1873 extraction resistance issue.
First look at the file marked Ammo in a rifle. If this is not the issue you may have a defective chamber or another problem.
If this is a rifle with the new style bolt it may be related to poor workmanship at the factory in Italy.
First let's talk about small caliber bolt history in a Uberti 1873 rifle.
Years ago Uberti made a very good bolt that was held together with a small pin. They redesigned the bolt so the extension was held in by a wedge shaped keeper and the bolt was still a very good bolt that lasted for years and years of cowboy action. Then something changed, people speculate they changed the steel or manufacturer and the lower tab started breaking. At first for a year or so Uberti either didn't know or didn't realize they had a problem and continued making the same bolt. Then about the W4XXXX serial number they made a modification. The tab was beefed up to resemble I'll call a mini large caliber tab design. This had a design flaw by having a sharp corner at the face of the bolt and started to fail. This ended about the late W5XXXX or very early W6XXXX when they introduced the removable tab. This has so far proven to be a good design.
Now to get to our problem / solution, first you need to understand the dynamics of what is happening. After a round is fired the force on the bolt (with a short stroke) has a tendency to pull it down as it moves rearward. When the only support is a narrow piece of material rearward of the carrier. The bottom of the bolt rides on this hole.
The bottom of the bolt needs to be round. The new design of the tab is flat on the bottom, so, it needs to be modified a LITTLE. The problem comes in at the factory when a worker on a belt sander removes material off the bottom of the bolt and not just the edges of the tab.
This allows the bolt to drop and drag the round out of the chamber with excess friction on the bottom. To increase the problem they usually remove more material in the center than the ends causing the bolt to rise fighting the links.
Solution: replace the tab, break the sharp corners improve the transition at the rear of the insert. The tab is not listed in the diagram it is in the parts list at the bottom. The pin is .060" a 1/16" punch .0625" ground down to .058" works.
When I get a chance I'll post this on www.wheelergunworks.com under helpful hints.