Bullet myth I just heard.... or is it fact?

[1911man]

So I was talking to a buddy of mine who also shoots grendel about taking a box of varying handloads to the range for testing and he tells me what sounds like a Grendel myth. He says that after shooting a load with one particular bullet it takes and a break in shot or two to shoot another bullet. So for example if I have been shooting 20 rounds of 123 AMAX and I switch to a load with 107 SMKs my first shot with the SMKs will be a flyer because of the bullet switch. He said particularly he has heard the Nosler 120 BT is sensitive to this. Has anyone ever heard of or can confirm this? I have heard something similar in the past about shooting rounds with different powders. That fouling the bore with the same powder for your groups will give you better groups than if you switch back and forth between groupings with loads of different powders. I have always wrote this off as I can see no reason it would be true.

[Fredman]

I always clean my barrel after shooting Noslers and before shooting something else. As far as powders, the only thing I've experienced is most barrels shoot their best a little dirty.

[SG4247]

I have heard this for several years.

Cant say that I have ever been able to validate it in thousands of rounds of testing handloads.

[1911man]

I always clean my barrel after shooting Noslers and before shooting something else. As far as powders, the only thing I've experienced is most barrels shoot their best a little dirty.

Fredman, what is your reason for doing this? is there any science to back this up? Do the Noslers leave behind more copper or something?

[bwaites]

Many of us have experienced Nosler Bullets causing the first few shots with other Bullets to not go to point of aim. It was widely discussed on the old board, and Bill Alexander noted that he had seen similar things with Noslers. Noslers have always been among the most accurate Bullets in my Grendels, (in fact the smallest groups I have shot have all been Noslers).

When testing, I typically will simply shoot the Noslers last. However, I always make sure I shoot a couple rounds of the new load anytime before I shoot for groups anytime I change loads or bullets. I do use those first few rounds for chronic testing though.

This isn't just a a Grendel issue, either, I've seen it discussed on other boards as well.

[1911man]

Many of us have experienced Nosler Bullets causing the first few shots with other Bullets to not go to point of aim. It was widely discussed on the old board, and Bill Alexander noted that he had seen similar things with Noslers. Noslers have always been among the most accurate Bullets in my Grendels, (in fact the smallest groups I have shot have all been Noslers).

When testing, I typically will simply shoot the Noslers last. However, I always make sure I shoot a couple rounds of the new load anytime before I shoot for groups anytime I change loads or bullets. I do use those first few rounds for chronic testing though.

This isn't just a a Grendel issue, either, I've seen it discussed on other boards as well.

Interesting stuff, I had never heard of this before. It is certainly going to make my day of testing more of a hassle. Have you ever heard an explanation as to what people think causes this?

[JASmith]

Point of impact when changing bullets or powders has been a metter of faith for so long that I cannot remember when I first heard about it.

That said, actually observing the change depends hugely on shooter skills and the intrinsic accuracy of the rifle.

The difficulty of observing leads people to forget that the phenomena does exist.

The Grendel, with a combination of excellent accuracy and mild recoil coupled with modern opitcal sights, allows more shooters to rediscover some of the old knowledge.

[bwaites]

Interesting stuff, I had never heard of this before. It is certainly going to make my day of testing more of a hassle. Have you ever heard an explanation as to what people think causes this?

The most common explanation is that they copper used by Nosler is a different alloy and it takes a few bullets for any change to settle in. It could also be that they are using a powder that has a copper cleaner or a powder that allows more alloy to be laid down than other powders, but all of that is just an educated guess at this point.

[kmon]

Have observed this with other calibers and bullets, while others have seen no change. Had a TC ICON in 308 that could shoot 1/2 to 5/8 groups with at 100 with boring regularity. Had a few factory loads Remington with Swift Siroccos, Nosler accubonds and Federal match kings. Before I sold the rifle I shot the remainder of that ammo up with 6 three shot groups with one shot of each load at 100 yards, those groups averaged 5/8 inch. the largest being 3/4 and the smallest just under a half. In a 7mm-08 doing something similar but just switching groups emptying brass for reloading that shot to different points of impact I shot 1 group of each ammo and the groups were larger than if I stuck with one ammo through several strings with the same ammo.

From what I have done with those rifles and a couple more I think it has to do more with a particular barrel than the bullet material. Some guns it seems to make a difference while others it seems to make no difference with different bullets.

[joker31]

the cfe223 is very much a comfirmation of it, I get 2-3 moa from a dirty xbr used bore, clean it and use cfe after 5-10 rounds get 1moa