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PBSmith
12-22-2019, 07:46 PM
My group fliers with a .30-30 lever are yawing ever so slightly. Typically I'll see 3 or 4 shots in a cloverleaf and a flier 1" out. Range: 25 yds. Bullet weight is 180-185 grains. I'm shooting light loads of fast burning pistol and shotgun powders (6.5-8.0 grs) and also light loads of AA5744 (12-14 grains).

Will increasing the powder charge take care of the yawed fliers?

If not, what are the other possible causes?

Thanks.

jimb16
12-22-2019, 08:00 PM
It should. The description you gives indicates marginal stability. At longer range all of the shots would probably show yawing and tumbling. Increase the charge by 1 or 2 tenths and it should disappear at least a short range, but I think it would still be a problem at longer ranges.

leadhead 500
12-22-2019, 08:02 PM
A couple things might be going on. One is bullet not being sized to large enough diameter, also gas checks coming off can cause problems. What diameter are you sizing them?

PBSmith
12-22-2019, 08:55 PM
A couple things might be going on. One is bullet not being sized to large enough diameter, also gas checks coming off can cause problems. What diameter are you sizing them?

Sizing to 0.311."

turtlezx
12-22-2019, 08:59 PM
see if it will chamber .312 of .313 if so shoot it

RickinTN
12-22-2019, 09:02 PM
Are you shooting a Winchester, Marlin, or other brand? The Winchesters have a 12 twist, the Marlins a 10 twist.
Rick

GONRA
12-22-2019, 09:03 PM
GONRA suggests (if you can!) retesting at 50 yards, maybe 100 yards too. May be better!

Texas by God
12-22-2019, 10:06 PM
SO- the bullet holes show tipping? Or does the flier show tipping?

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MT Gianni
12-23-2019, 12:37 PM
The bullet should be asleep by 25 yards but may not be. Test again at 50 or longer and as said increase charges.

popper
12-23-2019, 01:03 PM
Could be powder, bullets or lube. Very common with grease/wax lubes. Light loads can be position sensitive, changing the burn. Tipping is usually stability, dacron filler may help burn problem. Flier is normally a bullet/lube problem. Lube can fly off unbalancing in flight. PC appears to reduce the problem but it still shows up once in a while. Could be just a non-flat base. I pushed some PB PCd hard from a BO carbine, got a nice circular 1" pattern @100. Base not quite perpendicular to the bullet centerline. Doesn't take much. I was experimenting with sprue cutting, IMHO cutting real cold caused the plate to rise a bit at the end. A non-square GC will do it too. Set the cast base down in a row on a flat surface, something with straight edge to align the bases. Look at the tips for and out-of-align one. The base of the bullet does all the steering when it exits the barrel crown. A few feet after the muzzle it's all gyro action.

waksupi
12-23-2019, 01:19 PM
Probably undersized. I doubt it is lube purging, if you are starting with a clean barrel. It seems like I would get lube purging after 10-12 shots, until I got figured out the amount of lube to use for a particular bullet.

GregLaROCHE
12-23-2019, 05:44 PM
With that heavy of a boolit and fast powder, are you trying to shoot subsonic ? A friend and I have been trying to work up a subsonic load for a .308. Heavy boolit with light charge of fast burning powder. We often had tumbled flyers at 50 meters. Many powders are designed to work at a minimum pressure. If you go below those pressures, you can have erratic burn rates effecting muzzle velocity.

PBSmith
12-23-2019, 10:12 PM
Are you shooting a Winchester, Marlin, or other brand? The Winchesters have a 12 twist, the Marlins a 10 twist.
Rick

Mossberg-made. I believe the twist is 1:12.

PBSmith
12-23-2019, 10:15 PM
SO- the bullet holes show tipping? Or does the flier show tipping?

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My grouped shots cut round holes. The flier is always showing evidence of tipping/yawing - not tumbled but what you might call "unstable." These holes are slightly out-of-round.

PBSmith
12-23-2019, 10:20 PM
With that heavy of a boolit and fast powder, are you trying to shoot subsonic ? A friend and I have been trying to work up a subsonic load for a .308. Heavy boolit with light charge of fast burning powder. We often had tumbled flyers at 50 meters. Many powders are designed to work at a minimum pressure. If you go below those pressures, you can have erratic burn rates effecting muzzle velocity.

No chrono here but I suspect the loads I've been shooting are subsonic.