Fliers ??????????

[Darrell Davis]

Veral,

Working with my new 350gr WFN LBT in my RUGER #1 45/70, and find that I am having some fliers.

I have been casting with wheel weights. Air cooled

I have begun to Weight my bullets, no luck.

Cast earlier this week, adding 20% line-o-type, air cooled, no luck.

Sizing , .459

The barrel is really nice on this rifle!!!!!!

Did need to have the throat opened just a tad, and there was zero throat.

I will Shoot a nice huntable group and throw one out.  Or put three almost in the same hole and a couple out.

Have thought about going to .460 for sizing as this would leave the bullet almost as cast.

Presently the best load I have found is 50gr. of IMR 4198 which is giving very consistant velocities and doing +/- 2150fps.

Comments?

Thanks

Darrell  The Crusty Deary Ol'Coot (CDOC) 

[Veral]

  Check bullet bases for squareness, which you'll probably have to do visually.  They all need to look the same, as one out of square the the bullet goes off coarse.

  I recommend fat bullets for 45-70's and that works best if the barrel is centered with the chamber.  If it isn't, and a few are, you'll get fliers, and accuracy will tighten if bullets are sized close as you an to groove diameter and made good and hard.  At least 20 bhn, but better oven heat treat up close to 30 so they can bounce from the chamber over to the rifling with the best precision possible.

  That bullet is a pumkin ball, so velocities might have to be up there to get them stabilized.  If you are running at the threshold of stability, you can expect any imperfect bullet to leave the group, and if that is indeed the problem, moving your target out to double the range you are shooting will make them fly like buckshot from an improoved cylinder bore with a dent at the end.

[Darrell Davis]

Thanks Veral!!!!!

I hope to have the stability thing in hand, as I am putting them over the sky screens at 2150 +/-fps.

Velocities are very consistant, in fact surprisingly so!

I have thought about going up to .460 from the .459 I am using, and I will make another run with harder/quenched bullets.

At .460, the bullet would almost be "as cast."

The bullets all appear to have edge to edge square bases, but I have noticed some bullet bases are slightly concave - not hollow or a big hole, just slightly concave but with a normal looking sprew etc.

This is an even concaveness across the bullet base, leaving a sharp and well filled out edge to the bullet base.

I noted this last time, that the alloy did not want to build up on the sprew plate to the normal thickness.  Possibly because of the addition of 20% linotype .?.?.?.?.......

This concave thing sounds like shrinkage to me??.

I was making an effort to keep the alloy temp between 6 - 700degrees, using a thermometer for the first time ever, and allowing the mold to cool between pours to keep frosting to a minimum.

Thanks again for your reply.

Darrell,  CDOC

[Veral]

  The concave is definately shrinkage, and it happens because the sprue dried up in the sprue hole before the bullet had finished drawing from it.  Perhaps your problem is not filling the sprues as high as you can, so heat is retained till the bullet can completely solidify while the sprue is still molten, and can supply lead to fill the shrink.

  Hope you can get your arms around all those words.  -  What I often do when putting out maximum effort to produce perfect bullets is to tip the mold a little just as the sprue fills and keep the bottom pour spout running so the stream flows into and runs the sprue cavity over and flows off the forward left corner.  Into a wide shallow cup I keep under the spout to catch runovers and drips.  This keeps a very liquid stream of alloy running into the sprue hole until the bullet is solid and finished drawing lead to fill voids and prevent shrink cavities.

[Darrell Davis]

Thanks again Veral,

I have the pot heating up as we speak, so will soon be cast'in.

Bottom pour pots and I don't get on well, so I use a bottom pour ladle.

This last try when I got the concave bases, I just couldn't seem to get my normal amount of alloy on the top of the sprew plate.

I am going to see if a slightly lower temp will work today.

later,

CDOC