A good 44 Mag load goes sideways on me

[larryw]

I've been loading a light practice 44 magnum load using 12gr of BlueDot behind a 240gr RNFP plated bullet for quite some time (WLP, Starline brass, firm crimp at the groove). Stout enough to let you know its a magnum, but not punishing. Very accurate out to 50 yards in both my RedHawk and 1894.

But now all of a sudden, the load's gone bad and I'm getting nasty keyholing on roughly 1/3 of the rounds: when fired, they feel and sound the same, but the strike on the paper is way-way off POA (8"+ at 50 feet!) and the hole in the paper is usually rectangular and ripped. I'm pretty confident its not the bullets because this batch works fine in my other practice load (21gr of 296, same brass, primers and crimp). I've pulled apart and weighed a bunch of these 'bad' loads and the powder charge is within spec. Still have about 150 to pull apart: when the accuracy is this bad, shooting them is no fun.

These bullets have a pretty soft core and will keyhole if accelerated too hard using too fast a powder, if you use a slower powder, they're good up to about 1600fps. But you can also get them to keyhole at around 1000fps with a poor powder selection, I learned this trying to use N340 to achieve magnum velocities. I'm wondering if the powder is funky; has anyone had problems with BlueDot lately?

Any other thoughts?

thanks,
Larry

 

[JPM70535]

Larryw

I can't imagine Bluedot keyholeing using 12 grains behind the Bullet mentioned. I have used thatoad on numerous occasions with good results in my S&W 629. It always produces groups of 4 inches or less at 25 yards. The only flaw I have found with Bluedot is the excessive muzzle flash it generates with charges of 16 gr. or higher. If you had stated you were using cast lead bullets at 1100 fps or more I would suspect excessive leading, but with plated bullets I would tend to discount this as a possibility. I use WLP as well as Federal and Remington interchangeably with no differences in performance. Also I haven't heard of any changes to
Bluedot's formulation, although one thought just occurred. Does this batch OF Bluedot have the same # as the batch you used that did not keyhole?

Good luck in your search for an explanation

 

[Watchman]

Have you cleaned out your barrel lately ?

You may be to the point that the copper fouling is literally shredding your bullets.

I hadf a problem much like yours awhile back with my Anaconda. A good scrubbing took care of it.

 

[larryw]

I don't know the lot number of the previous batches and the lot number is illegible on this container: I can make out the last three digits, 258, but that's it.

Barrels of both guns are clean (that was my first thought too) and both guns shoot the 296-based load, as well as lead and jacketed loads just fine. At this point, I've ruled out gun problems (Shooter problems? Jury's still out, but it would be a real trick shot getting round bullets to leave rectangular holes. ).

 

[caz223]

Have you changed anything lately, like the crimp?
What are you loading on, progressive or single stage?
If progressive, are you crimping and seating in the same step?
Just some questions to try to get to the bottom of this...

 

[larryw]

Good questions:

- Loading on a Dillon 550B progressive.

- Seating and crimping (Lee "Factory Crimp" die) on seperate stations.

- I load several different bullets using this toolhead, but the only thing I change is the crimp. I've marked the crimp die's adjustment knob for each bullet. I measure the crimp and compare it to a 'master cartridge' before I proceed.

 

[Mal H]

I guess I'm as surprised at the results as anyone - but in the opposite direction. I'm surprised that you didn't experience keyholing with that load before. 12 grains of BlueDot is a light load for what is in essence a lead bullet. You should be getting less than 800 fps with it. It's possible that the load was always on the hairy edge of instability in the past and it has now crossed over the line due to a few things that are slightly different. What things? I don't know. Different temperature, different run of bullets/powder/primer, slightly different crimp, slightly different powder weight?

Load a few rounds with just a tad more powder and see what results.

Any way you can chronograph the bad rounds?

 

[larryw]

This is a load I got from an article John Taffin wrote a while back. When working it up, it chronyed at 950fps out of my RedHawk (he got just under 1000fps, musta been a longer barrel) and 1275 from my 1894 Marlin. I ran into keyholing problems as the charge approached 13gr with this bullet/powder combo: accelerating it too hard and beating up the heel.

I'm afraid of killing my chrony if I shoot these over it now.

It *used* to shoot real nice out of both rifle and pistol. This is one of those things that makes reloading so much fun.

 

[E357]

Just a guess but it might be the Factory crimp die causing a separation of the soft lead from the plating on some of the rounds - this would cause the instability. A number of the plated bullet brands are very picky about the crimping, although they are getting better.

