School me please..

[Camel73]

Bullet pinch.
I thought I read somewhere a while back about this being an issue. I've tried searching and couldn't find much at all.

Any guidance would be appreciated, as I'm all set to go for mess'n with my 94.

[Nath]

Bullet pinch, is that what you get when carrying loose rounds in your pants pocket?
Try Vaseline.
N.

[GunnyMack]

Or talcum powder

What exactly does bullet pinch mean to you?
Neck tension.
Obturation in the bore?

Please try to describe this to us, we may know it as a different term...

[Blaine]

Pinche?

[Chuck 100 yd]

Bullet pinch refers to the need for a small amount of clearance between the loaded rounds neck and the neck area inside the chamber. A little clearance is required to allow the case neck to expand and release the bullet when fired. If the loaded round allows no room for the case to expand pressures can spike into dangerous territory.
Measure a fired cases neck and measure a loaded rounds neck. The loaded rounds neck should be at least a couple thousandths smaller in diameter than a fired case. Benchrest shooters sometimes use cases with such tight fit that the cases need no resizing at all to hold a bullet. Not a good idea in a hunting rifle.

[AJMD429]

Then I'm guessing both my Marlin and Rossi 44 Mag and 45 Colt rifles don't have 'bullet pinch'.....the darned cases expand to about 50 caliber after firing in those chambers (a slight exaggeration, perhaps)...

No such problem with different makes of 357 Mag, 218 Bee, 32-20, 30-30, 35 Rem, 375 Win, 444 Marlin, 454 Casull, or 45-70 though, so I'm guessing it is more related to those two chamberings, rather than gun brand.

[Griff]

Then I'm guessing both my Marlin and Rossi 44 Mag and 45 Colt rifles don't have 'bullet pinch'.....the darned cases expand to about 50 caliber after firing in those chambers (a slight exaggeration, perhaps)...

I don't currently own a 44Mag rifle, so... at least for the 45 Colt, rifle makers seem to use a reamer that cuts the chamber to near max SAAMI specs... in a (I'm guessing), perceived notion that to chamber these big, fat rounds, in a wide variety of bullet shapes the chamber has to be "big" to allow proper feeding the chambering. The only one of my 45 Colt rifles that isn't cut on the large side, is my Browning 1885.

[Pisgah]

Leverguns have limitations on how long a cartridge can be loaded and still work through the action. Chances are, if you load a round long enough for bullet pinch to occur it won't feed from the magazine in to the action anyway.

[Chuck 100 yd]

The only time I experienced bullet pinch was when I sized some Win. .308 brass down to .243 without turning ( thinning)
The necks. Using my regular medium load in them I imediatly was getting extreame pressure signs. As I did not have neck turning
Tools at the time, I scrapped that brass and bought some new .243 brass and everything was back to normal.

[Camel73]

Thanks for replying everyone.. Chuck 100 yd nailed it.

I'm surprised I couldn't really find much, but this is what I was referring to. Thank you!

I'm just getting my feet wet with cast and I noticed the .50 cal deal as well, lol. I did a chamber cast and I found a few other interesting things. (My brass actually shrinks when firing factory sized brass, and my chamber can house a piece of brass 2.090" long!)

So for fun I ordered a full length size die with the neck punched out to .329" - chamber neck is .3315".

It came in the mail from Lee about a week ago but I've just been too busy. Tis the season!

[Chuck 100 yd]

Since you know the chamber neck diameter you will need to compare that to a loaded rounds diameter with the bullet that you will be shooting seated. You should have at least a couple thousands clearance to allow bullet release.
You can also cause bullet pinch by having cases that are longer than the chamber and jamming the case into the chambers lead will cause pinch. Also a bad deal.check your brass overall length.
Some early rifles have tight chambers compared to their groove diameter and bullets sized to properly fit the bore won't chamber
With standard thickness brass, case necks have to be turned/reamed to allow proper chambering in that case.. Just some of the things reloader run into.

[Camel73]

I think I've got it now. Thanks for the explanations.