BULLET INSPECTION NEEDED

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  • Last Post 16 January 2018
joeb33050 posted this 11 January 2018

 

BULLET INSPECTION NEEDED

 

Jacketed bullets shoot much more accurately than cast bullets, and I’m trying to find out why. I’ve been shooting a lot of jacketed bullets at lower velocities. All .22 cal bullets, that stabilize, shoot accurately; except the .22 cal fmj cannelure bullets. These never shot accurately in the past, either.

 

The ARMSCOR 55 gr fmj cannelure bullets, three 5-shot 100 yard groups, shot very poorly.

 

Weights of the remaining 85 varied from 54.9 to 55.9 gr, clustering around 55.5 gr.

 

EX: Nosler 40 gr Varmageddon bullets weigh 40.0 grains, almost all. Data available.

 

If the BULLET determines accuracy, then there’s something about these ARMSCOR bullets that makes them inaccurate. 34 of them weigh 55.5 gr; I’ll shoot some of them to see if they’re accurate. But, I’d like someone to inspect/measure some of these outliers to see what’s different/off. Anyone?

 

joe b.

 

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RicinYakima posted this 11 January 2018

Joe, I'm game to try to  find out what the difference is.

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TRKakaCatWhisperer posted this 12 January 2018

 

BULLET INSPECTION NEEDED

 

Jacketed bullets shoot much more accurately than cast bullets, and I’m trying to find out why. I...

joe b.

 

An anecdotal answer, based on one conversation back more than 40 years ago.  I sent an inquiry to a bullet manufacturer - a post card - asking whether the 6 radius was more or less accurate than the 7 diameter radius ogive.  I got a PHONE CALL - lasted 20 minutes!  He mentioned that he'd had some issues with accuracy early on in his manufacturing - said he had been watching thousandths and should have been more carefully watching ten-thousandths.  That was Jim Berger - maker of some mighty fine bullets! 

 

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joeb33050 posted this 12 January 2018

Ric;

Please pm your address.

Thanks;

joe b.

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Ken Campbell Iowa posted this 12 January 2018

...at this time ... at the risk ... certainty ... of being boringly redundant ... we must remember that:

all equally perfect mj bullets are not equally accurate at the target ....

?? because?? ...  ??they are not a match that suits that chamber ??  and/or ... 

my beloved 7mm rem. express shot 3/4 groups with perfect hornady 120 gr... and almost 2 inches with perfect 163 gr. match bullets ...  

my 222 shot 0.6 with scraggy 54 gr. sisk; no two noses alike ..... ... but 1.5 with perfect sierra anything ...

so if we sorted sierra but not sisk it would look like sorting makes for worse accuracy at the target .... samples of n=1000 would be highly confident ...

*******************

maybe our rubbery cast bullets change their shape in various ways as/when they are shot ....  one shot a hornady, next shot a sierra ... so to speak ...

and that is even IF  they are weight sorted .....     

ok, ok, i believe that perfect-before-ignition  lead bullets are more accurate than imperfect lead bullets ..... if everything else IS equal .... so::

i think joeb is showing that everything else is NOT equal ...

and larry is showing that you can make everything else .... MORE equal ... and start to see that thin advantage of perfect-before-firing castings ... 

keep it up guys, i think the truth travels at 3600 fps, and it is kinda hard to read as it zips by ...

thanks, ken

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RicinYakima posted this 12 January 2018

 Ken, My hypotheses is that the cast bullet changes shape when fired, especially when it has to jump from case to bore. And then the center of form and center of mass of different for each bullet. However, I have never figured out a way to test that hypotheses.

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BigMan54 posted this 13 January 2018

Thanks a lot guys, now I'm more confused about accuracy then ever.

One thing I do know, don't ever expect foreign made FMJ to shoot for beans. Although I've never loaded/shot NORMA OR RWS/DWM FMJ's.

However the stubby little LYMAN SWC #452488 is basically two wide driving bands with a grease groove. I shot some fantastic groups over 3.5grs of BULLSEYE out of a Gold Cup when I was young. I sorted those bullets cosmetically both before and after going through the Lube-Sizer. Weight sorted too. Still have that pair of 2cavity molds I used. Out shot both WIN & REM factory match. Can't imagine a bullet like that changing shape. Used to mine the lead after shooting into the dirt bank. All recovered bullets looked the same to me.

 

 Pachmayr had reworked that gun for my Dad. Back in the OLDEN DAYS when August and Frank were just running one of Los Angeles' Premier Gun Stores/ Gunsmithing Operations. A PLACE little boys could dream in. In fact the gun may have been a COLT NATIONAL MATCH. 

Maybe that's why the HORNADY 117gr Spire Point shoots great in my old Vanguard .25-06 and the 120gr Hollow Point shoots like a shotgun pattern. 

Long time Caster/Reloader, Getting back into it after almost 10yrs. Life Member NRA 40+yrs, Life S.A.S.S. #375. Does this mean a description of me as a fumble-fingered knuckle-draggin' baboon. I also drool in my sleep. I firmly believe that true happiness is a warm gun.

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joeb33050 posted this 16 January 2018

I BOUGHT HORNADY 55 GR FMJBT CANNELURE AND HORNADY 55 GR SP CANNELURE AND SHOT THEM TODAY OVER 8.5 TITEGROUP, 5 SHOTS, 100 YARDS, STRIKER SAVAGE PISTOL. 3 GROUPS EACH.
ARMSCOR 55 GR FMJBT CANNELURE 2.35, 2.4, 3.05 INCHES AVG 2.67, sorted to +/- .1 gr
HORNADY 55 GR FMJBT CANNELURE .775, 1.3, 1.2 INCHES AVG 1.105
HORNADY 55 GR SP CANNELURE .7, 1.2, 1.475 INCHES AVG 1.092

So, it may not be the cannelure, or the bare lead on the base, or the boat tail.

If a bullet is dropped in water/oil, and it's out of balance, will the light side be up when it gets to the bottom?

joe b.

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