44 Mag case bulge. Out of round chamber. ??

BeRock

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Hi All,

I have a full-stock Chiappa Mare's Leg -- or really a 12" barrelled 1892 in 44 Mag. I bought it for the challenge of a short barrel (it will do 3 moa). If an actual Winchester had been available, I would have bought one instead.

I've discovered a troubling issue. I'm reloading sub-sonic 240gr target loads with W231 and Ttegroup (I had it on hand). The fired (new) Starline brass has a slight bulge about .335" from the case head on one side only. Always the same side (basically up.... I can tell by the ejector mark on the primer). So I looked into it more. The fired brass (and the first box of aluminum Blazer) measures about .012" out of round at the case mouth consistently (the entire length of the case is similar).

As for the bulge, the warmest loads are worse, but we're talking only 8 grs of W231 for 1090 fps. At the bulge, it measures .020" out of round (I realize that technically, the actual "out of round" is half that, but I hope you get what I mean). The actual bulge is only about .002" or .003".

My questions:

Is this anything like normal?

Should I care? (Especially since I'm reloading -- I worry about premature head seperation). If I weren't reloading, I wouldn't care.

If it is a problem, how crazy am I to consider a re-barrell? (?? $ ??).

I've had it for four years, but only recently started shooting it. Forgot warrantee. I can't even find proof of purchase.

Thanks for reading.
 
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The backside of this chisel isn't the straightest thing in the world -- I just realize....

qBziov3.jpg
 
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Pics would be a big help. Is the case bulging out or does it look like is pushed in from the outside?

Bulge out. Just below the bulge, the case is very round.

I was just told that maybe the chamber bulged. It has only fired one box of aluminum Blazer and 55 subsonic handloads with LOAs of 1.60" (wouldn't cycle well) and 1.575". Since the case mouth is out of round, it makes more sense that it was made this way... I would think the head end of the chamber (don't know the term) would go out of round more than the case mouth end if it were damaged from over-pressure. But what do I know? It's bad reaming or it was damaged during proof firing.

I do have telescopic bore gauges. I'll see if I can get one in there.
 
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I'd need a bit more data to add much to the discussion.

But consider:

44 mag brass is pretty tough, it takes a pretty stout load to expand the brass to seal the chamber.

I just happen to have some fired Starline 44 Mag brass available to measure, some was fired in a Rossi '92, some in hipguns.

- the diameter at the at the web is 0.452 - 0.453"
- the diameter at the pressure ring is 0.455" - 0.456", and the pressure ring does tend to expand offset because the extractor puts a bit of pressure on the case and force it into the chamber wall.

SAAMI spec for chamber max is 0.4629" and brass min is 0.4519", not exactly friction fit. Chamber min is 0.4589"

If you look at what my brass measures at when fired, and add the about 0.002" normal spring back, I'd say the chamber is about min. I measured the same ammo fired in my revolvers and they come out at about 0.4585, which would indicate a chamber between min and max.

44 Mag standard specs suck, CIP uses a spec for both rifles and handguns near to SAAMI handgun spec and both of those are different than the SAAMI Rifle spec for 44 mag. Your Chiappa should be built to CIP specs, and from what I can tell my Rossi is made to near CIP specs.

Any 44 Mag rifle built to SAAMI rifle specs will shoot very poorly as a rule, it will be fussy on ammo. Very rarely will your hipgun ammo shoot well in your rifle. My son's Rossi rifle will shoot just about anything well, so I decided to get another 44 for myself, a Marlin 1894. I tested it, and it was a disappointment. It is built to Marlin specs.

PM me if you have any specific questions.

Nitro
 
Hi All,

I have a full-stock Chiappa Mare's Leg -- or really a 12" barrelled 1892 in 44 Mag. I bought it for the challenge of a short barrel (it will do 3 moa). If an actual Winchester had been available, I would have bought one instead.

