Bullet balance

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Last Post 31 January 2015

Standard Member

bandmiller2 posted this 14 January 2015

Sitting on the can this morning thinking, yea I know. I think most bullet inaccuracy is caused by unbalanced or out of round slugs. What if you had two accurately machined counter rotating wheels close and dropped a bullet between them. If it spins true balanced if it wobbles or jumps around not. Do you think this would have any merit.?? You may need a rheostat to ramp up the speed. Frank C.

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Standard Member

onondaga posted this 14 January 2015

Vivid on the can thinking there. Good molds that cast round bullets is much more practical and easy. Can the crappy molds and get good ones.

Gary

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Standard Member

bandmiller2 posted this 14 January 2015

Correction both drums would need to turn the same direction. Cast bullets would need to be pushed through something like a lee die as any flash would skew the results. May work for void detection or unbalanced jacketed. Of course it may not be worth the trouble. Frank C.

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CBA Member

Ken Campbell Iowa posted this 15 January 2015

of course, after spin testing a perfectly balanced bullet, you still have to get it to stay that way thru the first inch or so of it's travel. we really need to sort the bullets after they leave the muzzle ... oh wait, i guess we do that already ...

my personal plan to win matches is to put up a tool steel ” wind flag ” about 25 yards downrange ... with a 0.4 hole in it ... if i shoot enough shots, should result in a 1/2 inch group at 100 yards

ken

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Standard Member

TRKakaCatWhisperer posted this 15 January 2015

Ken Campbell Iowa wrote: of course, after spin testing a perfectly balanced bullet, you still have to get it to stay that way thru the first inch or so of it's travel. we really need to sort the bullets after they leave the muzzle ... oh wait, i guess we do that already ...

my personal plan to win matches is to put up a tool steel ” wind flag ” about 25 yards downrange ... with a 0.4 hole in it ... if i shoot enough shots, should result in a 1/2 inch group at 100 yards

ken That's be best use of statistical sorting I've heard of in a LONG LONG time!

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CBA Member

Brodie posted this 15 January 2015

Ken: Would not a .4 inch group at 25 yards (which is what the .4 ” hole amounts to) translate into a 1.6” group at 100? Brodie

B.E.Brickey

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Standard Member

TRKakaCatWhisperer posted this 16 January 2015

Old Coot wrote: Ken: Would not a .4 inch group at 25 yards (which is what the .4 ” hole amounts to) translate into a 1.6” group at 100? Brodie Depends on the caliber. If the bullet touches the edge it'll be deflected - not observable because from Podunk Center it would end up in Jones County.

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CBA Member

Brodie posted this 16 January 2015

Quite true. But, you will always shoot a smaller group at 25 than at a further distance even if the bullets do not touch the edge because of the cone of dispersion of any gun. Trying to make that cone smaller is what we are trying to do. Brodie

B.E.Brickey

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CBA Member

Ken Campbell Iowa posted this 16 January 2015

dang !! it didn't occur to me that anybody would actually THINK about my windflag scheme ...

anyway, for a 0.300 bullet, it could only vary 0.050 radius or 0.1 diameter at 25 yards ... and so the cone of impact dispersion would be 0.4 at 100 yards ...

hmmm .. ok, interesting about the effect on wind dispersion ,,, i think ( owch ) it would be as if the muzzle was only 75 yards from the target.

geeeeeze, how boring can January be ?

ken

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Standard Member

TRKakaCatWhisperer posted this 17 January 2015

Ken Campbell Iowa wrote: .... geeeeeze, how boring can January be ?

ken
Around here the mating season for skunks is just beginning (late Jan early Feb). Trapping them is always a challenge - need to keep the rabies under control ! Pictured is one from the summer - in my 2015 Skunk Calendar (Miss September).

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CBA Member

muley posted this 17 January 2015

would make a nice hat for rondyvooing.

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Standard Member

bandmiller2 posted this 17 January 2015

Reminds me of my yard skunk “whitie” I find him in the trap open the door and he would sleep in the trap all day then leave next night. This went on three or four times finally gave him a ride to a new home a yuppie town that likes little furry animals. You may want to mount the trap on a piece of plywood larger than the trap to keep the varmint from dragging in a half yard of loam. Frank C.

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Standard Member

M. W. Curtess posted this 18 January 2015

To modify a Jerry Clower (one-time popular red-neck stand-up commedian) line: “Is they a wrong way to kill a skunk?” Dissenters have never had a road-kill up in the engine compartment of their car - or one “lit off” in the crawl space under their house. (instantly no longer so “loveable” and “mis-understood".)

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Standard Member

M. W. Curtess posted this 18 January 2015

More closely define “out of round” please? To my utter amazement, I found that bullets from slightly laterally-shifted mis-aligned blocks, while being significantly out of round, shoot as well as any other, in even-number groove barrels. Inherent dynamic “balance” is not affected. Such moulds are easily corrected, which I always do - but still, ----------??? Very early in my bullet casting “experience", I read somewhere about random “voids” in CB's, that created dynamic imbalance. Suddenly aware of the issue, I could then even see surface voids on some of my (very earliest) bullets. My approach to testing for imbalance was to acquire a 36” length of ordinary window glazing, mounting it at an incline which would just compel sized CB's to roll down it, and listen to the sound as they progressed toward the folded towel at the bottom. Certainly, this was quite impressive - but - has little relationship to the performance of a fired bullet at the much, much faster rotational speed - where “resonance” and “harmonics” come into play. (Something I know fundamentals of, from the days when I was professionally involved with gas turbine powerplant maintenance.) As a result, just as championship-class CB shooters have discovered that superficial casting defects need not have any measureable effect on bullet accuracy, I have the notion that: (considering the rotational RPM we deal in), only really gross imbalances (unlikely in experienced bullet caster's production - especially if “uniformly frosted") could affect CB accuracy. Never mind Dr. Mann - who dealt in extremes never encountered in ordinary shooting.