6 CM & 108 ELD Velocity - Barrel Length

[Kimber7man]

I have a Tikka 6CM with a 20” Bartlein barrel. With factory 108 ELD-M I’m getting 2869 based on real world drop data out to 1300yards.

Dang - almost dead on same here. 20" Bartlein, factory 108 ELDM ammo getting 2,870 in mine...

ETA I'm getting like 2,750 with factory Berger 105 hybrid ammo. Head scratcher since it's listed around 2,950 I think.

 

[Lemhi]

Bartlein 7.5 twist @20” was 2925fps albeit with 108 Berger elite hunters.

40.2 grains of h4350
ADG brass
210m
108 Berger EH
OAL @2.80”

YMMV

 

[Mulyhuntr]

Figured creed would be faster than 243. Getting 2975 with 41.9 h4350 with 108 eldm and over 3k with h1000 from a 22" 243 tikka.

 

[wind gypsy]

Figured creed would be faster than 243. Getting 2975 with 41.9 h4350 with 108 eldm and over 3k with h1000 from a 22" 243 tikka.

Smaller case longer throat. Pretty close!

 

[FullyTorqued]

My 16” carbon six barrel is shooting factory 108 eldm’s at 2660.

@Sadler Any regrets/lessons learned from going with the 16” 6CM?
@wind gypsy Any regrets going 18” vs 16”?

 

[wind gypsy]

@Sadler Any regrets/lessons learned from going with the 16” 6CM?
@wind gypsy Any regrets going 18” vs 16”?

Nope. I’d do it again. With 6-7” cans 18” is plenty manageable.

 

[B23]

I'm having a rifle rebarreled to 6CM for my daughter and I can't decide between going 20 or 22 but most likely I'll go 22 with this one. The suppressor I use for my 6 and 6.5's is an SAS Barricade and they're just a little over six inches long so it'll still be a reasonable length.

My current 6CM has a Proof CF 9tw 20in barrel that right from the first load worked up for it has shot amazingly well but I'm not sure that is always the case. CF wrapped barrels have a certain "look" you either do or don't like but other than esthetics I don't think there is really anything beneficial about them versus an all steel barrel.

 

[FullyTorqued]

I'm having a rifle rebarreled to 6CM for my daughter and I can't decide between going 20 or 22 but most likely I'll go 22 with this one. The suppressor I use for my 6 and 6.5's is an SAS Barricade and they're just a little over six inches long so it'll still be a reasonable length.

My current 6CM has a Proof CF 9tw 20in barrel that right from the first load worked up for it has shot amazingly well but I'm not sure that is always the case. CF wrapped barrels have a certain "look" you either do or don't like but other than esthetics I don't think there is really anything beneficial about them versus an all steel barrel.

Depending how far you’re comfortable letting your daughter shoot, I wouldn’t be afraid of going for a shorter barrel with a can. Given the real world velocities above I calculated the following ballistics with the 108 ELDM at 5000’ elevation:

16” = 2660 muzzle velocity gives 2000 FPS impact at 500 yards

18” = 2764 MV gives 2000 FPS impact at 575 yrds.

 

[Shortcamo02]

I was hitting 3090 fps with factory hornady eld-m's 108gr through a 26" bartlein barrel

 

[FullyTorqued]

I was hitting 3090 fps with factory hornady eld-m's 108gr through a 26" bartlein barrel

That takes you out to 800 yards with 2000 FPS impact.
I’m trying to be honest with myself, knowing that a 16” barrel out to 500 yards is plenty for my current short and handy build, but It’s tempting to let design creep sneak in, and add a few more inches of barrel “just in case”. It takes discipline to fight that urge, especially when I could just use a 223 and 77 TMK for the shorter range stuff.

 

[Sadler]

@Sadler Any regrets/lessons learned from going with the 16” 6CM?
@wind gypsy Any regrets going 18” vs 16”?

It’s been at unknown munitions since last October so I don’t have much time behind it and haven’t been able to do load development yet. Ill be using the 109s and if I can get 2750 or so with those, I’ll be pretty dang happy. It’ll be able to take game way past my abilities

 

[bbell]

It’s been at unknown munitions since last October so I don’t have much time behind it and haven’t been able to do load development yet. Ill be using the 109s and if I can get 2750 or so with those, I’ll be pretty dang happy. It’ll be able to take game way past my abilities

I’m at 2750 with a 17” x-caliber barrel factory 108eldm ammo. I’m sure loading your own you should be able to be at 2750 pretty easy.

 

[Timjohnson11]

I’m seriously contemplating a Seekins Element in a 6 CM.. For context, I’m in Nevada and the gun would be utilized for western big game, primarily elk and mule deer. Does anyone have any thoughts or real world examples of 21” CM velocities with 108 ELDM? Is 2900 doable running a Scythe? What’s my effective range for bullet performance/velocity?

 

[FullyTorqued]

I’m seriously contemplating a Seekins Element in a 6 CM.. For context, I’m in Nevada and the gun would be utilized for western big game, primarily elk and mule deer. Does anyone have any thoughts or real world examples of 21” CM velocities with 108 ELDM? Is 2900 doable running a Scythe? What’s my effective range for bullet performance/velocity?

The 4th post in on this thread Weldor said “My Seekins Element 21" suppressed with Hornady factory ELD-X 103 gr. is 2883 from my Labradar.”

That would give you a 2000 FPS impact velocity out to 675 yards. He was using ELDX but I imagine the ELDM is close.

 

[seand]

For a 21” barrel, this isn’t rocket science. Take book velocities for a 24” barrel and reduce by 75fps.

I can’t believe how much folks sweat a few inches of barrel vs velocity.

I’m running 108s/2780 in a seekins element 6cm. Could go way higher but its for my kid, soft recoil with the can and shoots lights out.

 

[FullyTorqued]

Or you can look at rifleshooter.com for real world data to pull from. You can see that the 6mm looses a bit more than the traditional 25 FPS per inch in the shorter lengths, but like I said above, even at 16” it’s still plenty effective out to 500 yards with 2000FPS at impact.

6 Creedmoor barrel length versus muzzle velocity (31 to 17 inches)

6 Creedmoor barrel length and velocity 6 Creedmoor is rapidly rising in popularity among long range shooters. Combining an efficient case design with the wide range of excellent 6mm bullets, the 6…

rifleshooter.com

 

[khuber84]

I’m seriously contemplating a Seekins Element in a 6 CM.. For context, I’m in Nevada and the gun would be utilized for western big game, primarily elk and mule deer. Does anyone have any thoughts or real world examples of 21” CM velocities with 108 ELDM? Is 2900 doable running a Scythe? What’s my effective range for bullet performance/velocity?

Def doable. I run 105s at 2950 from an 18", 95tmk at 3080. I wish I could get some more of the 95s! I am having a new ace 237 bore 4gr 7.5tw barrel spun at 22" tho with an alpha SAAMI spec reamer and plan to run 112mb at 2950-3050 in that rig.

 

[FullyTorqued]

Nice, what powder?

 

[khuber84]

Nice, what powder?

H4350 with 105s and ts15.5 with the 95tmk

 

[CCooper]

22" C6 1:7.5t- No Can
Alpha Virgin LRP
fed GM210M primer
108 ELDM- .120 off jamb
44.0 gr N555
3052 Avg. FPS
ES of 6

This is a spicy load- about a grain under pressure signs in this barrel- as always, work up carefully.