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charger 1
08-12-2007, 05:56 AM
I know that a fella should/must fill the chamber with brass. Lets just say that is entirely impossible. So if we took the example of firing say 45/70 brass in a 45/100 or 110. Something chambered .6 - .8 longer than the brass he had out of all the methods to make the jump which I will establish again are poor, which of the poor would be best. My thing says a hard bullet, maybe hardened to 30 or so fired with small amounts of a quick burner behing a he11 of a crimp to get it to jump
THOUGHT?

Bret4207
08-12-2007, 07:26 AM
If I'm reading this right you want to get the boolit to the throat without obturating or otherwise going haywire. I'd say a harder booilt would work, but you could make it heat treated and try that before going to 30 Bhn alloy. I would also consider using a slower powder with a long pressure curve to avoid bumping. Depending on you throat style and leade angle you might be able to use a nice fat boolit and fill the neck area and get good results that way.

Nueces
08-12-2007, 09:39 AM
If you want the slug not to obturate before reaching the throat, are you not inviting gas cutting? My own thinking on this has lead me to consider use of the 'soft gas check' wax sheets to make a cookie at the base of the boolit. Reducing gas cutting in situations like this is it's design function. If you'd like to try it, PM me your address and I'll send you a sheet.

Mark

charger 1
08-12-2007, 09:56 AM
If you want the slug not to obturate before reaching the throat, are you not inviting gas cutting? My own thinking on this has lead me to consider use of the 'soft gas check' wax sheets to make a cookie at the base of the boolit. Reducing gas cutting in situations like this is it's design function. If you'd like to try it, PM me your address and I'll send you a sheet.

Mark

Theres some out being heat treated as we talk. I tend to use quite the stack of PSB behind 3031 to slow the cutting. I guess we'll see in a week or so

Bret4207
08-12-2007, 10:02 AM
If you want the slug not to obturate before reaching the throat, are you not inviting gas cutting? My own thinking on this has lead me to consider use of the 'soft gas check' wax sheets to make a cookie at the base of the boolit. Reducing gas cutting in situations like this is it's design function. If you'd like to try it, PM me your address and I'll send you a sheet.

Mark

Depends on how long the jump and the boolit length/diameter. If it fill the case neck and the neck is tight the gas shouldn't be forcing itself by until the base exits the neck. If the boolit is into the leade by then it should obturate about then depending on the pressure curve. Bassackwards, Larry Gibson and Felix could explain it better.

Larry Gibson
08-12-2007, 11:31 AM
Charger 1

Worked with a fellow that spent all his money on the 110 Shiloh Sharps and hadn't the forsight to order proper cases during the 2 year wait. Anyways, in the interim he tried bullets of 1-30/1-20 alloy in 45-70 cases with smokeless loads of Unique and 4198. The fellow is a pretty good shot so when the best he got was 5-6" groups at 100 yards he was some what crestfallen. He came to me for help and we loaded some Lee 405 HP bullets as cast at .464" of WQWWs and hand lubed with Javelina. I chose this bullet because of the long bearing surface and oversize as cast diameter. We also spent a little time getting the leading out of the throat area from his previous shooting. I loaded the cases with a known accurate charge of 4895, put a 1 1/2 gr dacron filler in, a .006" veggie wad over that and then seated the bullet so the front driving band was slightly engraved by the rifling. He only had 20 cases so with those thus loaded we headed to the range. His first 5 shot group was just over 3" as I recall and it was hard to get him settled down to shoot well again after dancing the jigg up and down the firing line! Now 3" groups isn't that great for a rifle of that quality but given the circumstance he was pretty tickled. I suggested that we could tweak the load for maybe better accuracy but he was happy as was. We loaded those 20 cases several times over in the next couple weeks then his 110 cases came in. I had some concern that the chamber mouth might scrape off a lead ring but it didn't happen. He's gone totally to the dark side (BP) with that rifle but that is as it should be. He's some loads with the Lyman schmitzer bullet that are running 2-3" for 5 shots at 200 yards so he's a real happy camper now.

Anyways that's what I did for using 45-70 cases in a 110 chamber. One other thing; the cases were very slightly sized with a FL die so my .459 expander just touched the case walls for about 1/2" depth. This gave sufficient neck tension on the bullets.

Larry Gibson