Case bulge 45-70
12-05-2006, 08:42 AM
#11
Giant Nontypical
Join Date: Feb 2003
Location: Texas - BUT NOW in Madison County, NY
Posts: 6,270
RE: Case bulge 45-70
ORIGINAL: bigcountry
Out of my Marlin 1895 lever (post 72) with microgroove, I have been shooting IMR4198 with 300gr partition.
At 46-47gr, I get a slight bulge above the rim. With new brass (winchester) as a comparison, I get a .0054" bulge using starrett mic's. Woudl that be of concern to those who understand and look for this expansion? It is noticable. Primers look great. I am getting around 2050fps.
I need to go thru my old remington brass to see if I see the same. I did all my original load development with remington brass from 41gr-51gr. Nothing stuck out in my mind as an issue. I was told by Brian Pearce from handloader and rifle mag, that this action (1980's) can easily digest this load up to 51gr. Nosler also told me the same. But lymans and Sierra back off majorly for any leverl, post 72 or not.
I get 1.5MOA accuracy at 100 yards with 46gr, but it starts stringing vertically past that.
Out of my Marlin 1895 lever (post 72) with microgroove, I have been shooting IMR4198 with 300gr partition.
At 46-47gr, I get a slight bulge above the rim. With new brass (winchester) as a comparison, I get a .0054" bulge using starrett mic's. Woudl that be of concern to those who understand and look for this expansion? It is noticable. Primers look great. I am getting around 2050fps.
I need to go thru my old remington brass to see if I see the same. I did all my original load development with remington brass from 41gr-51gr. Nothing stuck out in my mind as an issue. I was told by Brian Pearce from handloader and rifle mag, that this action (1980's) can easily digest this load up to 51gr. Nosler also told me the same. But lymans and Sierra back off majorly for any leverl, post 72 or not.
I get 1.5MOA accuracy at 100 yards with 46gr, but it starts stringing vertically past that.
If you do size the bulges out each time, it will overwork the brass, and the caseswill eventually crack in that spot. Adjust your sizing die to reduce the fired cases so they will re-enter the chamber relatively easily and give a firm grip on the bullet, and no more than that!
If you are getting acceptable accuracy at 46 graiins and things go down the tubes after 46 grains, stop at 46 grains! I have found that, in the Ruger No. 1 at least (and in an opld M1886 Win. I used to have) that IMR 3031 and Alliant RE 7 are my two best powders for the .45/70. BUT, I shooot 350 and 400-grain bullets only. Tried 300 grain bullets. They didn't shoot well for me no matter what powder charge was used.....
12-10-2006, 02:19 PM
#13
Giant Nontypical
Join Date: Feb 2003
Location: Texas - BUT NOW in Madison County, NY
Posts: 6,270
RE: Case bulge 45-70
ORIGINAL: bigcountry
Eld, the 45-70 is a tapered round, correct? So I almost have to size all the way down to get get good bullet grip? I will try it out.
Eld, the 45-70 is a tapered round, correct? So I almost have to size all the way down to get get good bullet grip? I will try it out.
12-17-2006, 11:46 AM
#14
Nontypical Buck
Join Date: Nov 2006
Location: NW Florida
Posts: 1,838
RE: Case bulge 45-70
I was getting some case bulge on my 45LC and an old feller at the gun shop told me that as long as it still chambers and don't bind, live with it. Much like our Texan friend above stated
12-19-2006, 08:28 AM
#16
Nontypical Buck
Join Date: Aug 2006
Location: Rivesville, WV
Posts: 3,192
RE: Case bulge 45-70
Most lever gunners will recommend that you full length size brass that is going to be used in a lever. I neck size 45-70's in my single shots, but I also align the cases. It is difficult to align case in a lever. I recommend you FL size, not neck size, or partially size. If you can back off a little and stop the bulge, that leads me to believe it is excessive pressure. That pressure could be caused by your crimp. Are you roll crimping, or taper crimping? At over 2000 fps I do not want to shoot that load.
I am not a gunsmith-nor an expert. But I do have a question.I thought that fireforming a case would expand the case to the size of the chamber? Are you guys saying that it takes excessive pressure to expand your brass to an oversized chamber? I could be wrong, but that does not make any sense to me. Especially when we are talking .005. I would assume any load would expand the brass to theoversized chamber.
I suggest you go to the "Levergun" web site. There are alot of Marlin experts over there. If you do not want to join just let me know. I will post your question for you. Tom.
I am not a gunsmith-nor an expert. But I do have a question.I thought that fireforming a case would expand the case to the size of the chamber? Are you guys saying that it takes excessive pressure to expand your brass to an oversized chamber? I could be wrong, but that does not make any sense to me. Especially when we are talking .005. I would assume any load would expand the brass to theoversized chamber.
I suggest you go to the "Levergun" web site. There are alot of Marlin experts over there. If you do not want to join just let me know. I will post your question for you. Tom.
