Trapdoor Collector Discussion Board
[ Read Responses | Post a New Response | Return to the Index ]
[ Previous | Previous in Thread | Next in Thread | Next ]
Posted by Larry Gibson on Tuesday, 5 August 2014, at 9:53 p.m., in response to Re: H4895, posted by Jerry Ipsen on Sunday, 3 August 2014, at 1:25 p.m.
"Thinking about not going over 40 grains."
That's a good max load for TDs considering MV and recoil. The 47 gr load Ernie mentions will let you know you pulled a trigger in the TD! Also you will see different psi's used for the 45-70. The 22,000 Ernie mentions is based on C.U.P. method of psi measurement based on actual black powder loads. Most current data reflects peizo-transducer/strain gauge measurements. The SAAMI MAP (Maximum Average Pressure) with smokeless powders in the 45-70 (for use in the TD) is 28,000 psi. The 40 gr 4895 load, even with the Dacron filler, will be well below that.
I pressure tested (M43 Oehler PBL) my own 4895 load of 37 gr surplus 4895 + the Dacron filler under a 413 gr hard cast bullet; 1391 fps (24" test barrel) at 22,400 psi(M43).
Post a New Response
Return to the Trapdoor Collector home page via this link.