32 gr Sierra BKs keyholing, problem with bullet or with gun?

[sharptailhunter]

I'm shooting a Savage Fv12 with a 1:12 26" bbl. My attempt at using the 32 BKs had keyholes using RE-10X well within Sierra's load data. Tonight, I was getting em again using IMR 4895. Again, the loads were all within published load data. Ironically, my best 5 shot group had three shots touching and then two keyholes on the backer board. I have shot reloads using V-Max (32&40), Nosler 32, Sierra 39, and Custom Reloading Tools new 34 gr bullets and never had a keyhole. I've also shot factory Remington 40 gr without any trouble. It's odd that it'd be a 32 gr bullet that is key holing, especialy since it shoots the 39 gr big brother just fine.

A guy who shoots a lot of Savages told me tonight at the range that he sent back a gun to Savage that was keyholing and they replaced the barrel and his problem went away. It's certainly worth calling them about it on Monday. But, in the meantime I was just curious of what your thoughts were?

[Hedge]

Just from what you've said about shooting other bullets without key holing, I'd say it's the BK 32's. Might be a bad batch or the fact that
some bullets just don't shoot well in a particular rifle

[Rick in Oregon]

I'd opine that it's the rifle.

The Sierra 32gr BK is THE most accurate bullet in four of my 204's, and has posted the dinkiest group ever fired with my 20 Vartarg.....in the .1's. With that kind of performance from five different rifles, it seems your rifle just does not care for this particular bullet.

The good part is......you've got lots of other choices in regard to .204" bullets.

[Fred_C_Dobbs]

Are you talking full-fledged hitting the target broadside keyholing or just somewhat oblong holes keyholing?

[sharptailhunter]

Thanks for the responses thus far. Yeah Fred, they are perfect side profiles of the bullet. And, they are way off the mark. I'm kind of at a loss as to what I should do with this rifle. It should be shooting a lot tighter groups than it is. I have tried so many bullet and powder combinations. I even bought new Nosler brass to see if that would help. The reason why I was disappointed about the Sierra 32 BKs is because I know how well they have worked in everyone else's rifles. So, when my rifle won't even shoot a great bullet without keyholes, it makes me wonder if there is something really wrong with my rifle? I'm fairly confident it's not the yahoo behind the gun... After all, I qualified expert in everything I fired in the military and I can even shoot my 30-06 with cheap factory ammo and a cheap Walmart scope better than this rifle is shooting.

[Fred_C_Dobbs]

...Yeah Fred, they are perfect side profiles of the bullet....

Dayum.

I do IT stuff for a living. When I'm running down the source of a problem, if the evidence doesn't give me enough clues, I just resort to swapping known good components for suspect ones. The problem always ALWAYS follows the bad component.

I can think of exactly five reasons why a bullet might not stabilize.

1. The bullet is too long
2. The twist is too lax
3. The MV is too low
4. The barrel -- probably the crown -- is flawed
5. The bullet(s) is (are) flawed

As for #1, you successfully are shooting longer bullets without experiencing this problem.
As for #2, the solution is the same as #1.
As for #3, your longer (heavier) bullets presumably are fired at a lower MV, yet they show no such instability.
As for #4, not every bullet you are shooting experiences the same problem, which reduces the likelihood that the crown is the cause.
As for #5, nothing you have presented reduces -- much less eliminates -- the probability that the bullets themselves are the cause.

1. Tumbling occurs only ONLY when bullets are inadequately stabilized.
2. If you are firing other, heavier, longer bullets (presumably with lower MV, hence fewer RPMs) and they are not keyholing, that would tend to indicate the problem is neither with the rate of twist not the condition of the crown.

[Joe O]

Shoot other bullets to see if they have a tendency to keyhole.I don't believe it's the bullet.Call customer Service and request a UPS pick up order to send it back.Make sure it is doing it with factory ammo,and don't mention reloads.They get guns back all the time for barrel issues.A+ customer service.

[sharptailhunter]

Fred, nice run down of possible problems. It has shot 39 and 40 grainers without any keyholing. I haven't measured the muzzle velocity yet. Perhaps that can be my next step. However, I always load using published data from the proper sources.

Joe, I have heard good things about Savage's customer support. I'll call them on Monday. The problem is, it only has done it with reloads. The only factory ammo I have shot through it was some Remington 40 grain stuff when I first bought it. No keyholing then.