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jj500
07-20-2017, 05:35 PM
I have a Italian 45-70 Sharps and was measuring the chamber length and found it longer than a normal 45-70 OAL. Supposedly the OAl for a 45-70 is 2.55 but in measuring mine it comes out to be 2.80.Thats measuring from the breech block closed to the muzzle,then putting a bullet only until it touches the rifling and then measuring that with a measurement of 2.80.Should I be leaving the bullets out more,now I am seating them to the front lube ring but that still leaves a lot of space.Will that difference affect accuracy? I am currently using 70 grains Black,fiber wad and a 500 grain bullet.Maybe a 535 bullet? Any suggestions.

Gunlaker
07-20-2017, 05:57 PM
Do not worry about published OAL. Those are mostly for smokeless levergun shooters. A very good place to start with black powder is to have the most forward driving band lightly engraved by the rifling. In a Sharps you don't want it so long that you have to put considerable force on the lever to close the block though.

Chris.

NSB
07-20-2017, 06:28 PM
The bullet ogive will give different readings the way you're doing it. A lighter bullet will seat deeper than a heavier one. Most of the Italian guns have a more generous chamber than the Winchester/Miroku guns. I've owned several Miroku guns that shoot fantastic but needed the throat lengthened to get best results with heavier bullets....which also shot better than the lighter ones.

longrange2
07-20-2017, 07:19 PM
Chamber cast would help, I use piece of dowel plus milk carton wads start with first driving band at mouth of case and add wads till contact with rifling then measure. Vic.

Edward
07-20-2017, 09:20 PM
I"ll start by saying I am a complete 68yr old newbee but am having fun with a new to me C Sharps 45/70 ,34 " Badger barrel 1/18 twist Long range venier/front Globe .Today I shot @ 400 and for the 1st time 700yds .At the end of the day (good one) I managed to ruin our 5ft saw blade ,some holes were 4+inches .The boolit was a paper patched 443/526 grain Eliptical from BACO . New starline brass /CCI primers/76 grains OE 2F/1 60thou poly wad /and a newspaper wad under the 9 Lb 2 wraps onionskin compressed powder 150 and the finished boolit isn't close to overall length ,measures 3.400 as shown . I can fit 82grains and it still loads with thumb pressure and gets more attention than the neighbors bolt guns !/ 200075200076

jj500
07-20-2017, 10:59 PM
In messing around with how far the boolit is seated ,I can get the length I need.I seated the boolit with the top lube ring just out of the case and this gives me about 2.75 and it goes into the chamber without any pressure on it.This puts the boolit within .005 of the rifling without touching it.With this seated like this will it give me any problems or do all the lube grooves need to be in the case?

longrange2
07-21-2017, 12:00 AM
Hi jj500, That will be fine be mindfull of fowling in start of chamber if shooting dirty as it can cause chambering problems on consective rounds without cleaning. Vic.

jj500
07-21-2017, 12:21 AM
Good advice Vic,I will keep an eye on it,just trying now to get some wisdom on this,its all fairly new to me. I have shot muzzle loaders for quite a while now but this is new.