Do I have a slow barrel?

SuperSneakySniper

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Minuteman
Feb 16, 2017
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Sup fellas.

I've got a 6.5CM barrel (made from a Bartlein blank I believe). It's stated at 24". From action face to muzzle it's a little under 23" (I'm guessing that's normal?). From what I can find online, it seems it's shooting Factory Hornady ELD-M 140gr a bit slow. But I could be wrong.
I'm only getting an FPS of about 2677. Is that normal? I have no other 6.5 rifle to compare that figure to.

I've got about 100 rounds through it. I initially ran a boresnake through it a couple times just to clear it up before shooting. After that I fired about 20 rounds to foul it out a little and get an initial zero. Then I chrono'd it. Temperature outside was a pleasant 65 F.

It's no huge deal either way, Strelok tells me I'm supersonic well past a kilometer which is far enough in my book. Just figured I'd ask.
Was plinking steel at 600 monday. Had a blast!
 
They advertise those at 2710 but it varies from lot to lot. I wouldn't consider your barrel slow at 23 FPS under what they say. Also missing from the equation is your barrel twist. Being supersonic past a Kilometer is really kind of misleading, your bullet will be effected by the pressure wave in the transonic region which is around 1.2 Mach. With that bullet and velocity look for your accuracy to drop off closer to 1000-1100 yards.
 
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It will probably continue to speed up for the next 100 rounds or so.

Ah okay. I'll continue to chrono it as I take it out and see what happens.

They advertise those at 2710 but it varies from lot to lot. I wouldn't consider your barrel slow at 23 FPS under what they say. Also missing from the equation is your barrel twist. Being supersonic past a Kilometer is really kind of misleading, your bullet will be effected by the pressure wave in the transonic region which is around 1.2 Mach. With that bullet and velocity look for your accuracy to drop off closer to 1000-1100 yards.

Thanks for the info, barrel twist is the ol' standard 1/8. I was always wondering where the "transonic region" started affecting the bullet. Thanks for the figure.
Well then hopefully she speeds up a little bit after a few more boxes and I'll start to see some of that 2700ish action. Thanks!
 
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No problem. The transonic region is generally defined as .8 to 1.2 mach. I am shooting some hand rolled Hornady 140gr ELD-Ms out of a RPR 24" barrel at exactly 2700 FPS and Applied ballistics says im at 1.21 mach at 1120 yards. Of course just a change in the weather can effect that velocity and yardage number a bit. I know some guys get decent shots out to 1200 yards with about the same setup and ammo, but i wouldn't be confident in taking them out to 1400 and if i was missing at 1200 the velocity would be my main suspect. I have shot these rounds out to 1047 yards with great results but I am trying to get my velocity up in the 2800 FPS range to keep out of that transonic range farther out, that's if my barrel will shoot it well at that velocity of course.
 
I have a 26” bartlein and avg 2700fps with the same ammo. Your barrel isn’t slow. The ammo is. Remember that velocity changes with the weather. It is a variable. Shoot in different temps and keep notes that way you can allow for it accurately.
 
Same ammo is doing 2650-2660 in my 26" Bartlein with less than 100 through it right now. I'm sure it will speed up but it sounds about right based on the lot I have been using.