Why does my rifle throw the first round when I switch ammo/bullets?

[JaoeyP]

I have a Howa in 243 that consistently throws the first round when I switch from my bullet to another. For example, I was doing some load development yesterday with 95gr Berger Classic Hunters, switched back to my tried and true load with 95gr Sierra Match Kings, first round was 2" outside of the next 4, which grouped right under .6 MOA. This has been a consistent phenomenon throughout my experiences with the rifle. It ALWAYS throws the first round if I change bullets, then settles right in. Difference in copper fowling between the rounds?

Just curious on this. It doesn't bother me as I can plan and account for it.

 

[KevinThomas]

It's not at all unusual for major changes in POI when switching ammo like this, due to different powders being used. This seems to be especially true when bouncing between single-based extruded powders and double-based powders. The fouling residue left by each just seems antagonistic to others, and it often takes several rounds for the fouling to change back to the original POI.

 

[Nobody]

What about same powder, same charge, same wt bullet, but just a different brand. That's what the op sounds like he asking to me. Clarify?

 

[JaoeyP]

What about same powder, same charge, same wt bullet, but just a different brand. That's what the op sounds like he asking to me. Clarify?

Yes. Same everything except bullets and the first shot will be 1.5-2.5" outside of the next 4/5.

 

[okie]

naked?

 

[JaoeyP]

naked?

Not sure what naked means in this scenario?

 

[okie]

Not sure what naked means in this scenario?

figure it would take more than one to settle down anyway....moly, danzac,owl snot, etc.
--naked is plain ole j4 copper jacket

 

[JaoeyP]

figure it would take more than one to settle down anyway....moly, danzac,owl snot, etc.
--naked is plain ole j4 copper jacket

Ah yes, naked.

 

[joshb]

WellIf I was fed Bergers and then my owner fed me Sierras, I'd spit, too!

 

[jpx2rk]

Barrel harmonics change because of the different bullet profile???

 

[Milo 2.0]

I cannot fathom switching bullets w/o stripping my barrel clean, as KT above said above, fouling, I go farther and say diff bullets shed jacket in different patterns in a barrel too, and I've never gotten more than 10 accurate shots after switching, to me it degrades fast.

 

[IdahoSharpshooter]

differing bearing surface length, perhaps...?

 

[msinc]

WellIf I was fed Bergers and then my owner fed me Sierras, I'd spit, too!

I know this is funny and to some degree at least written in jest, but......there really is something to it. I mean, back in the early 90's when I first got my hands on my first really accurate custom rifle it shot most bullets really well, but especially the Sierras'. Any "match" bullet of any brand would produce consistent, fantastic groups.
These days, as in the last 6 or 7, I cannot get anything to shoot but Berger bullets. With the exception of Nosler Partitions, which I could never get to shoot in anything and still cant...what has happened to the rest of the bullet making world???? Is their bullet making machines worn out?? QC gone out on permanent lunch, what?????
I hate to talk down on anything unless I can really state specifically what the problem is, but in the last year I have worked on three different rifles that appeared to have an accuracy issue. Only to confirm with Berger bullets that there was nothing at all wrong with the rifles and nothing more than a "bullet" issue. Maybe it was something else...but when you go from 1 1/2" groups or worse to all bullets touching in a group and nothing changed but the bullets.......?????????

 

[KevinThomas]

Changing bullets is changing bullets, even if they're the same weight. Differences in ogive, bearing surface, and even differences in what should be very similar gilding metals could all contribute to the POI shift. Basic rule of shooting, never assume, never take anything for granted. Sure way to get bitten in the ass nine times outta ten.

 

[joshb]

I was speaking in jest. Humor is my fallback position when I confront the unexplainable phenomenon. It would be easy to conclude that it's caused by "cheaper bullets" except that it's just the first shot. I have read SOOOO many posts about the "unexplained flier". People have thier theories and one, or a combination of some, may be true. I have no empirical data for it, tho. My head spins trying to figure it out and left with no answer, I proposed a wacky theory.

 

[JaoeyP]

I know this is funny and to some degree at least written in jest, but......there really is something to it. I mean, back in the early 90's when I first got my hands on my first really accurate custom rifle it shot most bullets really well, but especially the Sierras'. Any "match" bullet of any brand would produce consistent, fantastic groups.
These days, as in the last 6 or 7, I cannot get anything to shoot but Berger bullets. With the exception of Nosler Partitions, which I could never get to shoot in anything and still cant...what has happened to the rest of the bullet making world???? Is their bullet making machines worn out?? QC gone out on permanent lunch, what?????
I hate to talk down on anything unless I can really state specifically what the problem is, but in the last year I have worked on three different rifles that appeared to have an accuracy issue. Only to confirm with Berger bullets that there was nothing at all wrong with the rifles and nothing more than a "bullet" issue. Maybe it was something else...but when you go from 1 1/2" groups or worse to all bullets touching in a group and nothing changed but the bullets.......?????????

So far I haven't gotten Bergers to shoot well in this gun. Sierra 95gr SMKs have performed best. I should clarify too; this is a factory barreled action and I am not an advanced handloader or bench rest shooter. I like tinkering with loads for this rifle for the sake of it. The issue I'm having here is repeatable and predictable so it doesn't really cause me grief.

I have to wonder if Bergers are working so well for you for the same reason a fisherman catches all his fish on his favorite lure- because you use them all the time. Maybe you've gotten good at tuning loads with Bergers, but given the same time/opportunity with another brand perhaps you'd get them to perform as well. I've always had good luck with Hornady and Sierra bullets and have yet to get a Berger to consistently shoot under a minute. I also haven't spent nearly as much time loading/shooting Bergers.

 

[rogn]

msinc; Ive found more of the opposite to be true, that there are more accurate bullets available than ever before. And some of the old clunkers are better than they once were. i think what we have to consider is that there are so bloody many variables associated with shooting and loading ammo that its possible to hit the negative side of the variables just as you might hit the positive side. Sort of tolerance stacking. As the old expression goes, " wind can blow shots into a group as well as out of one"
At htis point for most hunting guns when I work on a load its usually only working up with one powder, primer and bullet to achieve really excellent accuracy. For hunting including Varmits, any on the small side of an inch is fine with me. Some on the other hand are astonishing.

 

[yukonal]

I was speaking in jest. Humor is my fallback position when I confront the unexplainable phenomenon. It would be easy to conclude that it's caused by "cheaper bullets" except that it's just the first shot. I have read SOOOO many posts about the "unexplained flier". People have thier theories and one, or a combination of some, may be true. I have no empirical data for it, tho. My head spins trying to figure it out and left with no answer, I proposed a wacky theory.

We need a little more humor in this world.