Originally Posted by
wildeboer
I have a new rifle(to me) in my safe, got it as part of payment for a job I did.
It's a Mkontho in-line rifle based on the Pauley design(plunger), they are build in South Africa by a local gunsmith and proofed up to 150gr loads.
The rifle has a 1:24 twist, 21 1/2 inch barrel(measured from crown till touching breechplug), .451caliber and ignited with a standard no11 percussion cap. No open sights, fitted a old Bushnell 3-9x40 scope.
I have slugged the barrel, 0,457" and 0.452" measured. I have the Lee .457"mold that cast them at 405gr depending on the lead. I also have a .452" Lee re-sizer. I want accuracy and not so much speed as the rifle are supposedly very accurate at longer distances.
What do you guys suggest concerning diameter and possible starting loads? The gunsmith suggested 3F which I luckily had for my and a starting load around 85-90gr(volume).
you should be about .010 thou under sized of the barrel and really shouldn't size more that about .003 thou difference from size cast to final size you probably should get a new mold in that case. are you shooting round ball i should have asked that question first. 3f is ok but i would try both they say 3f for .45 cal and smaller but not always the better choice you just have to experiment with load combinations if your planning on target shooting 50-80 gr max if hunting 80-max load depending on game,possible distances and of course accuracy.