Results of My Pedersoli 1874 Sharps 45-70

[JKR]

In your opening post you mentioned having shot some smokeless loads with jacketed bullets. Is is possible that it might be these cases? I ask because I’ve not needed to resize any of my BP cases.
Do you have another 45-70? I have two and cases don’t interchange.
I guess I’d resize them so they fit and carry on. No doubt you’ll get other opinions.
JKR

[Don McDowell]

Resize this batch of cases
If the chamber fine then load and fire them again with your Blackpowder loads
Like JKR said the higher pressure of the smokeless may very well expand them enough to make resizing mandatory
If they won’t chamber without resizing then you have a chamber problem that likely can only be fixed by either tebarreling or lining and rechambering

[Gunlaker]

There are a couple of things that can make fireformed cases not chamber properly. First is a chamber that's oval instead of round. See if the brass will chamber if you rotate the case to a different orientation. I've never experienced this, but I have heard of it.

The second one is something that I have experienced. My first C. Sharps 1885 had a really poorly cut chamber. Way too fat at the base. The brass would eventually expand to the point that it would hang up on the extractor. An old gun smith I knew suggested taking the extractor out and seeing if the brass would then chamber. The "fix" was to rebarrel or carefully reprofile the edge of the extractor so that it didn't hit the case body. That's what I did. I eventually sold that rifle.

Chris.

[RSAPD]

Thanks everyone. I'll test all those suggestions. It has not been happening, so I am little perplexed it started. Chris, I think your extractor issue has some merit. Any case FL sized slips in easy and extractor has no problem. Once the cases have been fired, it does seem the extract or can hang up. I'll look at that more closely.

[indian joe]

Thanks everyone. I'll test all those suggestions. It has not been happening, so I am little perplexed it started. Chris, I think your extractor issue has some merit. Any case FL sized slips in easy and extractor has no problem. Once the cases have been fired, it does seem the extract or can hang up. I'll look at that more closely.

are you orienting the brass to the chamber? most of the fellers I see are doing that - file a notch in the rim before first firing and that always goes TDC (up) - if thers any more than a hair of neck clearance the case will lie at the bottom of the chamber and expansion is one sided and that makes for uneven next time it goes in.

most resize dies take dimensions back too small for most chambers (thats hard on brass) usually when chambering gets sticky its that bump just ahead of the solid head causing the jam. I made a body die that just gives that bump a tiny squeeze without sizing the remainder of the case body - time will tell but it seems like that bit of a touch last almost as long as a full resize. Tight brass will usually spring back a touch from the chamber walls and extract easier than it went in (test this theory with a bolt gun with its extra camming power). So alls you need is for it to JUST chamber without being sticky.

If you making any kind of swage die they must be polished like glass inside so they dont scratch the cases.

[RSAPD]

are you orienting the brass to the chamber? most of the fellers I see are doing that - file a notch in the rim before first firing and that always goes TDC (up) - if thers any more than a hair of neck clearance the case will lie at the bottom of the chamber and expansion is one sided and that makes for uneven next time it goes in.

most resize dies take dimensions back too small for most chambers (thats hard on brass) usually when chambering gets sticky its that bump just ahead of the solid head causing the jam. I made a body die that just gives that bump a tiny squeeze without sizing the remainder of the case body - time will tell but it seems like that bit of a touch last almost as long as a full resize. Tight brass will usually spring back a touch from the chamber walls and extract easier than it went in (test this theory with a bolt gun with its extra camming power). So alls you need is for it to JUST chamber without being sticky.

If you making any kind of swage die they must be polished like glass inside so they dont scratch the cases.

OK, sounds similar to what Chris was saying. Interesting, I'll keep track of that. Thanks.