SAA or the Uberti. Only LIGHT cowboy styled loads were. But the cases expanded to the point that they would not go into the Vaquero.
Have used carbide dies for years.
Some 45/70's do the same expansion signs even with more than safe loads.
This is just information I have given out.

[john.k]

There is also feature where straight sided cases need a small relief in the chamber so as to transition from angled upward movement to horizontal into the chamber .....without this small relief in the chamber wall ,the round would hang up as the bolt forced it in.....This is why the bulge is only in one side......Why are all the old Winchester cartridges slightly necked.?For this reason,and the 66 and 73 lifter is level with the chamber.

[tacotime]

I can see the chamber relief on the bottom.

The bulge is only on one side and does not run the full length of the case. But it still seems like the cowboy loads would still fire-form the case the same as the heavier load.

I will do some measuring.

What was the reason for not using carbide dies? Was it simply that they would likely size too small?