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jacob7
10-12-2011, 10:24 PM
This question is pretty pacific to Pederosli 45-70 sharps owners, what brass case lengths are you getting good results with. I'm thinking of getting 45-90 cases and cutting them down to some size but don't know where to start. Thanks

Dan Cash
10-12-2011, 10:51 PM
The Pedersoli for which I load requires a 2.05 case to reach the front end of the chamber. Shorter brass leads. I have tried stretching the brass but it will not reliabley stretch that much (Starline @1.875). The gun belongs to a friend and he is pondering buying and trimming .45-90 cases or having the barrel set back one or two threads and properly rechambered. The rechambering job looks like it is more cost effective.

ss40_70
10-12-2011, 11:01 PM
a good place to start is to do a chamber cast if your having problems , if your not getting leading with greasers or paper rings , patching spending the extra cash on 2.4 cases might not give you any better results

shovel80
10-13-2011, 12:09 AM
Dan Cash...2.05 is already a shorter chamber than what is correct for a 45-70.....which is 2.100...I believe...
I have a Taylor Arms 45-70 with a chamber almost 2.200...and if I seat the bullets out with one grease groove exposed, I don't get any leading!...I'd rather have the correct chamber though...and have also thought about going too the 2.4/ .45-90 Brass , and shorten it.
I haven't decided if It would make a difference in accuracy yet or not...

Terry

bigted
10-13-2011, 07:36 AM
interesting post. i also would like an answer but im bettin that like all here...im just gonna get some 45-90 brass and do my own experiment.

i recently came to a startling discovery myself... the brass that i been using and trimming with my lee trimmer is WAY did i not say this loud enough...WAY!!! short...mesuring 1.850 in length after trimming with this lil devil. sad part is that tucked back under other stuff is a motor driven trimmer that i should have been using all this time. i have some new rp brass as well as ww cases so will have to start all over with my experiments with accuracy and case length. they measure 1.095 being new and UN-sized...ill try to chamber these without sizing initially and if possible i wont do anything but prime n shoot with bp so as to get the most explosive action inside them initially for chamber forming and final lengthening if they will.

as they say tho.......live n learn!!! guess im not there yet....DANG !!!

John Boy
10-13-2011, 07:54 AM
Here is the Pedersoli factory nominal blueprint specifications for the chamber of their 45-70 with reamer control depth of +.003" and -.000" tolerances :
Rim Dia. .618"
Rim width .070 (depth of rim seat)
Case dia at rim base .508
Case length 2.129 (includes .070 rim thickness)
Length of 45 deg angle .060
Diameter at rear of throat (at 45 deg angle) .4598
Length of throat .236
Diameter of throat at front .4578
Leade angle 1 deg. 30 min

and ...
Bore dia, .4500"
Groove dia .4580"

Garys007
10-13-2011, 09:14 AM
My Starline 45-70 brass lengths were from 2.085" to 2.091" (purchased a lot of 250 pieces). I trimmed them all to 2.085". This length includes the rim.

All of my fired casings have a ring of lube approximately .050" wide at the mouth of the casing. I haven't done a camber casting, but adding my case length with the ring I get 2.135". That's very close to the numbers above in John's post. My rifle is a Pedersoli.

I've had the rifle for 7 months now and haven't changed the casing length at all. I have one grease groove exposed and have not gotten any leading at all, so I figure why worry about the case length?

Just as an fyi... I currently use CCI large rifle primers, 67.0 grains of Goes 2f, .030 thick veggi wad and Montana Precision 525 grain Saeco 745 bullets seated against the rifling. I just purchased casting equipment and am gong to start casting Lyman Postall bullets (#457132) using 20:1 lead.

Gary

montana_charlie
10-13-2011, 11:59 AM
I have tried stretching the brass but it will not reliabley stretch that much (Starline @1.875).
The brass WILL stretch that much, but it can't be done reliably by firing it.
This will do the job ...
http://kal.castpics.net/CaseStretcher.html

... and this is how it does it ...
http://www.youtube.com/watch?v=oGzQsrPT4Qs

CM

gunplumber
10-13-2011, 10:25 PM
i loaded and shot 200 new RP brass and after firing they pretty consistantly measured 2.090 to 2.095, i streached all the brass to 2.110 and trimmed back to 2.108 to square the mouths. after loading and shooting again they are averaging 2.104 to 2.105. i think when fired after sizing you can plan on the cases being shorter after firing. the only time ive had a 45/70 case get longer when fired with BP was in a wet chamber. Ive never found a new brass that i thought was as long as it should of been when new. just loaded 50 new winchester brass for a different rifle and will measure them after firing and see how much they shorten when fired