I've discovered a troubling issue. I'm reloading sub-sonic 240gr target loads with W231 and Ttegroup (I had it on hand). The fired (new) Starline brass has a slight bulge about .335" from the case head on one side only. Always the same side (basically up.... I can tell by the ejector mark on the primer). So I looked into it more. The fired brass (and the first box of aluminum Blazer) measures about .012" out of round at the case mouth consistently (the entire length of the case is similar).

As for the bulge, the warmest loads are worse, but we're talking only 8 grs of W231 for 1090 fps. At the bulge, it measures .020" out of round (I realize that technically, the actual "out of round" is half that, but I hope you get what I mean). The actual bulge is only about .002" or .003".

My questions:

Is this anything like normal?

Should I care? (Especially since I'm reloading -- I worry about premature head seperation). If I weren't reloading, I wouldn't care.

If it is a problem, how crazy am I to consider a re-barrell? (?? $ ??).

I've had it for four years, but only recently started shooting it. Forgot warrantee. I can't even find proof of purchase.

Thanks for reading.

Factory pmc does this is my marlin 1894 and western 6. I get a slight bulge when going over 10gr of unique, too.
 
I'd need a bit more data to add much to the discussion.

But consider:

44 mag brass is pretty tough, it takes a pretty stout load to expand the brass to seal the chamber.

I just happen to have some fired Starline 44 Mag brass available to measure, some was fired in a Rossi '92, some in hipguns.

- the diameter at the at the web is 0.452 - 0.453"
- the diameter at the pressure ring is 0.455" - 0.456", and the pressure ring does tend to expand offset because the extractor puts a bit of pressure on the case and force it into the chamber wall.

SAAMI spec for chamber max is 0.4629" and brass min is 0.4519", not exactly friction fit. Chamber min is 0.4589"

If you look at what my brass measures at when fired, and add the about 0.002" normal spring back, I'd say the chamber is about min. I measured the same ammo fired in my revolvers and they come out at about 0.4585, which would indicate a chamber between min and max.

44 Mag standard specs suck, CIP uses a spec for both rifles and handguns near to SAAMI handgun spec and both of those are different than the SAAMI Rifle spec for 44 mag. Your Chiappa should be built to CIP specs, and from what I can tell my Rossi is made to near CIP specs.

Any 44 Mag rifle built to SAAMI rifle specs will shoot very poorly as a rule, it will be fussy on ammo. Very rarely will your hipgun ammo shoot well in your rifle. My son's Rossi rifle will shoot just about anything well, so I decided to get another 44 for myself, a Marlin 1894. I tested it, and it was a disappointment. It is built to Marlin specs.

PM me if you have any specific questions.

Nitro

This is excellent information; thanks.

At the fire-formed case mouth I have .4510 by .4610. This seems very out of round to me.

At the bulge area, I have .4580 by .4600 on some warmer cases. I'm not sure where the pressure ring is exactly (I'm looking this up).
 
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I'm no expert, but... thos primers look strange to me. Not flattened, but cratered? I mean it almost looks like primer drag, but that only happens on a semi. Maybe headspace problem? Then again I could be completely wrong lol. My 44's don't do that and I go up to 24.5 of h110

I wonder if your locking lugs are engaging like they should.
 
What do factory load primers look like? Because those do look like they saw some serious pressure.

Are they cci magnum primers? Thats what i run and even with 20gr of h110 and 300gr bullets they are still flat and un cratered. (Safety note that might be slightly hot so work up to it if you want to try.)

But with a faster powder like unique i wont go above 10gr with a 220gr projectile. Seems like the pressure curve isnt good for what you want to do.
 
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There's a factory Blazer aluminum in that pic. The Blazer is way, way hotter than any of my reloads. I have chronographed every single hand-load -- and 1100 fps is the fastest. No bullet has been seated too deep or moved under recoil. All powder carefully measured on an RCBS 1010 scale one at a time.

Primers are Federal 150 -- non-magnum. My 875 fps puffer primers look the same as the Blazer to me.

The primers look funny because of the mark made by the ejector -- which is sort of part of the bolt face. Perhaps the ejector is a tad shorter than the actual bolt face. I doubt it is a problem. Look at the primers and delete the ejector mark from the equation (unless I'm incorrect -- which is possible)...