 

[larryw]

That's a good thought; I'll call West Coast Bullets and ask them if they've had a bad batch. In the tens-of-thousands of their bullets I've loaded, I've only seen a few 'defective' bullets that I think were because of swaging problems. The plating on WCB is pretty tough, difficult to peel off with a sharp knife, which is in sharp contrast with the two other brands I've tried in the past.

Two factors make me doubt the bullet is the problem: in the cartridges I've taken apart, I haven't seen any problems with the plating; and the same bullets with the same crimp shoot great when run hotter in front of a different powder (21gr of 296).

Thanks for the suggestions guys, we'll get this thing nailed.

 

[caz223]

I've had that problem before, usually from crimping and seating in the same stage, but the lee FC die can certainly crush and undersize the soft plated bullets very easily if set for too much crimp.
My suggestion, try lightening the crimp a little bit, see what happens.
Remember, plated bullets are much softer than typical cast lead.
It could very easily be undersize bullets, see if just the projectile can be easily dropped through the barrel without forming some grooves.
You should need a hammer, and a wooden dowel.
Try measuring the diameter of the bullet before, and after running it through the barrel.

I've used around 12 grains of blue dot + lead in my .45 colt, it made for a very dirty, low pressure load.
It didn't even have enough power to expand the thinner .45 colt brass to form a uniform gas seal. All the spent cases had a black 'smudge' on one side of the case where the gas was leaking out.
This might cause tumbling.
I had powder flakes and black crap all over my arms and gun, too.
I changed to titegroup and unique for light loads in similar calibers, and the results were much better.
If you must stick with blue dot for your carbine, try adding a little more BD.
You might try faster burning powders for light loads in your revolvers.
Just a few suggestions.

 

[JohnK]

It *used* to shoot real nice out of both rifle and pistol. This is one of those things that makes reloading so much fun.

If it's shooting poorly from both guns now that previously shot it well and you have the dies locked down well on your Dillon I'd suspect a bad lot of bullets, powder or primers. If those bullets still shoot well with other powders maybe your can of Blue Dot has some contanimate and isn't burning properly.

 

[Chuck from arkansaw]

Your load is close to my favorite, 13 gr. of bluedot with a hard cast 240 gr. Lee tumble lube bullet. It has always been very accurate even out to 100 yards. I suspect the bullet or the crimp. Try some hard cast bullets with a roll crimp and see if the problem go's away.

 

[WESHOOT2]

So your gun CAN still shoot straight.

It CAN shoot this same bullet straight (21g W296).

And presumably you've changed NOTHING.

But something is wrong, very very wrong..........

Fixes: bump up your powder charge, change powder, switch to Federal 155.
Me has a slight suspicion you gotta batch o crap WLP's, maybe (other readers please don't go insane by this suspicion, 'cause I seen it before...).



General hint: get yerself a Redding Profile Crimp die, and learn to apply 'heavy' and 'medium-heavy' with it (the only two acceptable modes).

 

[larryw]

I'm starting to suspect a bad batch of WLP myself as I've had some strange happenings in 45ACP using primers from the same lot.

I got the Lee Factory Crimp Die on your recommendation and now you're telling me the Redding Profile Crimp is what I need? OK, I'll do that, but would you please quit changing your mind?

For my own education, what makes the Redding Die better and how do I know when I have properly applied a 'heavy' and 'medium-heavy' crimp?

thanks,
LW

 

[WESHOOT2]

TACITURN VERMONTERS

The LEE die is mandatory for auto-feeder cartridges; the Redding Profile Crimp die is for straight-wall revolver-type cartridges.

The Redding die starts with a gentle taper and finishes (sounds like I'm talking about wine, eh?) with a very symmetrical roll. It aligns the bullet nicely before it pushes the mouth in.

"Heavy" and "medium-heavy" are hard to describe; much is feel and experience.
You ideally have about .002-.004" of case actually pushed into the bullet cannelure, with its appearance parallel to the case body.
That's "heavy".

"Medium-heavy" is just the mouth 'roll' into the cannelure.

 

[SASS#23149]

WESHOOT2
the Lee dies are caliber specific....my .45 colt FC die puts a beautiful roll crimp on the brass.The ones for ACP put a nice taper crimp.If he has the right die it should make the correct crimp,no?

 

[WESHOOT2]

NOT ALL ANYTHING ARE CREATED EQUAL

No.

The Redding does a better job.

On hand: LEE, Lyman, Redding, RCBS, Dillon, Hornady.