Rossi 92 chamber issue

[Gregor]

A friend just bought a Rossi 92 .357 Magnum 16" BBL. I noticed that the chamber appears to have been "throated" similar to a 1911, it looks egg shaped. It does feed .38 Special 158gr. LSWC flawlessly. Has Rossi modified the chamber on newer 92's, or has someone else worked on it?

[Griff]

I think I need a picture to understand what you're asking. Are you saying they've changed the leade from the chamber to the rifling... making it able to accept longer bullets before engaging the rifling; or are you saying they've "ramped" the bottom of the chamber to allow a longer round to feed easier?

[AJMD429]

Was it new or used...?

[Model 52B]

Throated similar to a 1911, would imply it's been "ramped".
How much is too much is a matter of degree. Here are three examples of factory ramped .45 Colts.

Here is the chamber on an Armi Sport Model 92 takedown:



Here's the throat on a Rossi 92:


And here's the throat on a Winchester Model 94:



The Rossi is middle of the road, while Model 94's chamber is pretty aggressively ramped. The Winchester however handles Ruger only loads just fine with no bulging of the brass. That's pretty much the weather gauge of when it's too much. carefully examine the brass to ensure there is no bulge corresponding to the ramped portion of the chamber. In the extreme, with overly soft brass, excessive pressure and an excessively ramped chamber you can get this:

[Pete44ru]

A friend just bought a Rossi 92 .357 Magnum 16" BBL. I noticed that the chamber appears to have been "throated" similar to a 1911, it looks egg shaped. It does feed .38 Special 158gr. LSWC flawlessly. Has Rossi modified the chamber on newer 92's, or has someone else worked on it?

AFAIK, Rossi isn't throating M92 chambers - so I would presume the throating on your friend's rifle to be done aftermarket.



.

[Gregor]

Thank's for the pictures and responses. I spent the other day at the gun club shooting it with .38 Spec. 158gr. LSWC and factory .357 Magnum loads. The beveling/throating/chamfering of the chamber is causing bulging of the case in the web area. The chamber is more egg shaped, off set to the 5 o'clock position and extends farther into the chamber than Model 52B's photos show.

My current digital camera cannot focus well enough to take a good picture. Myles, the rifles' owner, just bought it from a local gunstore, I am not sure if it was new or "as new" used. It looks new with no handling marks. He wanted me to work on his '92 as I had worked on mine, but after I saw the chamber, I told him I would shoot it first before any further work was considered.

I'll get a hold of Myles and see what he wants to do. (He is out of town on business).

I appreciate everyone's help.

[Model 52B]

Thank's for the pictures and responses. I spent the other day at the gun club shooting it with .38 Spec. 158gr. LSWC and factory .357 Magnum loads. The beveling/throating/chamfering of the chamber is causing bulging of the case in the web area. The chamber is more egg shaped, off set to the 5 o'clock position and extends farther into the chamber than Model 52B's photos show.

My current digital camera cannot focus well enough to take a good picture. Myles, the rifles' owner, just bought it from a local gunstore, I am not sure if it was new or "as new" used. It looks new with no handling marks. He wanted me to work on his '92 as I had worked on mine, but after I saw the chamber, I told him I would shoot it first before any further work was considered.

I'll get a hold of Myles and see what he wants to do. (He is out of town on business).

I appreciate everyone's help.

One of the major attributes of the Model 92 is that it is a very strong action (it handles .454 Casull just fine at the SAAMI spec of 65,000 psi) and it would be unfortunate for a poorly throated chamber to compromise that strength.

I will normally see a very slight asymmetrical bulge on .45 Colt cases fired in my Winchester - very subtle but there - that is not evident on the same loads fired in a Blackhawk, and it's never been an issue. But if that .357 is bulging cases to any significant degree, I'd return it.

[Gregor]

Thanks Model52B for the information. Myles told me he bought it from a LGS and that the rifle came from a collector that did not shoot it, supposedly. He called Rossi and was told that their firearms carry a one year warranty from date of manufacture, based on serial number. He was quoted $225 for the barrel, $30 bench fee and $50 shipping. He's decided to keep it and told me to tune it up.

The cases resize to remove the bulge, but I am not sure if the brass is over stretched to the point of future failure. He doesn't reload and told me he would live with it.

[Tycer]

You could have the barrel shoulder turned a few thousands and recut the chamber and extractor groove.