Why are my bullets tumbling?

[twister]

I shoot a 686 with a Clark ppc barrel installed on it, and just recently I have like 1 bullet out of a hundred tumble. The load is 5.1 of 231 with a 125 grain hollow point bullet. I shoot this gun in a ppc league, and the gun and my bullets have always worked fine until recently. Any one have any ideas on what happened? Thanks for your help, Dave.

[Waltermitty]

Check bullet diameters. Check about 100. 

[Mover480]

Reminton brass?

[Tophernj]

Check the barrel for fouling?

[RePete]

Are the bullets lead , plated, coated, FMJ HP?

 

Too much crimp.

 

Crap brass.

 

Inconsistent  bullet diameters.

[twister]

I’m using all the same brass, Zero 125 grain jacketed hollow points. It’s the same combo I’ve been using for 4-5 years now. But, for some reason the single tumbling has started for no apparent reason.

[Waltermitty]

9 minutes ago, twister said:

I’m using all the same brass, Zero 125 grain jacketed hollow points. It’s the same combo I’ve been using for 4-5 years now. But, for some reason the single tumbling has started for no apparent reason.

 

So something has changed. Anecdote: once upon a time I got a box of Zero bullets that started tumbling "for no apparent reason." I measured them and found undersized bullets in the box.

 

Are you looking for answers different than the ones you've received so far? 

[Tophernj]

How many rounds down the barrel?

 

I don’t know what the deal is with pistol barrels,  but rifle barrels are a consumable item. Is it possible you shot the barrel out?

[Toolguy]

It may be possible that some 9mm bullets got mixed in with the .357 bullets. There are 125 grain ones of both. Go through them with a caliper and you will find out.

[twister]

Thanks for all the replies, I’ll be going through my bullets with a caliper and checking them all before loading. The barrel does have a lot of bullets through it, but it’s a tack driver 98 percent of the time.

[Toolguy]

If it's a tack driver most of the time, it's not the barrel.

[twister]

Toolguy, I tend to agree, I guess I’ll be checking bullets for a while!

[Tophernj]

Good deal and good luck.  

[pskys2]

18 hours ago, Tophernj said:

Check the barrel for fouling?

There was another thread recently about a similar problem.  Gun went from great to tumbling.  After a bunch of us had offered ideas it came back that his barrel was leaded.

He cleaned it and the problems went away.

If you shoot PPC, isn't a popular load 148 wc's mostly lead?

If a good cleaning doesn't help, check for crimping issues.

Or are all chambers still timed good?  If you have a couple of ratchets worn/chipped causing late timing the bullet can scrape the forcing cone.  Usually it will be noticeable in slow fire, inertia of the cylinder in faster firing tends to mask the issue.  I don't think I've ever had it cause tumbling, usually just affected accuracy but worth checking.

[twister]

Yes, a lot of ppc shooters shoot lead, I shoot 125 grain zero jacketed hollow points as I also shoot action pistol, so I need these bullets to meet a power factor. I use 5.1 of 231  Winchester powder.