Question on stability

[PacMan]

Just starting to work on some loads using a 170gr Keith type bullet. Loaded it over 5 gr of TightGroup for a average of 947fps in a 4" Smith.
3 of the seven rounds apeared to be tilting at 25yds. They had tears on the top side of the hole.
The bullets were just cast and WD but not harrdened to any extent.
Should that bullet need more velocity to stabilize and if so will it again become unstable when it drops back to the 950fps? I can only assume that it will.

Any advice willbe welcome.
Thanks
Pac

[williamwaco]

That is a very popular bullet.
You should not have any stability issues at any velocity.

[subsonic]

Back up to 50yds. If they are tilting at 25, they will be flipping at 50.

It could be an issue with rifling stripping, not just too heavy for twist. Check hardness/toughness and diameter.

Waco is right that that the 358429 Lyman is a popular boolit - but you don't mention exactly what boolit you have. "Keith type" can be pretty open-ended.

What does the crown look like?

[PacMan]

Well it is Keith style in nose only. I had Veral cut the nose to crimp at .37 so it would work in my GP100 and newely aquired 686 Smith.
Here is a bad picture but it is all i got at the time.

[PacMan]

I had Veral cut the ring on the nose so i could easily tell it from another Keith when loaded.

[subsonic]

What alloy?

did you only shoot 7? 7 shooter S&W?

[PacMan]

Sorry to many distractions around here.Had to catch my grand daughters dog.

Alloy is WDWW but cast for less than an hour. Should be good to go tomorrow as far as hardness.

Bullets are sized to .3575 which will not pass through the throats. Pin gauges put the throats at a tight .357. Have not sluged the barrel yet but the gun does real well with the 160 GR LBT FN at 1300 fps.

Only 7 and had company then it got dark. Yes it is a 7 shooter. 686Plus 4".

[ReloaderFred]

Is the target tight against a backboard, such as stiff cardboard? If not, that will cause tearing of the hole, no matter what the bullet. Loose paper just won't allow a clean cut hole.

Just a thought, since many a bullet gets blamed for keyholing, when it's the loose target that's at fault.

Hope this helps.

Fred

[PacMan]

Is the target tight against a backboard, such as stiff cardboard? If not, that will cause tearing of the hole, no matter what the bullet. Loose paper just won't allow a clean cut hole.

Just a thought, since many a bullet gets blamed for keyholing, when it's the loose target that's at fault.

Hope this helps.

Fred

Yea my old backboard is shot away to nothing.I thought about that and it could be the problem but this is the only bullet that has shown any signs of tipping.
You have inspired me to go ahead and do what i have been putting off.
thanks
pac

[subsonic]

It's probably not tipping. Shoot more, further, and with a better target backer.

[44man]

That is a long boolit so YES, it needs shot faster. You are under spinning it.
50 yards to 100 yards will really show you.
True that loose paper will show bad stuff yet I bet you ARE getting tipping.
Spin does not drop as fast as velocity so even when the boolit transitions velocity over distance, it should still be stable.

[bobthenailer]

I get excellent accuracy with 4.5 grs of Tightgroup with quite a few different cast bullets from 158 to 180 grs , loaded in of 357 mag cases . from at least 7 different firearms.

[Thumbcocker]

My stability has been questioned more times than I can count by SWMBO