Range Report New AI AXMC .338 Lapua, Do These Velocities Sound Right?

[Monk Medic]

So it took the new rifle out today, to get my 100 and 300 yard zeros, and to gather data.
Specfications - New AI AXMC in .338, 27” barrel, Nightforce 7-35 ATACR F1 optic, Mil-C reticle, Spur mount.

My notes below, and I used my Magnetospeed chrograph to get the velocities and SD.
I’ve recorded them below.
Ran Lapua .388 300 gr Lapua Magnum ammo.
These seem low to me, makes me wonder if my Magnetospeed is wrong, or these are indeed the correct numbers?

 

[Supersubes]

I don’t think its slow, although I’ve never shot factory lapua ammo. Both my 338’s pushed 300’s at basically that velocity. Accuracy is all that matters.

 

[Monk Medic]

I don’t think it is, although I’ve never shot factory lapua ammo. Both my 338’s pushed 300’s at basically that velocity. Accuracy is all that matters.

Thanks, been reading these high 2,000 like 2,900 or so reports and wondered.
Accuracy wise it’s a tack driver, one hole groups at 100.

 

[lash]

That is typical for factory Lapua ammo. Those high 2800-2900 fps numbers are from people who are hand loading and typically with longer OALs too.

 

[Monk Medic]

That is typical for factory Lapua ammo. Those high 2800-2900 fps numbers are from people who are hand loading and typically with longer OALs too.

Excellent, exactly what I needed to know.
Appreciative you taking the out to reply.

 

[Dave62677]

i did chrono 2 boxes of lapua 300gr ammo with my axmc 27"bbl at 27.75inhg, 65F, 18% humidity, avg at 2700fps. Your numbers look right

 

[jfields]

That's right where I would expect it to be. Have fun!

 

[Monk Medic]

Thanks!

 

[Laseredge]

Getting 300’s over 2800fps out of a 27” barrel is pushing them pretty hard.
285’s make it a bit easier.

 

[Monk Medic]

Dave thanks for that confirmation.
I’m initially only shooting the Lapua factory ammo as I gather data, your info was most helpful in determining my findings normal.

Laseredge, thanks for the feed back, appreciate that. Working on the factory ammo now, I’m not set up for custom loads.

 

[Dave62677]

Just additional info I want to share which I experienced with the AXMC factory 338lm bbl

An OCW node between 90.3~90.8 with H1000 , Lapua brass, 285gr ELDm, fgm primer, Bullet seating right at land = 2800fps, ES 9, heavy bolt lift, 1/3 moa group at 109yards, two 2 shots groups

90.2gr N570 with Peterson brass, 285gr ELDm, Fgm primer, seat at the land =avg 2725fps, ES 12, easy bolt lift, .4 moa group at 109 yards, 5 shots group , 2/10 hit at 2060 yard 36” target with 17mph cross winds

 

[GIXXER2000]

When i shot Factory .300 my FPS was very close to yours. When i hand loaded 300 Hybrid i am at 2742 AVG and can push 286 ELD-M at 2815 with out issue. Your barrel with speed up just a bit after 100 rounds or so. I saw about a 15 FPS gain on mine.

 

[TripleBull]

You will probably pick up 50 fps or so as the barrel breaks in. I had to run a couple hundred rounds through my 338 before the MV peaked. Your notes show 50F so at summertime temps you might see a little bump in the MV from the heat also.