k98 boolits tumble

[legend]

i took my camper to the mountains today (black hills ) and shot my k98 into a stump at about 60 yards,my load was 249 grain maximum, 17 grains of 2400, winchester large rifle primer. this combo has shot fair at 30 yards,but, today the boolits tumbled.

so, whats cooking? should i step up the speed ?

boolits measured .3256 and are about a thousanth undersize for the bbl.


I was going to use it for whitetails on thursday,but, i now dont have time to play with the load.I will use my rem 700bdl with 311299 at about 1800 fps...it shoots well.

any thoughts ?

[I'll Make Mine]

That's a lot of boolit to try to stabilize at what can't be 1600 feet per second. Small changes in conditions (temperature, elevation, wind) might be enough to destabilize the bullet if they're marginal to begin with. Try either a shorter/lighter bullet, or more speed, or both. You might also want to size larger, up to .001 or .002 above groove diameter, if your rounds will chamber that way; you'll get less leading as well as likely improving accuracy.

[felix]

You are obviously not getting full twist from that barrel to that boolit size. ... felix

[swheeler]

i took my camper to the mountains today (black hills ) and shot my k98 into a stump at about 60 yards,my load was 249 grain maximum, 17 grains of 2400, winchester large rifle primer. this combo has shot fair at 30 yards,but, today the boolits tumbled.

so, whats cooking? should i step up the speed ?

boolits measured .3256 and are about a thousanth undersize for the bbl.

I was going to use it for whitetails on thursday,but, i now dont have time to play with the load.I will use my rem 700bdl with 311299 at about 1800 fps...it shoots well.

any thoughts ?

There's your problem, undersize bullets

[legend]

thank you for answering,

the same size booiit but at 170 grains ,same powder charge etc does not tumble,so am i to understand that it is pushed faster and thus upsets better?

Felix, i dont quite understand what you ment. would you please expound ?


sounds like i need to hone out my sizer die...thats an easy fix i think.

[runfiverun]

felix said your boolits are too small.
they ain't grabbing the rifling.
so they aren't spinning fast enough to stabilize.

you have more bearing length on the longer boolits and they aren't stripping as badly so are being stabilized better.
i'm surprised you don't have leading down the rifling edges.

[MBTcustom]

What R5R said X2

[MtGun44]

Fatter boolits would be my first thing to try.

Bill

[williamwaco]

i took my camper to the mountains today (black hills ) and shot my k98 into a stump at about 60 yards,my load was 249 grain maximum, 17 grains of 2400, winchester large rifle primer. this combo has shot fair at 30 yards,but, today the boolits tumbled.

so, whats cooking? should i step up the speed ?

boolits measured .3256 and are about a thousanth undersize for the bbl.


I was going to use it for whitetails on thursday,but, i now dont have time to play with the load.I will use my rem 700bdl with 311299 at about 1800 fps...it shoots well.

any thoughts ?

I would be shocked if that bullet didn't tumble.

The conventional wisdom is that bullets should be one to two thousandths larger than the groove diameter.

In my experience, I have ALWAYS found best accuracy with least leading with a properly lubricated bullet .003 over groove diameter - in rifles. I get good results with .002 over in handguns.

( I have NO personal experience with your exact rifle / bullet combo)

[MBTcustom]

Williamwaco, dont you mean .001-.002 over Groove?

[williamwaco]

Williamwaco, dont you mean .001-.002 over Groove?


Ooops!

You are correct.

[legend]

thank you all,i understood it was too small....but the lighter boolit sized the same did not and thought i would try it on paper first,glad i did.

no shooting on whitetails yet,and am going up again for four days starting thursday.
hopefully the rut will start soon.


i saw a monster whitetail on a full tilt run through the woods......mountain lion?could be.


i will start working on the sizeing die.

[TCLouis]

Sit both boolits on their bases side by side . . .

Notice the difference in length ? ? ?

That is one of the issues, push the longer boolit harder and it may stabilize.

[legend]

back from hunting whitetails,311299 did the job just fine ! i shot a twopoint yesterday as we have few bucks around this year,i can usually find a 4-5 point each year(per side) but not with the large mountain lion population we now have...shot was about 90 yards centerpunched his neck, it looks like a two year old.


i am happy for the meat.

[Four Fingers of Death]

"i am happy for the meat. "

Always a thing to be grateful for!

[Larry Gibson]

thank you for answering,

the same size booiit but at 170 grains ,same powder charge etc does not tumble,so am i to understand that it is pushed faster and thus upsets better?

Felix, i dont quite understand what you ment. would you please expound ?


sounds like i need to hone out my sizer die...thats an easy fix i think.

The 170 gr bullets are shorter and will stabilize in that twist at a lower velocity than the heavier and longer bullet. Additionally the same charge will drive the lighter bullet faster increasing stability. Given the same powder charge and the same alloy the heavier bullet will upset better because it has more mass to resist accelleration. With the heavier bullet I would suggest a medium burning powder in the 4895 burning range and push it to 1800 fps or so for hunting. A softer alloy will also be benificial to obtirate to fit the barrel or "bumping up".

BTW, as mentioned, going to the mountains probably in colder weather also dropped the velocity further reducing stability.

Larry Gibson

[legend]

larry, thank you. you brought up the colder temp in the mountains,and i would not have thought of that.

I already had plans to try 4895 before you mentioned it, i plan to work with several different powders this year to get away from the small charge pistol/shotgun powders i have mostly used. and i have that jug of 860 just begging to be used in something; the 8mm k98 with the maximum boolit might just be the combo.

i was glad i found that it tumbled at about 60 yards,it was a little tap on the head telling me that this combo will not work.

thanks for your help.