Do I have a Brass or Chamber problem?

[Red Dot]

I am loading for a .223, 12", Contender, Custom Shop.
I am loading a starting charge of 20.5 gr. H4198 using 50 gr. Berger standard, just off the lands.
With cases fullsized, prepped, charged and bullets installed. Off to the range. Winchester Brass.

Today I shot 20 rounds, 4 five shot strings over 30 minutes.
Here is what I find: average groups w/ 2x20 Leupold
Fullsized measurement at base .374 Unfired
After firing the cases measured .375 to .377 (correction .3757).

Only three of the fired cases would close properly, when fitted in the chamber.
The rest went from hard to very hard to close.

It seems as though they grew bigger as the barrel heated up.

I have been full sizing because of this problem and I thought I would look into it.

Do I have a brass or chamber problem? Your thoughts please.
Thanks Jerry

[TreeDoc]

I'm no Guru on this but I would think your brass can only grow in diameter up to the size of the chamber and no more. Maybe you can take one of those fireformed cases and put it through the FL Die after screwing the die out a full turn then try it in the chamber.

[Rocky Raab]

That amount of case expansion should raise red flags. Start loads shouldn't result in ANY base expansion, so there's certainly something wrong going on here.

Is this new brass, once-fired or "tired"?

Standard primers or mags?

And a few gun questions: Is this a recent Contender frame, or an older one? You say it's a Custom House barrel, but is that the T/C Custom House or somewhere else, and is the barrel unaltered since then? (I'm wondering if it was originally a .22LR from the custom house, for example.)

[Red Dot]

Rocky,
I am using standard Winchester

This is a TC Custom Shop barrel I had made 10 years ago and haven't used until very recently. Has had about 200 rounds fired in it. ITS As NEW Ser # 445254.

I am going out right now and fire some reloads using Black Hills Match, with 22 gr. H 4198 and 40 gr. V Max.

Will post these results/ It may be the brass.

Jerry

[PJgunner]

Hmmmm! Is that .377" dimension on just one side of the casing? Maybe your chamber is a bit on the large side for the round. A case laying at the bottom of such a chamber would expand more on the unsupported side than the side that was at the bottom of the chamber.
What does bother me is, if that was a custom barrel with custom chamber, I find it unsettling that it would be oversized in it's dimensions.
The fact that you've had that barrel for such a long time probably means you can't get the factory to fix it for free. In fact, it would most likely take a whole new barrel with chamber at the proper dimensions to square that problem away.
Probably the only real problem might be a bit shorter brass life, but with .223 being so plentiful, that wouldn't be much of a problem.
Paul B.

[Catfish]

Jerry,
It`s hard when you can`t put your hands on the gun and brass but, it sounds like a presure problem. Your not seating your bullets into the lands are you??? I don`t think that the Custom shop would put out a .223 bore in a .223, but that would cause the problem. One other thing I can think of, is your barrel locking up tight? If you hinge pin is worn it might alow for some barrel movement. Are the cases showing any other signs of presure????? :confused:

[Red Dot]

Back from range. Made a correction on the origional post the measurement was .3757 not .377.

I fired 16 rounds the average fired diameter was .3745 which is normal.
All ejected normally, after firing and trying them 6 were hard to open and close. I could rotate the brass and finally get a spot where they would open and close properly. They were a little out of round, I full sized them and they opened and closed properly.
The extractor is tight and that may have a bearing on the out of round.

Jerry

[Red Dot]

Catfish,
I probably have .020 clearance at lands, no other signs of pressure.
Barrel locks up tight, and the hinge pin is tight.

The measurements on this last batch were normal so I can't explain the first measurements.
Jerry

[Rocky Raab]

Well, it does prove that micrometers are hard to use.

T/C has often been accused of producing off-center or out-of-round chambers. It sounds as though you have another log to add to that fire.

It's also an object lesson on why rimmed rounds are much better for break-open actions. For a rimless round, the T/C extractor is under spring pressure. That allows it to be pushed down so a round can be chambered, but then snap up into the extractor groove.

But that same upward pressure very often "cocks" the round in the chamber. It doesn't do much for accuracy, and (as we've seen here) it can also result in crooked, egg-shaped brass after firing. It's worse if the chamber itself is off-round or oversized.

If it were my barrel, I'd trade it off for a better one. Preferably one with a rim.

[earschplitinloudenboomer]

...might do a chamber cast and check for roundness...had a new Win. Ultralight in .222. Chamber was not round. Fire formed cases would not chamber. As long as I full length resized everything was o.k.
...just something you might want to check.

[Red Dot]

Thanks to everyone for your response.
The barrel shoots good so I will just fullsize and let it be, as I dont think I have a pressure problem. Thanks to you all!!
Jerry

[skb2706]

Without actually seeing it but based on what you have stated you have "no problem". New brass that expands .001"- .0017" to fit your chamber is not at all uncommon. Where are you measuring the brass at ? Often in break action guns it is necessary to bump the shoulder back to get proper headspace on once fired brass and it is also not uncommon for the brass to not chamber well after firing but prior to this process of bumping the shoulder back. I would not let it concern me much that fired brass does not chamber....it would serve no purpose if it did.

[Catfish]

Glad to hear your problem is a no problem. I`ve been playing with a .222 Rem. 14 in. barrel on a Contender lately and it going to cost me another $470. I was looking for a good 100 yrds. coyote gun to use from my hoe, so I put a 2X Leupold scope on it. BUT, when I put it on paper at 100 yrds. with a 4 in. circle for an aim point I put 4 bullets in .460 and with the 5 th, bullet the group was still under 2 ins. That barrel just have to have a 2 1/2 x 8 Vari Xlll EER scope on it. Now I`ve got a good 250 yrds. gun, don`t you hate it when things like that happen. :D

[Cal Sibley]

I'm having a somewhat similar chambering problem with a new .25-06. The cases necks are getting blown out in firing and using neck dies for resizing doesn't bump the shoulder back so the fired rounds will not rechamber. I've been using a Redding bump die to reposition the shoulder, then size the neck separately. When I read your post my impression was that might be your problem, blown out shoulders. Best wishes.

Cal - Montreal