POI with PC Boolits?

[ChristopherO]

In the 45/70 the cast Accurate 460 FNGC projectiles at 1,620 fps is a known entity. For the sake of interest I shot 4 of the same load but with PC instead of LAR's 2500+ in the grease grooves. This was at 100 yards with Skinner a aperture site off shooting sticks. Granted, this wasn't a bench rest session with the 1895 CB, more of hunting practice. From this small sample it appears that the 4 rounds grouped well enough for as late in the day these were shot, but may be a tad low from what I am used to with the the lubed boolits. What do you gents normally see when switching to powder coat?
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[ChristopherO]

Actually, reviewing that target that was not a good group at all. It doesn't compare to the ladder loads using IMR 4227 and PC. All shot at the same time the 4227 was much tighter. Yet, this was at the end of a long day of work (labor day is labor day) and the daylight was waning fast. Here's a picture of IMR 4227
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Yes, I use up the older cans of powder when I am talking about H2400 (Hercules) and IMR4227. Next will be the H4227 (Hodgdon).

[Smoke4320]

More than likely you will need to rework your load for pc as you will gain approx 4 to 5% in velocity which will change barrel harmonics

[ChristopherO]

Good to know. I purchased my PC from you a good while back. Think I will be working with it more as I become accustom to the new dynamics.

[Win94ae]

My 45-70 basically has a bull barrel, and see no difference in POI at 100 yards. I don't see a difference with jacketed bullets, at close to the same weight.
Of course, my entire ladder test group, was just a few inches, at about 2200fps.

[Kraschenbirn]

I've tried PC and conventional lube in all my .45-70s: groups from the Highwall and Trapdoor carbine are almost identical except the PC seems to shoot a touch higher (maybe an inch or two) at 200 yds from both rifles. On the other hand, my Pedersoli RB doesn't appear to like PC at all: same powder charge, boolits from the same batch; at 200 the rounds lubed with Emmerts dropped into the expected 3 1/2"-4" but the PC group opened up to more like 5"-6", centered around approximately the same POI. I used a 405 RN in the carbine and the 500 gr. 'Gov't' boolit in the Highwall and RB.

Bill