Here are the results from my experience with the Lapua test center a few years ago. Gun is an 1807 with the factory barrel that was taprered to meet hunter class rules. Even though batch 9 was slightly better at 50meters, it fell apart at 100meters. These are 20 shot strings, much harder to get a sub moa load than with just 5 rounds. The batch 5 is about 22mm center to center at 100meters, so about 0.8 moa for 20 rounds.

I had some SK+ tested as well as a baseline since that is what I have been using up to that point. I thought it was shooting good, and I won AAA at the nationals with SK+ in 2018. But it shot at 21.5mm at 50m at a whopping 46mm at 100m.

Another weird thing that happened at this test and at another test I was there in 2022 for, occasionally a bullet would in 1 location at 50m but at the opposite at 100m. Like low or left at 50m, but high or right at 100m. This was pretty rare but happened a few (3-5) times each test. The rest would hit low at 50m and even lower at 100m (or high and even higher). But occasionally they would do the opposite, that was very ineresting and very surprising.

For anyone that doesn't know, the Lapua Mesa test center is a concrete tunnel 100m long with laser targets measuring the dispersion of the same bullet at 50m and 100m without anything impacting the trajectory of the bullet. For a $50 fee at the time, it was good experience if you don't buy any ammo, and they waive the test fee if you buy 2 or more lots of ammo.

thauglor wrote: ↑Sun Jul 03, 2022 10:55 am Another weird thing that happened at this test and at another test I was there in 2022 for, occasionally a bullet would in 1 location at 50m but at the opposite at 100m. Like low or left at 50m, but high or right at 100m. This was pretty rare but happened a few (3-5) times each test. The rest would hit low at 50m and even lower at 100m (or high and even higher). But occasionally they would do the opposite, that was very ineresting and very surprising.

I've heard about (and seen in videos) a corkscrew effect that some bullets/pellets can have. Here's a not-great video I found which shows air rifle pellets corkscrewing into the target. That may have been why some of your bullets hit low-left earlier and high-right later.

https://www.youtube.com/watch?v=NB7Wu88JJso

Thanks for posting your findings!

That explains unexplained misses during matches.

Thanks for the video Allen, thats about as good of a video of the bullets in flight as we will get without going highend and spending $10000 on equpiment. I figured it was corkscrewing, that is about the only thing that can explain the results on the target I was seeing. The good shooting ammo did not see such results in 20 rounds that were tested. If I had the money it would be interesting to send a 1000 rounds of the same good shooting lot in the tunnel to see the results

That may also explain why, on some rifles, hand loading a single round into the chamber can be more precise than from a magazine.

Sporty wrote: ↑Mon Jul 04, 2022 3:06 pm That may also explain why, on some rifles, hand loading a single round into the chamber can be more precise than from a magazine.

How so? Are you trying to suggest the corkscrew effect came from bullet damage? Based on what evidence? All the ammo was single fed jnto the chamber on my 1807, even the ones that did corkscrew

I didn't mean to suggest your rifle. My comment was about the pellet video. Since the author of the corkscrewing pellet mentioned shaving some lead off the pellet it made me recall what was suggested to me that a round chambered from a magazine might mark the bullet on its way to the chamber.

Sporty wrote: ↑Mon Jul 04, 2022 4:59 pm I didn't mean to suggest your rifle. My comment was about the pellet video. Since the author of the corkscrewing pellet mentioned shaving some lead off the pellet it made me recall what was suggested to me that a round chambered from a magazine might mark the bullet on its way to the chamber.

Thanks, with the new YouTube look I didn't see the posts made by the youtuber, it's usually said in the video and not in the text box. I'm still convinced that had more to do with the bullet impacting the moderator and getting upset then shaving of the lead but I have no proof either way

High right 50m
Low left 100m
Somebody found thier "cone of wobble".