Range Report 6mm Dasher & 110 SMK's

[earthquake]

There is some good discussion in the FB group, but I thought I'd share, as well as ask, here too for those that don't do the FB thing.

Open discussion about the 110 gr SMK bullets in your 6-Dasher.

 

[earthquake]

What BC are you guys using?
In talking with the Area419 Team guys, they said they use a 0.315 G7 in their 6-Creeds.

I did a ladder test recently at 517-yds using a 0.316 G7 (entered the known G1 in Kestrel Link and switched it to G7 to get that number) and it was gtg for that distance anyway.

Vertical dispersion for my load was <1/2".

Interestingly, when I updated my bullet library, AB says G7 for this bullet is 0.303. I am shooting a match next weekend and will see then how they do out farther.

Edit to add: My load - 30.8-gr H4895, CCI 450, Lapua, 2.400" OAL, 8-twist Hawk Hill.

 

[phxfa]

What BC are you guys using?
In talking with the Area419 Team guys, they said they use a 0.315 G7 in their 6-Creeds.

I did a ladder test recently at 517-yds using a 0.316 G7 (entered the known G1 in Kestrel Link and switched it to G7 to get that number) and it was gtg for that distance anyway.

Vertical dispersion for my load was <1/2".

Interestingly, when I updated my bullet library, AB says G7 for this bullet is 0.303. I am shooting a match next weekend and will see then how they do out farther.

Edit to add: My load - 30.8-gr H4895, CCI 450, Lapua, 2.400" OAL, 8-twist Hawk Hill.

Whats your velocity?

 

[earthquake]

2,840 fps.
DA was 2,400'
1,157' asl, 81° F

2.6-MIL's

 

[craigos]

H4895, F205M, 110SMK, seated at 2.42 OAL to fit the PVA AICS insert - 2970 fps. Now I have the ARC mag going to play with seating it out further because at 2.42 its about 100 thou jump.

 

[Jointshooters]

Looks like some on FB are having success with 110s from a 1:8 twist...

 

[earthquake]

H4895, F205M, 110SMK, seated at 2.42 OAL to fit the PVA AICS insert - 2970 fps. Now I have the ARC mag going to play with seating it out further because at 2.42 its about 100 thou jump.

What is your charge weight, and are you experiencing any pressure issues? Thanks

 

[Killswitch Engage]

you wouldnt see any difference in a bc from .300 to .320 at 500yd. you need to shoot it out beyond 800 on watermarked steel or something. i am using .315 with a 7tw at 3060fps fwiw.

 

[Carl_Ross]

This is the load I've been running in competition:

110 @ ~ .015" jam
31.7 Varget
CCI 400
Lapua brass

2866 fps (magnetospeed at three sessions) - 26" 1-7.5 Kreiger
G7 of .315

Using these inputs in my BallisticsARC program has provided accurate data out to 1100 yds consistently.

 

[Carl_Ross]

Also, I'm running a customized Primal Rights kit as the OAL of my setup was too long as it was manufactured. Shortened up the spacer on a belt sander and glued it in place.

 

[craigos]

What is your charge weight, and are you experiencing any pressure issues? Thanks

31.65 (I use a sartorius, the 0.05 just put me dab smack in the middle of my node and forces me to do a better job at trickling). I went up to 31.8 and started getting some primer cratering so backed it down. This is also with a 2.42 OAL due to the BR AICS kits, now i am running ARC I will seat that bullet out 2.52 (10 thou) and that will reduce my overall pressure (pv=nRT Ideal gas law).

 

[earthquake]

These shot great at a match this past Saturday. However, my Magnetospeed was saying 2,837 average velocity. But when I got to the range, actual drop at 1,000 said MV should be 2,880. I ran what speed the bullet was telling me on target, 2,880, and did well enough to take 4th place. I pointed them at steel and that's where they went.

The first stage was a 1,000 yard cold bore, and 7.6-mils nailed it.
I am jumping these 0.060" in an 8-twist, h4895.

 

[earthquake]

FWIW, it's a BC issue in Applied Ballistics. Instead of not believing my MagnetoSpeed and altering my MV, I should have edited the BC. A BC of 0.315 gives the proper drops with a MV of 2,840, vs. using the custom drag model and needing to tweak the MV to 2,880 to get things to line up.

 

[craigos]

These shot great at a match this past Saturday. However, my Magnetospeed was saying 2,837 average velocity. But when I got to the range, actual drop at 1,000 said MV should be 2,880. I ran what speed the bullet was telling me on target, 2,880, and did well enough to take 4th place. I pointed them at steel and that's where they went.

The first stage was a 1,000 yard cold bore, and 7.6-mils nailed it.
I am jumping these 0.060" in an 8-twist, h4895.

This is the same issue I was having - using custom curve , calc MV added 40 fps ... i should do the same

 

[Cody S]

Anyone care to add barrel length? I’m planning a 27” and planning to use varget, would that be a good powder for the 110smk in a dasher? 135 freebore

 

[earthquake]

I ran a 26" 8-twist, and had a 27" 7.5-twist recently spun up for next year. FB is 0.104" on both.
My throat eroded quite a bit with ~1k rounds down it. I was mainly using H4895 with 110's at 2,835 fps, and ran 105's with Varget at ~2,950 fps.

 

[earthquake]

reubenski I'll check in the next day or so on the amount of throat. It's a Bartlein.
32.9-gr Varget
31.somethin' of 4895