Expected my 50-70 to "boom" - it cracks - why???

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Whelen B

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Been shooting my 50-70 all year at the range and it's a 140 year old pussycat to shoot. It's great. I always have used good ear muffs and so somehow just imagined it to have a great gentle giant "BOOM" report.

However yesterday I shot two rounds in a wilderness area at a target sans muffs - to confirm zero in preparation for a bear hunt. It was still perfect but was I ever suprised by the sharp "crack" report. Sounded to me like a much smaller calibre though I know this is all somewhat subjective.

The rifle has a 29" barrel and am using 450gr cast bullets and 36grs BH209. It chronos as it should at just over 1120MV so all is well. Pressures should be about 18000 psi or so.

Just wondered why my 50cal "buffler" sounds like a dinky bore. Any ideas?
 
I use a downloaded smokeless load(can't remember the amount at the moment) with 4198 and toilet tissue wad in my 50/70 remmy rolling block, gets me a 1200-1300 ft with 350 grain bullet and it gives a nice boom with accompanying thump to the shoulder. For my gun this is a very accurate load and very pleasing to shoot.
 
Have you ever shot it or heard it shot without hearing protection? I'd bet this is simply an issue of perception.
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That is what I meant above "sans muffs" - that means "without muffs". Yes and I perceive a notable and unexpected "crack" - like breaking a huge dry stick - not a boom - that's my point. I spent my life shooting/hunting much smaller bores and find even they do not generate such a crack. I don't wear muffs at all hunting.

Was thinking about it today and wondered if being right on the sound barrier threshold might be a factor? Loads chrony around 1120+.

What flavour is your .50-70?
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Remington roller made in Ilion in 1868 - rechambered Swedish 12.7x44R with original barrel. Still has the original hammer and breech block. Chambers easily now seated .515" bullets with Starline 50-70 brass.
 
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The ear muffs will attenuate the higher frequencies more than the lower ones and the round may be super-sonic depending on conditions. Have someone shoot your rifle in an opposite direction while you stand 100 yards away and see if this makes a difference to the sound.
 
I was all set to express my condolences - when I read the subject line I jumped to the conclusion that the gun itself had cracked i.e. broken. Whew!

I've shot my Swedish m1867 12.7x44R with 450gr bullets, using Pyrodex and also with some smokeless loads, e.g. 24gr SR4759. Even with earmuffs, I've noticed something of a different character in the sound produced. There's a difference in MV according to my chrony (5-shot averages: Pyrodex 1155 fps, versus 930 fps with 24gr SR4759).
 
Thanks TJ - very good of you to donate to the experiment. Your BP loads seems about a perfect top load - from my reading on these old antique 50-70s. In the past I have used very light 50gr BP duplex loads but was wearing muffs (chrony readings of 934, 912, 937 at a cold -15C).

Also was just wondering how you arrived at and measured out that 66.6 grains?

FWIW I throw a 100 by volume with a commercial muzzleloader measure first and then weigh it on my scale. Knowing that weight I can then calculate any BP charge's actual weight and use my scale to weigh each BP charge going into the case. Assuming you would do something similar.

PS - check out the drop of my present loads past 100yds - http://35cal.com/my50-70_ballistics.html
 
Whelen B said:
Thanks TJ - very good of you to donate to the experiment. Your BP loads seems about a perfect top load - from my reading on these old antique 50-70s. In the past I have used very light 50gr BP duplex loads but was wearing muffs (chrony readings of 934, 912, 937 at a cold -15C).

Also was just wondering how you arrived at and measured out that 66.6 grains?
FWIW I throw a 100 by volume with a commercial muzzleloader measure first and then weigh it on my scale. Knowing that weight I can then calculate any BP charge's actual weight and use my scale to weigh each BP charge going into the case. Assuming you would do something similar.
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Thats how much powder the case took, with that bullet and 0.1 inch of compression. Used an adjustable brass dipper to get it up to about 65 gr, then dribbled the rest using my fingers. Electronic scale. Also used a 30" drop tube
 
use blackpowder , if a boom is what you want ,, probably more accurate as well after you learn to shoot it ,,wade
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Not really "after" a boom - just expected one so was wonderin. However I am after accuracy and most everyone claims BP will offer the best likely.

Gonna do some tests with my own and TJ's BP loads - maybe tomorrow if I find time. I'll report back. Today I'm bear huntin with my BH209 loads (home on a lunch break now) and don't have time today to run meanungful tests and clean BP residue from the bore.
 
Whelen B said:
Not really "after" a boom - just expected one so was wonderin. However I am after accuracy and most everyone claims BP will offer the best likely.

Gonna do some tests with my own and TJ's BP loads - maybe tomorrow if I find time. I'll report back. Today I'm bear huntin with my BH209 loads (home on a lunch break now) and don't have time today to run meanungful tests and clean BP residue from the bore.
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You hunting that stand by the river where we have the excavator working?
 
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