YnfE824.jpg
 
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Factory mangled? Did you buy it new or used-but-good ?

New. Chiappa factory mangled. Their screws are soft -- and torque specs must be adhered to. For what it's worth, the parts are all hard and very nicely made... although it was covered in razor-sharp edges. The loading gate would take the end of your finger off. These guns are projects -- or at least this one was. It has a very nice trigger.

I'll check the barrel in the chamber area for a bulge with a radius gauge... I forgot to bring the set home.
 
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My hot loads measure around 460".

I think if factory loads are appearing similar you should be ok but i would use a different powder and see.
 
Your Chiappa has the same bolt face style as my Rossi, and you do get a funky looking primer.

YCyw2lo.jpg


My reloads use a Rem 2 1/2 primer, which if you look at "the books" that seems to be the primer most often used with the 44 Mag. If I were to compare, you seem to have a bit more pressure than I do.

I've fooled with the 44 Mag, working up hunting loads and Cowboy loads. If you test with a chronograph it becomes evident that the faster burning powders aren't ideal. The one exception is Trail Boss. As you approach Hodgdons max loads, the ammo is pretty consistent. If you are after stouter loads, 2400 seems to be OK. If you reduce 2400 too much, ignition becomes erratic, and a magnum primer may be required. If I want a hunting load with jacketed bullets I use 296.

vAJVqrk.jpg


My load is decent enough, I'd like better #'s but it's good enough for government work. As you can see from the velocity is is not a max load, but I'd class it as stout, 1150 fps in a 4 5/8" hipgun is way past Cowboy, and 1550 in a rifle is past Cowboy as well. Back in the day, the starting load for the 44-40 with this bullet and 2400 powder was 1550 fps.

When you dabble in the pistol/rifle calibers you can expect anomalies. First off straight walled cases tend to do what they do, expand to seal the chamber, but not entirely fireform in the true sense of the word. They are not comparable bench rest or deer hunting calibers.

I've been accused of "overthinking" these (straight walled pistol calibers), but I like to have good ammo. You may very well have issues with your gun, but in fact you are just looking at the symptoms. Visually examining the cases, measuring, researching, all good. However, to measure the chamber would require making a cast of the chamber (Cerrosafe) and measuring the casting, or use the radius gauge you mentioned. (I'm not familiar with that tool, sounds neat.)

I'd suggest that you do that IF you were experiencing difficulties with sizing, accuracy, extraction, splitting cases or ????

I shoot Cowboy, and as such the goal for ammo is more like mouse sneeze pressures and low velocity. That can be a challenge, but it does give you an education. A straight walled case like the 44 Mag is not the same as a 44-40 with it's tapered case and thin brass. To get a cast bullet to shoot well at less than Kieth levels can be a challenge. Conventional wisdom would point you in the direction of a few grains of fast burning powder and you're good to to go. That kind of ammo will go bang, but it also goes poof sometimes. Powder forward against the bullets does silly things, powder against the primer works better in most instances. A large capacity case is a curse. I load my 357 Magnum ammo in 38 Long Colt cases. Loading in a shorter case is not an option with a '92. If your ammo is too long or too short, you will jam it up. 1.6" is ideal, the '92 was designed for the 44-40, and it was loaded @ 1.590", that OAL did not vary, all ammo was that length. The SAAMI spec for OAL is 1.540" - 1.592" for the 44-40.

Adhering to that same OAL can make 44 Magnum handgun and rifle data somewhat different, especially for cast bullets.

Nitro
 
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Here’s an angle to chew on oversized picture to see it all, you have a chamber it is whatever it is you have I fired resized brass that your shooting very light loads, maybe not enough to evenly. Expand the entire case to the chamber? Thus you notice irreregularity? It’s only popping out maybe where it’s softest or weakest rather than complete expansion? Fire a factory load and compare the two case before and after? See size difference I don’t know maybe a stretch but might be happening?
 
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